Endangered Species Act Section 7 Consultation Biological Opinion

INTRODUCTION
Section 7(a)(2) of the Endangered Species Act (ESA) (16 U.S.C. § 1531 et seq.) requires that
each federal agency shall ensure that any action authorized, funded, or carried out by such agency
is not likely to jeopardize the continued existence of any endangered or threatened species or
result in the destruction or adverse modification of any critical habitat of such species. When the
action of a federal agency may affect a protected species, that agency is required to consult with
either the National Marine Fisheries Service (NOAA Fisheries) or the U.S. Fish and Wildlife
Service (USFWS), depending upon the protected species that may be affected. Formal
consultations on most listed marine species are conducted between the action agency and NOAA
Fisheries. Consultations are concluded after NOAA Fisheries’ issuance of a biological opinion
(opinion) that identifies whether a proposed action is likely to jeopardize the continued existence
of a listed species, or destroy or adversely modify critical habitat. If jeopardy or destruction or
adverse modification is found to be likely, the opinion must identify the reasonable and prudent
alternatives (RPAs) to the action, if any, that would avoid jeopardizing any listed species and
avoid destruction or adverse modification of designated critical habitat. The opinion also
includes an incidental take statement (ITS) which specifies the amount or extent of incidental
taking that may result from the proposed action. Non-discretionary reasonable and prudent
measures (RPMs) to minimize the impact of the incidental taking are included, and conservation
recommendations are made. Notably, there are no reasonable and prudent measures associated
with critical habitat, only reasonable and prudent alternatives that must avoid destruction or
adverse modification.
The present consultation considers the continued authorization of the Atlantic pelagic longline
fishery as managed under the Fishery Management Plan for Atlantic Tunas, Swordfish, and
Sharks (HMS FMP). NOAA Fisheries has dual responsibilities as both the action agency under
the Magnuson-Stevenson Fishery Conservation and Management Act (MSA) (16 U.S.C. 1801et
seq.) and the consulting agency under the ESA. For the purposes of this consultation, the Highly
Migratory Species Management Division (HMS Division) of NOAA Fisheries’ Office of
Sustainable Fisheries (OSF) is considered the action agency, and NOAA Fisheries’ Southeast
Regional Office (SERO) is the consulting agency. This opinion has been prepared by the SERO
Protected Resources Division (SERO-PRD). This document constitutes NOAA Fisheries’
opinion on the effects of the U.S. Atlantic pelagic longline fishery (herein referred to as the HMS
pelagic longline fishery), on threatened and endangered species and critical habitat, in accordance
with section 7 of the ESA. Specifically, this opinion analyzes the effects of proposed regulatory
modifications to the HMS FMP that address the impacts of the HMS pelagic longline fishery on
endangered green (Chelonia mydas), hawksbill (Eretmochelys imbricata), Kemp’s ridley
(Lepidochelys kempii), and leatherback sea turtles (Dermochelys coriacea) and on threatened
loggerhead (Caretta caretta), and olive ridley sea turtles (Lepidochelys olivacea). This opinion
also evaluates the likelihood of effects on other marine listed species.
This opinion is based on the following information sources:

ii

•
•
•

•

•
•
•
•
•
•
•

The February 11, 2004, proposed rule to modify regulatory requirements for the HMS
pelagic longline fishery to reduce sea turtle bycatch and mortality (69 FR 6621);
The Draft Supplemental Environmental Impact Statement (DSEIS) associated with the
February 11, 2004, proposed rule;
The April 20, 2004, memorandum from OSF to SERO regarding revised alternatives
under consideration for the final rule to modify regulatory requirements for the HMS
pelagic longline fishery to reduce sea turtle bycatch and mortality.
The June 20, 2003, proposed rule to implement north and south Atlantic swordfish
recommendations from the 2002 International Commission for the Conservation of
Atlantic Tunas (ICCAT) meeting (68 FR 36967);
The DSEIS associated with the June 20, 2003, proposed rule;
Sea turtle recovery plans;
Past and current research and population modeling efforts;
Observer and logbook data on fishery effort and protected species interactions in the
HMS pelagic longline fishery;
The results of recent experiments to evaluate methods to reduce sea turtle bycatch and
mortality in the HMS pelagic longline fishery;
Other relevant scientific data and reports, consultation with HMS Division staff; and
Previous opinions for this and other relevant fisheries.

A complete administrative record of this consultation is maintained at SERO.

iii

1.0

CONSULTATION HISTORY

1.1

Previous Consultations

Over the past two decades, NOAA Fisheries has conducted numerous formal and informal ESA
section 7 consultations on Atlantic HMS fisheries managed under the HMS FMP and
Amendment 1 to the Billfish Fishery Management Plan (Billfish FMP). Earlier consultations are
summarized in the June 30, 2000, and June 14, 2001, consultations. The June 30, 2000, and June
14, 2001 consultations and subsequent consultations are discussed below. Collectively, these
consultations have comprehensively covered all components of the Atlantic HMS fisheries: the
fisheries for tuna, swordfish, sharks, and billfish (recreational only) in the western Atlantic,
Caribbean, and Gulf of Mexico, including the pelagic driftnet, drift gillnet, pelagic longline,
bottom longline, purse seine, and hand gear (hook and line, handline, and harpoon) fisheries.
The June 30, 2000, opinion on the continued authorization of HMS fisheries considered a
December 15, 1999, proposed rule (64 FR 69982) to implement various time-area closures in the
HMS pelagic longline fishery. The time-area closures were intended to conserve billfish and
undersized swordfish. That opinion concluded that, even with the proposed closures, the HMS
pelagic longline fishery was likely to jeopardize the continued existence of loggerhead and
leatherback sea turtles. To avoid this jeopardy, the opinion offered two possible RPAs.
Regulations implementing the selected RPA closed the Northeast Distant (NED) statistical
reporting area to pelagic longline fishing and required HMS pelagic longline vessels to carry
dipnets and line-cutters to minimize entanglement and post-release mortality of sea turtle
bycatch.
The final rule implementing the proposed time-area closures was published on August 1, 2000,
and became effective September 1, 2000 (65 FR 47214). In that final rule, the proposed closure
of the western Gulf of Mexico to conserve billfish was replaced with a Gulf-wide prohibition on
the use of live bait with pelagic longline gear. Also, a year-round closure of the DeSoto Canyon
area in the northeastern Gulf of Mexico was added to further reduce dead discards of small
swordfish. Lastly, the final rule also modified the time-area closures proposed for the South
Atlantic region, and included a year-round closure of the area south of 31/N. latitude (the “East
Florida Coast” closure area) and a February 1 through April 30 closure of the area between 31/N
- 34/ N latitude (i.e., the “Charleston Bump” closure area).
NOAA Fisheries issued emergency regulations on October 13, 2000, that closed a 55,970 square
nautical mile L-shaped portion of the NED area to pelagic longline fishing from October 10,
2000, through April 9, 2001 (65 FR 60889). This closure, as required under the June 30, 2000,
opinion’s RPA, was intended to reduce the incidental capture of loggerhead and leatherback sea
turtles. The emergency regulations also required the use of dipnets and line-cutters to remove
entangling fishing gear and reduce post-release mortality of sea turtles captured in the HMS
pelagic longline fishery. To prevent a lapse in sea turtle post-release mortality reduction
measures, NOAA Fisheries published an interim final rule on March 30, 2001 (66 FR 17370),
1-1

which continued the requirement to possess and use dipnets and line-cutters for all vessels in the
HMS pelagic longline fishery.
NOAA Fisheries conducted a series of public scoping hearings in July and August 2000 to
present the findings of the June 30, 2000, opinion and to gather information and insights from
affected constituents. During that process, NOAA Fisheries concluded that further analyses of
observer data and additional population modeling of loggerhead sea turtles were needed to
determine more precisely the impact of the HMS pelagic longline fishery on sea turtles. For that
reason, NOAA Fisheries reinitiated consultation on the HMS fisheries on September 7, 2000.
The reinitiated consultation on HMS fisheries was concluded with the issuance of a June 14,
2001, opinion. The opinion represented a comprehensive examination of the effects of all of the
fisheries covered under the HMS FMP and the Billfish FMP on sea turtles in the western Atlantic
Ocean. The opinion incorporated findings from a January 2001, technical gear workshop in
Silver Spring, Maryland, that was attended by scientists, fishermen, environmentalists, and other
interested parties. Additionally, the opinion incorporated findings of a February 2001 document:
Stock Assessments of Loggerhead and Leatherback Sea Turtles and an Assessment of the Impact
of the Pelagic Longline Fishery on the Loggerhead and Leatherback Sea Turtles of the Western
North Atlantic prepared by NOAA Fisheries’ Southeast Fisheries Science Center (SEFSC). The
opinion concluded that the continued prosecution of the HMS pelagic longline fishery was likely
to jeopardize the continued existence of loggerhead and leatherback sea turtles. All other fishery
components, including the Atlantic bottom longline and gillnet fisheries for sharks, were found
not to jeopardize the continued existence of any ESA-listed species.
The June 14, 2001, opinion specified an RPA for the pelagic longline fishery that would avoid
the likelihood of jeopardizing the continued existence of loggerhead and leatherback sea turtles.
The RPA included the following elements:
•
•
•
•
•

Closure of the NED area to HMS pelagic longline fishing, effective July 15, 2001;
A requirement that gangions be placed no closer than twice the average gangion length
from the suspending floatlines, effective August 1, 2001;
A requirement that gangion lengths be 110 percent of the length of the floatline in sets of
100 meters or less in depth, effective August 1, 2001;
A requirement for the use of corrodible hooks effective August 1, 2001; and
A requirement for additional gear modification or fishing practices prior to reopening the
NED based on a new cooperative research program.

The opinion included a term and condition as part of the ITS that required action by NOAA
Fisheries no later than September 15, 2001, to reduce post - release mortality of turtles caught on
longline gear. The term and condition required all commercial and recreational HMS-permitted
vessels to post inside the wheelhouse guidelines for the safe handling and release of sea turtles
following longline interactions.

1-2

On July 13, 2001, NOAA Fisheries published an emergency rule to implement several of the
opinion requirements (66 FR 36711). Regulations implemented by this emergency rule included
a closure of the NED Area to HMS pelagic longline fishing, restrictions regarding gear
deployment, and a requirement to post the safe handling procedures inside the wheelhouse.
Subsequently, an August 31, 2001, memorandum from NOAA Fisheries’ Office of Protected
Resources modified the term and condition to post the safe handling procedures inside the
wheelhouse so that it applied only to bottom and pelagic longline vessels. Therefore, on
September 24, 2001, NOAA Fisheries published an amendment to the emergency rule (66
FR48812) to incorporate this change. These requirements, effective through January 9, 2002,
were extended to July 8, 2002 (66 FR 64378, December 13, 2001). On January 14, 2002, NOAA
Fisheries published an amendment to the emergency rule extension clarifying the effective dates
(67 FR 1688).
On July 9, 2002, NOAA Fisheries published the final rule (67 FR 45393) implementing all the
measures identified in the RPA to reduce the incidental catch and post-release mortality of sea
turtles and other protected species in HMS fisheries. The rule implemented the closure of the
NED statistical reporting area, required the length of any gangion to be 10 percent longer than the
length of any floatline if the total length of any gangion plus the total length of any floatline was
less than 100 meters, prohibited vessels from having hooks on board other than corrodible, nonstainless steel hooks, and required all HMS bottom and pelagic longline vessels to post sea turtle
handling and release guidelines in the wheelhouse. The final rule additionally established
regulations for the HMS shark gillnet fishery that required: both the observer and vessel operator
to look for whales; the vessel operator to contact NOAA Fisheries if a listed whale was taken;
and shark gillnet fishermen to conduct net checks every 0.5 to 2 hours to look for and remove any
sea turtles or marine mammals from their gear. NOAA Fisheries did not implement the gangion
placement requirement because it was found to result in an unchanged number of interactions
with loggerhead sea turtles and an apparent increase in interactions with leatherback sea turtles.
On August 1, 2003, NOAA Fisheries published a proposed rule for Draft Amendment 1 to the
HMS FMP. Amendment 1 dealt exclusively with measures affecting the management of sharks
and the directed shark fishery components (i.e., bottom longline, Southeast shark drift gillnet,
and recreational shark fisheries) of the HMS FMP. NOAA Fisheries determined there was a
need for a new formal consultation on the effects of the directed shark fisheries on listed species
because of new information obtained subsequent to the June 14, 2001, opinion, as well as the
recent listing of smalltooth sawfish (Pristis pectinata). The proposed rule and new information
was limited to directed shark fisheries and did not affect pelagic longline fishing effort or fishing
patterns previously analyzed in the June 2001 opinion, therefore, the scope of the reinitiated
consultation was focused on the directed shark fisheries.
On October 29, 2003, the Southeast Regional Office completed its opinion on the continued
operation of Atlantic shark fisheries under the HMS FMP and Amendment 1. The opinion
concluded that the continued prosecution of the Atlantic shark fisheries was not likely to
jeopardize the continued existence, or destroy or adversely modify critical habitat, of any ESA1-3

listed species. An ITS was included that specified the extent of anticipated take of sea turtles and
smalltooth sawfish and the reasonable and prudent measures necessary to minimize the impacts
of the take. For the directed shark fisheries, the October 29, 2003, opinion superceded the June
14, 2001, opinion.
The RPA of the June 14, 2001, opinion required NOAA Fisheries to initiate and conduct a
cooperative research program which would develop, modify, and test gear technologies and
fishing strategies to “(1) reduce the likelihood of interactions between fishing gear and sea turtles
and (2) dramatically reduce immediate and delayed mortality rates of sea turtles captured in the
fisheries.” The RPA went on to require;
Upon completion of the aforementioned research and its final analysis, NMFS Highly
Migratory Species Division must promptly conduct a rulemaking to require the adoption
of complementary bycatch reduction measures that, in concert with the bycatch reduction
measures required by this opinion and the June 30, 2000, opinion, have been shown to
achieve overall sea turtle mortality reductions of at least 55 percent. This rulemaking
must be completed before pelagic longline vessels are allowed to fish within the NED
area, other than as participants in permitted scientific research.
1.2

Present Consultation

Over the course of 2001, 2002, and 2003, the SEFSC undertook a series of research activities in
coordination and collaboration with the HMS pelagic longline fishery, academic partners, and
other NOAA Fisheries researchers to complete the above-prescribed research program. Three
seasons of field experiments were conducted aboard commercial longline vessels working in the
NED under an ESA Section 10(a)(1)(A) scientific research permit. These studies, collectively
known as the NED experiment, evaluated various fishing techniques in regard to their
effectiveness at reducing sea turtle bycatch. The studies additionally evaluated safe-handling
techniques to reduce post-release mortality for sea turtles. On March 3, 2004, the SEFSC
submitted a final report to NOAA Fisheries’ Office of Protected Resources (OPR) per section 10
permitting reporting requirements, summarizing the results of the 3-year NED experiment. The
report (discussed in detail in section 4) was made available on the SEFSC’s Pascagoula
Laboratory website (http://www.mslabs.noaa.gov/mslabs/docs/pubs.html).
On September 15, 2003, the HMS Division sent a memorandum to the OPR regarding a
proposed rule that would implement modifications to the U.S. quota for swordfish. This
proposed rule responded to recommendations put forth by ICCAT at its 2002 meeting. The HMS
Division sought concurrence with their conclusion that the proposed rule would not be expected
to alter fishing practices or fishing effort any way that would alter the conclusions of the June 14,
2001, opinion. The memorandum and its supporting documents were subsequently forwarded to
SERO-PRD for review.

1-4

While SERO-PRD’s consultation was underway on this proposed rule, on November 17, 2003,
the SEFSC notified HMS Division and SERO-PRD that the total takes specified in the June 14,
2001, opinion’s ITS had been exceeded in 2002 for loggerheads and in 2001 and in 2002 for
leatherbacks. The SEFSC issued a final report on the estimated bycatch levels in the longline
fishery on December 12, 2003 (Garrison 2003a). Staff from SERO-PRD and the HMS Division
began investigating potential causes of the excess take, effectively initiating consultation in
November 2003.
Based on this new information, NOAA Fisheries determined that a more comprehensive
management strategy might be needed for the HMS pelagic longline fishery. Further
consultation on the proposed rule to implement the U.S. quota for swordfish was postponed
pending consideration of additional management actions. NOAA Fisheries announced a Notice
of Intent (NOI) (68 FR 66783, November 28, 2003) to prepare an SEIS to assess the potential
effects on the human and biological environment from such a comprehensive management
strategy.
On January 12-13, 2004, NOAA Fisheries hosted a workshop with industry representatives and
other interested constituents to present the preliminary results of the NED experiment. In
addition, NOAA Fisheries provided the workshop participants with an overview of the NOI, the
time-line for rulemaking, and the associated ESA section 7 consultation process to implement sea
turtle conservation measures.
Because of the expansion of proposed actions, on January 29, 2004, OSF sent a memorandum to
SERO-PRD requesting formal acknowledgment that the ongoing consultations between HMS
Division and SERO-PRD represented a reinitiation of consultation on the HMS pelagic longline
fishery, pursuant to ESA Section 7. That memorandum noted that the application of the results
of the NED experiment would allow the formulation of a new fishery management regulatory
regime for the HMS pelagic longline fishery. This new management strategy would meet the
June 14, 2001, opinion’s requirement for the fishery to sustain a multi-year reduction in take and
mortality of loggerhead and leatherback sea turtles, thereby avoiding jeopardy for those species.
The memorandum also stated that a final rule to implement this new management strategy was
expected to go into effect in June 2004.
On February 3, 2004, SERO concurred with the need to reinitiate Section 7 consultation, as the
proposed rulemaking was expected to change significantly the extent and the manner in which
the HMS pelagic longline fishery interacts with sea turtles. The SERO-PRD offered to provide
advice and assistance to the HMS Division during the development of their sea turtle
conservation rulemaking.
On February 11, 2004, NOAA Fisheries published the subject proposed rule and announced the
availability of the DSEIS (69 FR 6621), with a comment period extending through March 15,
2003. Through the proposed measures, NOAA Fisheries sought to reopen the NED closed area
and implement the gear modification results from the NED experiment throughout the fishery,
1-5

including certain hook and bait measures proven to be effective at reducing sea turtle interactions
and bycatch mortality. The intent of the proposed rule was to reduce bycatch and bycatch
mortality of sea turtles caught incidentally in the HMS pelagic longline fishery.
On April 20, 2004, OSF informed SERO-PRD that they were considering revising the actions in
the final rule from those described in the proposed rule. The potential revisions were based on
public comment received during the comment period, as well as information regarding sea turtle
mortalities derived from refined post-hooking mortality estimates, changes in the environmental
baseline of the June 14, 2001, opinion for Atlantic sea turtles including new turtle excluder
device requirements in the shrimp fishery, and a re-examination of data pertaining to reductions
in bycatch and bycatch mortality associated with various hook and bait combinations. The OSF
requested that the SERO-PRD opinion be prepared based on the changes to the details of the
hook and bait requirements being considered for the final rule. The OSF also reiterated its
request that the consultation consider the proposed rule implementing the North and South
Atlantic swordfish quotas. It was further requested that the consultation consider exempted
fishing permits (EFPs) and scientific research permits (SRPs) issued under the HMS FMP.
Lastly, OSF requested that the consultation consider removal of the current reporting requirement
for operators of HMS pelagic longline vessels. Operators are required to call NOAA Fisheries by
telephone within 48 hours of returning to port to report any sea turtles that were dead when
captured, or that died during capture. This request was based on the Office of Management and
Budget’s directive for NOAA Fisheries to review and eliminate duplicative reporting
requirements. NOAA Fisheries already collects the above information thorough the observer and
logbook programs, and no reports had been received by telephone. Considering this requirement
adds no monitoring value beyond observer and logbook program requirements, the SERO-PRD
will no longer include this requirement as a term and condition.
The proposed regulatory actions are specific to the HMS pelagic longline fishery that targets
tuna, swordfish, and pelagic sharks, and not any of the other fisheries under the HMS FMP or
Billfish FMP. As previously discussed, the June 14, 2001, opinion evaluated the entire HMS
FMP comprehensively, including all of its separately managed fisheries. The October 29, 2003,
opinion superceded the June 14, 2001, opinion, for the directed shark fisheries only. In a similar
manner, the proposed regulatory action would affect only the HMS pelagic longline fishery.
Thus, this opinion will only evaluate the HMS pelagic longline fishery in regard to their effects
on ESA-listed species under purview of NOAA Fisheries.
In summary, this reinitiated consultation evaluates the effects on listed species by the HMS
pelagic longline fishery: (1) as it is currently being prosecuted, including fishing under EFPs and
SRPs, and (2) as it would be prosecuted under the proposed regulations that require new sea
turtle bycatch and mortality reduction measures. The effects of the proposed rule to implement
the 2002 ICCAT swordfish quota recommendations are also evaluated in this consultation. For
the HMS pelagic longline fishery, this opinion will supersede the June 14, 2001, opinion. There
is no new information suggesting that the manner or extent of effects to any listed species from
the remaining fisheries under the HMS FMP (i.e., purse seine, harpoon, hand line, rod-and-reel
1-6

fisheries) has changed. Reinitiation of consultation is not required for those fisheries, and the
June 14, 2001, opinion and its no-jeopardy conclusion still apply for those fisheries.
2.0

DESCRIPTION OF THE PROPOSED ACTION

The HMS Division proposes to promulgate regulations for the continued authorization and
management of the HMS pelagic longline fishery for tunas and swordfish. The action would
modify the HMS FMP and regulations at 50 CFR part 635 under the authority of MagnusonStevens Fishery Conservation and Management Act (MSA) and the Atlantic Tunas Convention
Act (ATCA). The MSA is the principle federal statute governing the management of U.S.
marine fisheries. The management units covered under the HMS FMP consist of the populations
of swordfish (Xiphias gladius), bluefin tuna (Thunnus thynnus), yellowfin tuna (T. albacares),
bigeye tuna (T. obesus), albacore tuna (T. alalunga), skipjack tuna (Katsuwonus pelamis), and
the species of sharks that inhabit the western North Atlantic Ocean. The management units and
fishing activity for these species extend across federal, state, and international jurisdictional
boundaries. For the purposes of the FMP, each stock is identified as “Atlantic” (i.e., Atlantic
bluefin tuna). Tunas and swordfish are also subject to recommendations made by ICCAT, which
is responsible for the international conservation and management of tuna and tuna-like fishes.
The ATCA provides the authority to issue regulations may be necessary and appropriate to
implement ICCAT recommendations.
The authority to develop fishery management plans, including the HMS FMP, is established by
the MSA. The goal of the HMS FMP is to maximize to the region and nation the net benefits of
the fisheries regulated by the FMP. Some of the objectives stated in the FMP are summarized as
follows:
•
•
•
•

•

•

to rebuild overfished stocks
to avoid and reduce bycatch and bycatch mortality
to establish a foundation for international negotiation on conservation and management
measures to rebuild overfished fisheries
to better coordinate domestic conservation and management of the fisheries for Atlantic
tunas, swordfish, sharks, and billfish, considering the multi-species nature of many HMS
fisheries, overlapping regional and individual participation, international management
concerns, and other relevant factors
to develop eligibility criteria for participation in the shark and swordfish fisheries based
on historical participation, including access for traditional swordfish handgear fishermen
to participate fully as the stock recovers, and
to create a management system to make fleet capacity commensurate with resource status
so as to achieve the dual goals of economic efficiency and biological conservation.

NOAA Fisheries is required to avoid and reduce fishing bycatch and bycatch mortality to the
extent practicable under national and international laws and agreements, including the MSA, the
Marine Mammal Protection Act (MMPA), the ESA, and through recommendations of ICCAT.
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In recent years, NOAA Fisheries has taken action to avoid jeopardy of Atlantic sea turtles in the
HMS fisheries by implementing measures to mitigate mortality and minimize bycatch (see
Section 1.0, Consultation History). The MSA further requires NOAA Fisheries to minimize the
adverse economic impacts of regulations on fishing communities to the extent practicable.
The proposed regulations are necessary to reduce bycatch and bycatch mortality of sea turtles
caught incidentally in the Atlantic HMS pelagic longline fishery, consistent with the
requirements of the ESA, and to implement the 2002 ICCAT swordfish quota recommendations.
Summary information describing the HMS pelagic longline fishery and the proposed regulations
is presented below. Further detail regarding the proposed regulations can be found in the
proposed rule and DSEIS. Additional information on the HMS pelagic longline fishery and the
status of target species stocks can be found in numerous other documents, including the Final
HMS FMP Volumes I, II, and III (April 1999), 15 CFR Part 902 and 50 CFR Part 635 et al.,
Amendment 1 to the Atlantic Billfish Fishery Management Plan (April 1999), Regulatory
Amendment One to the HMS FMP (NMFS 2000a), and the 2000 - 2004 Stock Assessment and
Fishery Evaluation Reports.
2.1

Description of the HMS Pelagic Longline Fishery

U.S. pelagic longline fishermen began targeting highly migratory species in the Atlantic Ocean in
the early 1960s. U.S. landings of swordfish did not exceed 1,500 metric tons until the mid1970s. The gear used in the fishery has evolved over time. Presently, fishermen use
monofilament mainline that is rigged with various hook and float configurations depending on
whether the target is tunas or swordfish. Pelagic longline fishermen locate fish by looking for
temperature fronts between cooler and warmer water masses and typically set the gear across
these breaks. These temperature fronts are often associated with currents, specifically the Gulf
Stream Current, thus much of the fishing effort is associated with the edges of these currents. In
recent years, the availability of high resolution satellite-generated sea surface temperature data
has greatly influenced landings.
The HMS pelagic longline fishery primarily targets swordfish, yellowfin tuna, or bigeye tuna in
various areas and seasons. Secondary marketable species include dolphin; albacore tuna; and
pelagic sharks including mako, thresher, and porbeagle sharks; as well as several species of large
coastal sharks. Permit holders range from Maine to Texas, and fishing techniques vary by region
according to target species. The HMS pelagic longline fishery is comprised of five relatively
distinct segments, including the: Gulf of Mexico yellowfin tuna fishery; southern Atlantic
(Florida East Coast to Cape Hatteras) swordfish fishery; mid-Atlantic and New England
swordfish and bigeye tuna fishery; U.S. Atlantic Distant Water swordfish fishery; and Caribbean
tuna and swordfish fishery. In addition to geographical distinctions, these segments contribute
differing percentages of various target and non-target species. The different segments also use
differing gear types, bait, and deployment techniques. Fishing characteristics are dependent on a
specific vessel’s range capabilities based on fuel capacity, hold capacity, size, and construction.
Some vessels fish in more than one segment, targeting different species during the course of the
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2-3

The number of hooks per set varies with line configuration and target catch (Table 2.1.1). In
recent years, the HMS pelagic longline fishery has used “J” hooks almost exclusively. When
targeting swordfish, the lines generally are deployed at sunset and hauled at sunrise to take
advantage of swordfish nocturnal near-surface feeding habits (Berkeley et al.1981). Some
fishing captains preferentially target swordfish during periods when the moon is in its full or
waxing phase to take advantage of increased densities of pelagic species near the surface. Other
captains prefer fishing on the new moon phase, but again while the moon is waxing. Pelagic
longlines targeting tunas (primarily yellowfin) are set in the morning (pre-dawn) , deeper in the
water column, and hauled in the evening.
Table 2.1.1

Average Number of Hooks per pelagic longline set, 1995-2002.
Source: Longline logbook data.

Target Species

1995

1996

1997

1998

1999

2000

2001

2002

Swordfish

539

529

550

563

521

550

625

695

Bigeye Tuna

752

764

729

688

768

454

671

755

Yellowfin Tuna

721

679

647

685

741

772

731

715

Mix of tuna species

NA

NA

NA

NA

NA

638

719

767

Mix of species

658

695

713

726

738

694

754

756

2.1.2

Pelagic Longline Target Species
2.1.2.1 Swordfish

Swordfish (Xiphias gladius) are large migratory predators that are distributed globally in tropical
and subtropical marine waters. In the western Atlantic, swordfish range from Canada to
Argentina. These large pelagic fishes feed throughout the water column on a wide variety of prey
including groundfish, pelagics, deep-water fish, and invertebrates. Swordfish show extensive
diel migrations and are typically caught on pelagic longlines at night when they feed in surface
waters. Their broad distribution, large spawning area, and prolific nature have contributed to the
resilience of the species in spite of the heavy fishing pressure being exerted on it by many
nations. During their annual migration, north Atlantic swordfish follow the major currents that
circle the north Atlantic Ocean (including the Gulf Stream, Canary and North Equatorial
Currents), and the currents of the Caribbean Sea and Gulf of Mexico. The primary habitat in the
western north Atlantic is the Gulf Stream, which flows northeasterly along the U.S. coast then
turns eastward across the Grand Banks, the primary area within the NED where HMS pelagic
longlining occurs. North-south movement of swordfish along the eastern seaboard of the United
States and Canada is significant (SAFMC 1990).
In 2002, the estimated swordfish catch by U.S. vessels in the western Atlantic, including dead
discards, was 2,708.7 metric tons (mt) (NOAA Fisheries 2003). This represents a modest
increase of 55.4 mt from 2001, but a 22.5 percent decrease from 2000. The pelagic longline
2-4

fishery operates year-round in all pelagic waters of the U.S. EEZ and beyond, and currently
accounts for approximately 98 percent of the U.S. domestic swordfish landings. About 16 to 31
percent of U.S. swordfish landings are harvested on the Grand Banks.
NOAA Fisheries believes that the existing license limitation system and restrictions on upgrading
to a higher license class has capped the number of U.S. vessels fishing on the Grand Banks and
effort has decreased. The NOAA Fisheries Pelagic Logbook Newsletter reports that 22 U.S.
vessels fished on the Grand Banks in 1996 and 1997 (making 710 and 762 sets, respectively),
and only 15 U.S. vessels fished on the Grand Banks 1998 (618 sets). Beideman (2001, pers.
comm.) reported that in the 1990s there were more than 60 longline vessels fishing the Grand
Banks, but only 10-12 vessels fished there in 2000. It appears that pelagic longline effort in the
Grand Banks has steadily decreased over the past few years, but there is a possibility for a
change.
Effective December 3, 2003, an agreement between Canada and the United States allows U.S.
fishermen to apply for a license to conduct activities in Canadian waters and ports. This
agreement may lead to additional effort in the NED in excess of projected levels. Additional
vessels may participate in the fishery, or there may be an increased number of trips because of a
shortened steaming time to and from Canadian ports. These potential increases in effort are not
quantifiable at this time. However, data over the last six years indicate that less than 12 vessels,
on average, fished in the NED. NOAA Fisheries will monitor effort in the NED and modify its
management strategy as appropriate.
2.1.2.2 Atlantic Tuna
Tunas are highly migratory fish found in many of the world’s tropical, subtropical, and temperate
ocean regions. Bluefin (Thunnus thynnus), bigeye (Thunnus obesus), albacore (Thunnus
alalunga) and skipjack (Katsuwonus pelamis) tunas are widely distributed throughout the
Atlantic. Yellowfin tuna (Thunnus albacores) are considered to be a more tropical species.
Smaller yellowfin tuna form mixed schools with skipjack tuna and juvenile bigeye tuna and are
mainly limited to surface waters, whereas larger yellowfin tuna are found in surface and subsurface waters. Bigeye tuna inhabit waters deeper than those of any other tuna species and
undertake extensive vertical movements. Albacore tuna also tend to inhabit deep waters, except
when young. Many of these tunas are opportunistic feeders, eating mainly fish and squid (SCRS
1999). Commercial and recreational fishermen from numerous countries participate in fisheries
for several species of Atlantic tuna.
In 2002, the estimated tuna catch by U.S. pelagic longline vessels in the western Atlantic,
including dead discards, was 3,252 metric tons (mt) (NOAA Fisheries 2003). Yellowfin tuna
dominated tuna landings by weight (2,542 mt), with the pelagic longline fishery accounting for
approximately 43 percent of those landings.

2-5

2.1.2.3 Pelagic Sharks and Other Finfish
Pelagic sharks are commonly caught by the pelagic longline fishery. Pelagic sharks include the
following species that are commonly caught on pelagic longlines: shortfin mako, porbeagle,
common thresher, and blue sharks. Other pelagic shark species, such as longfin mako, sixgill,
bigeye sixgill, and sevengill sharks are occasionally or rarely taken. Several commercially
valuable species of finfish are also caught by the pelagic longline fishery, including dolphin
(Coryphaena hippurus), and wahoo (Acanthocybium solanderi).

2.1.3

U.S. Atlantic Pelagic Longline Fishery Catches Catch in Relation to International
Catches

Table 2.1.3 A summarizes the total catch (in numbers) of important species caught during 1995
through 2002 in the U.S. pelagic longline fishery.

2-6

Table 2.1.3 A
Species

Reported catch of species caught by U.S. Atlantic pelagic longlines, in
number of fish 1995-2002. Reported in pelagic longline logbook.
1995

1996

1997

1998

1999

2000

2001

2002

Swordfish Kept

72,788

73,111

68,274

68,345

64,370

60,101

49,220

49,360

Swordfish
Discarded

29,789

23,831

20,613

22,579

20,066

16,711

14,448

13,039

Blue M arlin
Discarded

3,091

3,310

2,614

1,291

1,248

338

164

401

White M arlin
Discarded

3,432

2,924

2,812

1,490

1,971

504

295

709

Sailfish Discarded

1,195

1,443

1,766

827

1,404

517

61

158

Spearfish
Discarded

445

553

390

105

156

79

29

51

Bluefin Tuna
Kept

239

209

180

206

239

232

183

178

Bluefin Tuna
Discarded

2,852

1,709

688

1,304

601

737

348

593

120,548

85,964

102,798

75,268

99,957

94,677

82,973

80,104

Pelagic Sharks
Kept

5,885

5,270

5,134

3,624

2,705

2,932

3,511

2,997

Pelagic Sharks
Discarded

90,173

84,330

82,220

44,000

28,910

26,281

23,953

22,844

Large Coastal
Sharks Kept

57,676

36,022

21,382

8,742

1,025

7,752

6,510

4,077

Large Coastal
Sharks Discarded

11,013

10,403

8,243

5,908

5,774

6,800

4,891

3,815

Dolphin Kept

72,463

35,888

62,811

21,864

29,902

28,095

27,913

30,452

Wahoo Kept

4,976

3,635

4,570

4,303

4,112

3,887

3,084

4,212

Sea Turtles
Discarded

1,142

498

267

885

627

270

421

465

11,064

10,657

9,861

7,676

7,488

7,570

7,740

7,151

Bigeye, Albacore,
Yellowfin,
Skipjack Tunas
Kept

Number of Hooks
(X 1,000)

2-7

The U.S. HMS fleet is a small part of the international fleet that competes on the high seas for
catches of tunas and swordfish (Table 2.1.3 B). In 1990, the U.S. fleet landed as much as 35
percent of the swordfish from the north Atlantic, north of 5o N latitude, but this proportion
decreased to 25 percent by 1997. For tunas, the U.S. proportion of landings was 23 percent in
1990, decreasing to 16 percent by 1997. The U.S. fleet accounts for almost none of the landings
of swordfish and tuna from the Atlantic Ocean south of 5o N latitude, and it does not operate in
the Mediterranean Sea. Tuna and swordfish landings by foreign fleets operating in the tropical
Atlantic and Mediterranean are greater than the catches from the north Atlantic area where the
U.S. fleet operates. Within the area where the U.S. fleet operates, the U.S. portion of fishing
effort (in numbers of hooks fished) is less than 10 percent of the international fleet’s effort. Even
this low estimate may be inflated because of differences in effort reporting methods among
ICCAT countries (NMFS SEFSC 2001).
Because some ICCAT nations do not monitor incidental catches of sea turtles, it is not possible
to accurately assess the impact of international fishing efforts on sea turtles. However, high
absolute numbers of sea turtle catches by the foreign fleets have been reported from other sources
(NMFS SEFSC 2001, Lewison et al. 2004). If the sea turtle catch rates by foreign fleets are
similar to the catch rates of the American fleet, then the American fleet may represent less than
one-tenth, and certainly no more than one-third, of the total catch and mortality of sea turtles in
north Atlantic pelagic longline fisheries.

2-8

Table 2.1.3 B Estimated International Longline Landings of HMS, Other than Sharks, for
All Countries in the Atlantic: 1998-2002 (mt wet weight)*. Source: SCRS,
2003
1998

1999

2000

2001

2002

Swordfish (N .Atl + S. Atl)

24,432

25,201

24,990

21,773

21,770

Yellowfin T una (W . Atl)**

8,795

11,596

11,465

12,535

12,141

Bigeye Tuna

71,825

76,513

70,902

54,842

43,773

764

914

859

610

727

Albacor e Tuna (N . Atl + S. Atl)

23,574

27,209

28,881

28,959

27,491

Skipjack T una (N. A tl + S. Atl)

99

51

60

70

88

2,519

2,359

2,187

1,638

1,247

918

981

893

592

705

1,058

524

811

812

1,050

Total

133,984

145,348

141,048

121,831

108,992

U.S. Lon gline Landin gs (from U .S.
Natl. Report, 2003)#

7,139.9

8,356.0

7,319.7

6,012.0

5893.2

5.3

5.7

5.2

4.9

5.4

Bluefin T una (W . Atl.)**

Blue M arlin (N. Atl. + S. Atl.)***
White M arlin (N. Atl. + S. Atl.)***
Sailfish (W. A tl.)***

U.S. Longline Landings as a
Percent of Total Longline Landings

* Landings include those classified by the SCRS as longline landings for all areas
** Note that the United States has not reported participation in the E. Atl yellowfin tuna fishery since 1983 and has
not participated in the E. Atl bluefin tuna fishery since 1982.
***Includes U .S. dead discard s.
# Includes swordfish longline disca rds and bluefin tuna discards.

2.1.4

Management of the HMS Longline Fishery

Pelagic longlines are a highly regulated gear type due to the nature of the gear and its catch and
bycatch. Minimum sizes are established for yellowfin, bigeye, and bluefin tuna, and swordfish to
reduce the mortality of small fish. There are target species catch limits associated with a vessel’s
ability to retain bluefin tuna. Billfish regulations prohibit the retention of billfish by commercial
vessels, or the sale of billfish taken from the Atlantic; therefore, all billfish must be discarded.
Regulatory discards compose a large portion of the bycatch in the fishery. In some areas and at
certain times of the year, much of the bycatch in this fishery is released dead. Because it is
difficult for pelagic longline fishermen to effectively avoid undersized fish or other regulatory
discards in some areas, NOAA Fisheries has closed areas in the Gulf of Mexico and along the
east coast of the U.S. (see Figure 2.3.1.C). The intention of these closures is to relocate some of
the fishing effort into areas where bycatch is expected to be lower. To facilitate enforcement of
the time/area closures, all pelagic longline vessels are required to use vessel monitoring systems
(VMS), which report the location of the vessel at all times.
2-9

In addition to regulations designed to reduce bycatch, pelagic longline fishermen are subject to
quota management for swordfish, sharks, and bluefin tuna. Quota monitoring requires seasonal
regulations and closures. To document catch and effort, since 1992, pelagic longline fishermen
have been subject to permitting and reporting requirements, including logbooks and observer
coverage. The pelagic longline reporting program is managed by the SEFSC. In 1999, NOAA
Fisheries established a limited entry system for swordfish, shark, and tuna longline category
permits. Pelagic longline fishermen who target swordfish or BAYS (Bigeye, Albacore,
Yellowfin, Skipjack) tunas must possess swordfish, shark, and tuna longline category permits.
NOAA Fisheries is currently re-evaluating the limited access program and may consider gearspecific permits in the future. As of November 2003, approximately 235 tuna longline limited
access permits had been issued. In addition, approximately 203 directed swordfish limited access
permits had been issued.
HMS fish dealers are also subject to reporting requirements. NOAA Fisheries has extended
dealer permitting and reporting requirements to all swordfish importers as well as dealers who
buy domestic swordfish taken from the Atlantic. These data are used to evaluate the impacts of
harvesting on the stock and the impacts of regulations on affected entities.
2.1.5

Management of HMS Pelagic Longline Fishing EFPs and SRPs

Every year, NOAA Fisheries issues a small number of exempted fishing permits (EFPs) and
scientific research permits (SRPs) under the MSA, authorizing the collection of a limited number
of HMS from federal waters in the Atlantic Ocean using pelagic longline gear. These catches are
for the purposes of scientific data collection and/or public display. On November 10, 2003,
NOAA Fisheries issued a final rule that modified regulations for HMS fishing activities
conducted under EFPs and SRPs (68 FR 63738). The new regulations are intended to improve
accountability of these fishing activities through increased monitoring and additional reporting
requirements. Under these regulations (effective December 10, 2003):
•
EFP holders must notify their local NOAA Fisheries Office for Law Enforcement at least
24 hours prior to departure for all fishing trips conducted to collect HMS for the purpose
of public display;
•
All live HMS retained for the purpose of public display must be tagged while still on
board the fishing vessel with either a conventional dart tag or a microchip Passive
Integrated Transponder (PIT) tag, both of which will be supplied by NOAA Fisheries;
•
If warranted, NOAA Fisheries may specify conditions for conducting fishing activities to
collect HMS for public display to minimize mortalities of either targeted or bycatch
species;
•
NOAA Fisheries reserves the right to place an at-sea observer on board an authorized
HMS collection vessel;
•
EFP and SRP holders must report all HMS collection activities regardless of whether they
occur inside or outside the Exclusive Economic Zone (EEZ);
•
Negative reports must be submitted for months when no HMS are collected;

2-10

•

•
•

To obtain a new permit, applicants for EFP and SRP renewals must include with the
application the previous year’s year-end report and any delinquent reports for permits
issued in prior years;
For the pelagic longline directed swordfish fishery, separate EFPs are no longer required
to delay offloading swordfish for vessels equipped with an operational VMS; and
Several prohibitions are established concerning the submission of false information and
violations of the terms and conditions of EFPs and SRPs to facilitate enforcement of EFP
application and reporting requirements.

Many of the EFPs and SRPs involve fishing with pelagic longline gear by commercial or
research vessels, similar or identical to the fishing methods of the pelagic longline fishery, which
is the primary object of this opinion. In those cases, the types and rates of interactions with listed
species from the EFP or SRP activity would be expected to be similar to those from the larger
pelagic longline fishery. If the fishing type is similar, and the associated fishing effort does not
represent a significant increase over the effort levels for the overall fishery considered in this
opinion, then issuance of some EFPs or SRPs would be expected to fall within the level of effort
and impacts considered in this opinion. For example, issuance of an EFP to an active
commercial vessel likely does not add additional effects than would otherwise accrue from the
vessel’s normal commercial activities. Also, issuance of an EFP to a research vessel to conduct a
limited number of pelagic longline sets likely would not add sufficient fishing effort to produce a
detectable change in the overall amount of fishing effort in a given year. With the improved
monitoring and reporting of EFPs and SRP fishing activities as a result of the December 10,
2003, regulations, reported fishing effort, and any associated listed species turtle takes, will be
documented. Those data will be combined with the HMS pelagic longline fishery data. Any
impacts on protected species from EFP and SRP fishing activities, therefore, can be included in
bycatch analysis for the HMS pelagic longline fishery. Therefore, we consider the issuance of
some EFPs and SRPs by HMS Division to be within the scope of this opinion. The included
EFPs and SRPs would be those that involve fishing with pelagic longline gear, consistent with
the requirements of section 2.2 below, and that are not expected to increase fishing effort
significantly.
HMS Division may consider issuance of EFPs or SRPs meeting these conditions to be covered
by this consultation, and takes of sea turtles would be included against the authorized take levels
of this opinion. HMS Division must minimize sea turtle bycatch and bycatch mortality from
EFP and SRP fishing activities by specifying permit conditions similar to the requirements under
which the HMS pelagic longline fishery operates (e.g., hook type, handling and release
equipment). If in doubt whether a particular EFP or SRP is consistent with this consultation,
HMS Division should seek the concurrence of SERO. For EFPs and SRPs that are not covered
under this consultation, separate consultation, pursuant to section 7 of the ESA, may be required
prior to issuance of the permits.

2-11

2.1.6

Pelagic Observer Program

The SEFSC Miami Laboratory has been responsible for the administration of the Pelagic
Observer Program (POP) since 1992. NOAA Fisheries places observers aboard HMS-permitted
vessels under the authority of the MSA, as well as the MMPA and ESA. The objective and
mission of the POP is to document the effort, directed catch, and bycatch, as well as collect data
on species morphometrics and biological characteristics. Additionally, the program documents
fishery interactions with marine mammals, sea turtles, and birds. The observer data are used to
estimate catch of target species, bycatch of non-target species, and the incidental take of
protected species.
Observer coverage is based on number of sets reported by the U.S. pelagic longline fleet in the
eleven statistical reporting areas (Figure 2.3.1.C) of the North Atlantic Ocean (north of 5 deg. N
latitude). Vessels are issued a certified letter prior to the start of a calendar quarter indicating
that they have been randomly chosen for observer coverage and must schedule an observer trip
with the POP within the quarter that the vessel was chosen. Five percent coverage was the
sampling target for the POP until 2002. The five percent level was required both for ICCAT
reporting and by the June 14, 2001, opinion. The sampling fraction has varied from 2.5 to more
than 5 percent, depending on available resources. In 2002, the POP raised their target coverage
level to 8 percent, to meet new ICCAT targets and to improve the precision of catch and bycatch
estimates specified in NOAA Fisheries’ guidelines for fisheries observer coverage levels (NMFS
2003). NOAA Fisheries strives to achieve coverage levels that will yield a 20-30 percent
coefficient of variation for bycatch estimates regarding protected species. In 2002, 856 pelagic
longline sets were observed and recorded by the POP (8.9 percent overall coverage: 100 percent
coverage in the NED experiment and 3.7 percent coverage in remaining areas). Table 2.3.6
compares the amount of observer coverage in past years for this fleet.

2-12

Table 2.3.6

Observer Coverage of the Pelagic Longline Fishery.
Source: Yeung (2001) and Garrison (2003a)

Year

Number of Sets Observed

Percentage of Total N umber of Sets

1995

696

5.2

1996

361

2.5

1997

448

3.1

1998

287

2.9

1999

420

3.8

2000

464

4.2

2001*

2002*

Total

Non-NED

NED

Total

Non-NED

NED

403

217

186

3.7

2.0

100.0

856

353

503

8.9

3.7

100.0

*In 2001 and 200 2, 100 p ercent ob server cov erage was re quired in the NED experime ntal fishery.

2.2

Proposed Regulations for the Atlantic Pelagic Longline Fishery

NOAA Fisheries is proposing new regulations for the Atlantic pelagic longline fishery to reduce
sea turtle bycatch and bycatch mortality (69 FR 6621, February 11, 2004). The multiple
objectives of the regulations, as stated in the DSEIS, are:
•
To be consistent with the objectives of the HMS FMP and all applicable laws;
•
To implement measures proven during the NED research experiment to reduce sea
turtle interactions;
•
To avoid jeopardizing the continued existence of leatherback and loggerhead sea
turtles by implementing new management measures within the U.S. Atlantic
pelagic longline fishery intended to reduce or, at a minimum, prevent increases in
incidental takes of sea turtles in this fishery and reduce the mortality associated
with such interactions;
•
To reconsider, in light of possible gear modifications, the NED closure and other
time/area closures; and,
•
To minimize, to the extent practicable, the economic impact of sea turtle bycatch
mitigation measures on U.S. pelagic longline fishery participants.
The proposed change in management regime under the HMS FMP would affect commercial
pelagic longline gear and fishermen targeting swordfish, tuna, and sharks. The DSEIS analyzed
numerous alternatives, representing the range of options considered by NOAA Fisheries, to
reduce the incidental catch and bycatch mortality of sea turtles in the pelagic longline fishery for
Atlantic HMS. The alternatives ranged from no action to a total prohibition of the gear type,
with alternatives A3 (hook and bait requirements outside the NED), A10 (hook and bait
requirements for fishing in the NED), and A16 (gear removal and handling requirements for sea
2-13

turtles), together, comprising NOAA Fisheries’ Preferred Alternatives in the proposed
regulations. As discussed in the Consultation History section of this opinion, those alternatives
have subsequently been modified. The alternatives currently under consideration for the final
rule are thus considered as part of the proposed action for this opinion.
NOAA Fisheries is also proposing to amend the regulations governing the North and South
Atlantic swordfish fisheries. The proposed changes would implement recommendations adopted
at the 2002 meeting of the ICCAT. These proposals are also considered part of the proposed
action for this opinion.
2.2.1

Hook and Bait Requirements Outside the NED (Alternative A5 (b))

NOAA Fisheries is considering modifying its preferred alternative for this action from A3 to A5
(b). Alternative A5 (b) would limit vessels with pelagic longline gear onboard, at all times, in all
areas open to pelagic longline fishing, excluding the NED, to possessing onboard and/or using
only 16/0 or larger non-offset circle hooks and/or 18/0 or larger circle hooks with an offset not to
exceed 10 degrees. Offsets must be set by the manufacturer and not by the fishermen. Only
whole finfish and squid baits may be possessed and/or utilized with allowable hooks. This
alternative would maintain the current requirement for possession or use of non-stainless steel
corrodible hooks, and the live-bait restriction in the western Gulf of Mexico.
2.2.2

Hook and Bait Requirements for Fishing inside the NED (Alternative A10 (b))

NOAA Fisheries is also considering modifying alternative A10 as A10 (b). Alternative A10 (b)
would re-open the NED to pelagic longline fishing and limit vessels with pelagic longline gear
onboard in that area, at all times, to possessing onboard and/or using only 18/0 or larger circle
hooks with an offset not to exceed 10 degrees. Only whole mackerel or squid baits may be
possessed and/or utilized with allowable hooks. This alternative would maintain the current
requirement for possession or use of non-stainless steel corrodible hooks.
2.2.3

Gear Removal and Handling Requirements for Sea Turtles to Reduce PostRelease Mortality (Alternative A16)

Alternative A16 would require vessel operators aboard all federally permitted vessels, or those
required to be permitted, for Atlantic HMS with pelagic longline gear on board to possess and
maintain line cutters and dipnets meeting newly revised design and performance standards.
Alternative A16 would also require vessel operators to possess, maintain, and utilize additional
sea turtle handling and release equipment and comply with handling and release guidelines, as
specified by NOAA Fisheries, to facilitate the removal of fishing gear from incidentally captured
sea turtles. The following additional or newly revised equipment would include:
A- (1) long-handled line cutter;
B- (1) long-handled dehooker for ingested hooks;
2-14

C- (1) long-handled dehooker for external hooks (the long-handled dehooker for ingested
hooks used for item B will also satisfy this requirement);
D- (1) long-handled device to pull an “Inverted V” (if 6’ J-style dehooker is used for item
C, it will also satisfy this requirement);
E- (1) dipnet;
F- (1) standard automobile tire;
G- (1) short-handled dehooker for ingested hooks;
H- (1) short-handled dehooker for removing external hooks (the short- handled dehooker
for ingested hooks used for item G will also satisfy this requirement);
I- (1) long-nose or needle-nose pliers;
J- (1) bolt cutter;
K- (1) monofilament line cutter; and,
L- (2) types of mouth openers/mouth gags.
The use of items A - D would be required when sea turtles cannot be boated. The use of items E
- L would be required when sea turtles can be boated. All equipment would be required to be
used in accordance with the handling and release guidelines specified by NOAA Fisheries.
2.2.4

Proposed Adjustment of Swordfish Quota

Consistent with ICCAT recommendations, proposed regulations would establish annual quotas
for North and South Atlantic swordfish, implement a dead discard allowance for the 2003 fishing
year and beyond, allow 200 mt wet weight (ww) of North Atlantic swordfish quota to be taken in
the area between 5 degrees North latitude and 5 degrees South latitude, and transfer 25 mt ww of
North Atlantic swordfish to Canada. Specifically, the proposed rule would:
•
•
•
•
•

2.3

Increase the United States North Atlantic swordfish quota to 3,877 mt ww in 2003 and
3,907 mt ww in 2004 and 2005;
Allow 200 mt ww of the North Atlantic swordfish catch limit to be harvested from an
area between 5 degrees North latitude and 5 degrees South latitude;
Allocate the United States an 80 mt ww dead discard allowance in addition to the country
specific quota allocation for North Atlantic swordfish;
Transfer 25 mt ww of North Atlantic swordfish quota to Canada in 2003, 2004, and 2005;
and
Allocate the United States 100 mt ww of South Atlantic swordfish quota in 2003, 2004,
and 2005 and 120 mt ww in 2006.
Action Area

The action area for a biological opinion is defined as all the areas affected directly or indirectly
by the federal action and not merely the immediate area involved in the action (50 CFR 402.02).
The HMS pelagic longline fishery operates in large areas of the Gulf of Mexico, the Caribbean

2-15

Sea, and the Atlantic Ocean, ranging throughout the U.S. EEZ and beyond. Figures 2.3.1. A and
B illustrate the wide ranging nature of the longline fishery throughout the western North Atlantic.
Figure 2.3.1. C shows the statistical reporting areas for the HMS pelagic longline fishery and the
existing regulatory closure areas. Area E (the NED) would be reopened to fishing under the
proposed regulations. Close examination of Figures 2.3.1.A and B reveals that HMS pelagic
longline vessels occasionally have reported sets or even observed sets in the closed areas, where
their fishing was illegal, and in the EEZs of other nations under chartering arrangements. The
HMS Division is currently aware of only three vessels that have, over the past year or two, fished
under such arrangements off of Namibia, Brazil, and Uruguay. Based on that information, the
HMS Division currently estimates that less than 10 HMS-permitted vessels may participate in
chartering arrangements. HMS-permitted vessels fishing under a charter arrangements are still
subject to U.S. regulations, including all monitoring and reporting requirements, unless otherwise
exempted under exempted fishing permits. NOAA Fisheries recently published a proposed rule
to establish chartering permits to better monitor such activities (69 FR 25357).
With the requirement that all longline vessels carry VMS, NOAA Fisheries’ Office of
Enforcement will now be able to detect and prosecute illegal incursions into closed areas or other
nation’s EEZs. In the future, therefore, we expect that the vast majority of longline fishing by the
U.S. fleet will occur within areas of the U.S. EEZ and the high seas that are open to U.S.
longliners, and on very rare occasions, in other nation’s EEZ under a legal charter agreement.
Throughout their wide-ranging fishing grounds, HMS fisheries may interact with listed species of
sea turtles; therefore, the action area for this opinion includes all of these areas.

2-16

Figure 2.3.1 A and B. Pelagic longline fishing effort during 2001 (A) and 2002 (B).
Locations of observed (dark circles) and reported (light circles) sets are indicated.

2-17

Figure 2.3.1 C. Pelagic longline fishing areas in the north Atlantic ocean indicating 11
defined fishing areas. CAR =Caribbean, GOM = Gulf of Mexico, FEC = Florida East Coast,
SAB = South Atlantic Bight, SAR = Sargasso Sea, MAB = Mid-Atlantic bight, NEC =
Northeast Coastal, NED = Northeast Distant, NCA = North Central tlantic, TUN = Tuna
North, TUS = Tuna South. Pelagic longline closed areas are indicated by shaded
polygons and letter labels (A-E). (Garrison 2003a)

2-18

3.0 STATUS OF LISTED SPECIES, CRITICAL HABITAT, AND ENVIRONMENTAL
BASELINE
3.1

List of Species and Critical Habitat

The following endangered and threatened species and designated critical habitat occur in the
action area, as defined in Section 2.3, and may be affected by the proposed action.
Marine Mammals
Blue whale (Balaenoptera musculus)
Humpback whale (Megaptera novaeangliae)
Fin whale (Balaenoptera physalus)
Northern right whale (Eubalaena glacialis)
Sei whale (Balaenoptera borealis)
Sperm whale (Physeter macrocephalus)

Status
Endangered
Endangered
Endangered
Endangered
Endangered
Endangered

Sea turtles
Leatherback sea turtle (Dermochelys coriacea)
Hawksbill sea turtle (Eretmochelys imbricata)
Green turtle (Chelonia mydas)
Kemp’s ridley sea turtle (Lepidochelys kempii)
Loggerhead sea turtle (Caretta caretta)
Olive ridley turtle (Lepidochelys olivacea)

Endangered
Endangered
Endangered/Threatened
Endangered
Threatened
Threatened

Fish
Smalltooth sawfish (Pristis pectinata)
Gulf of Maine Atlantic salmon

Endangered
Endangered

Critical Habitat
Northern Right Whale (Eubalaena glacialis)

Endangered

*Green sea turtles in U.S. waters are listed as threatened except for the Florida breeding
population, which is listed as endangered. Due to the inability to distinguish between the
populations away from the nesting beaches, green sea turtles are considered endangered
wherever they occur in U.S. waters.
3.2

Analysis of the Species and Critical Habitat Not Likely to be Adversely Affected

We have determined that the proposed action being considered in this opinion is not likely to
adversely affect the following listed species or critical habitat under the ESA: blue whale, sei
whale, humpback whale, fin whale, Northern right whale, sperm whale, smalltooth sawfish, or
right whale critical habitat. These species and critical habitat are therefore excluded from further

3-1

analysis and consideration in this opinion. The following discussion summarizes our rationale
for these determinations and conclusions.
3.2.1

Whales

Blue, sei, and sperm whales are predominantly found in offshore waters where pelagic longline
fishing targeting HMS occurs. Observed or reported interactions between any of these species
and pelagic longline gear are rare. There has been one observed entanglement of a sperm whale
in the Hawaii-based Pacific pelagic longline fishery; that animal was released without any
hooking injury or any trailing gear. Sperm whales have also been observed during hauling
operations for longline fisheries in the southern hemisphere but there were no confirmed
entanglements (Ashford et al. 1996; Nolan et al. 2000). With respect to the U.S. Atlantic pelagic
longline fishery, the final Atlantic Offshore Cetacean Take Reduction Plan and a report by Scott
and Brown (1997) stated that there is no evidence of interactions with offshore large whales. In
the 12 years that NOAA Fisheries observers have been collecting data in the Atlantic longline
fishery (observer coverage based on 5 percent of the total reported sets and 100 percent observer
coverage during the NED experimental fishery 2001-2002), there have been no documented
interactions between this pelagic longline fishery and offshore large whales. In 2003, however, a
baleen whale was incidentally entangled in pelagic longline gear used in the NED experimental
fishery. The fishery observer was unable to definitively identify or photograph the animal, so it
is not known if it was a listed or unlisted species. However, it is reasonable to believe that this
was an ESA-listed species based on the baleen whale species whose range overlaps with the
operation of the fishery. The observer was able to document that the animal was released alive
with no gear left on the animal. Although the Atlantic Scientific Review Group (ASRG) has not
yet made a “serious injury” determination for this event in accordance with the Marine Mammal
Protection Act, based on the serious injury determination criteria for marine mammals (Angliss
and DeMaster, 1998), the “unidentified” whale was likely unharmed, with no chance of postrelease mortality.
Northern right, fin, and humpback whales are more coastal in their distribution, although they
can occur in offshore areas as well. We believe that, because of their more coastal distribution,
right, fin, and humpback whales are even less likely to interact with the longline fishery than the
offshore large whales. There have been no reported or documented interactions between these
whales species and the Atlantic pelagic longline fishery. Given their more coastal distribution, it
is unlikely that the 2003 unidentified baleen whale was one of these species.
Because Northern right, fin, humpback, blue, sei, and sperm whales occur in the action area, we
acknowledge there is a possibility of interaction with the longline fishery. The available
evidence indicates interactions are exceedingly rare, and in two of the three known cases, noninjurious. There is only one documented interaction that may have been injurious (a humpback
whale that was released with trailing gear), and that was the result of a near-coastal set in the
Pacific. Most near-coastal areas are closed to pelagic longline fishing in the Atlantic. We
believe the chances of a fin, humpack, Northern right, blue, sei, or sperm whale being adversely
3-2

affected by the Atlantic pelagic longline fishery in the foreseeable future are discountable. We
conclude the proposed action is not likely to adversely affect these species, and these species will
not be considered further in this opinion.
3.2.2

Fish

The endangered Gulf of Maine Atlantic salmon distinct population segment (DPS) includes the
wild population of Atlantic salmon found in rivers and streams from the lower Kennebec River
north to the U.S.-Canada border. These include the Dennys, East Machias, Machias, Pleasant,
Narraguagus, Ducktrap, and Sheepscot Rivers and Cove Brook. Atlantic salmon are an
anadromous species. Spawning and juvenile rearing occur in freshwater rivers followed by
migration to the marine environment. Juvenile salmon in New England rivers typically migrate
to sea in May after a two to three year period of development in freshwater streams. The salmon
remain at sea for two winters before returning to their U.S. natal rivers to spawn from mid
October through early November. While at sea, salmon generally undergo extensive migrations
in the Northwest Atlantic to waters off Canada and Greenland, thus, they are widely distributed
seasonally over much of the region. Captures of wild Atlantic salmon in U.S. commercial
fishing or by research/survey operations are rare. There have been a few reported taken by trawls
in the Gulf of Maine and southern New England, but there are no records since 1992. An adult
salmon caught by a commercial fishing vessel in 2001 was subsequently determined to be an
escaped aquaculture fish. Based on this information, it is highly unlikely that the action being
considered in this opinion will affect the Gulf of Maine DPS of Atlantic salmon. This species
will not be considered further in this opinion.
Smalltooth sawfish historically occurred commonly in the shallow waters of the Gulf of Mexico
and along the eastern seaboard as far north as North Carolina, with rare records of occurrence as
far north as New York. The smalltooth sawfish range has subsequently contracted to
predominantly peninsular Florida and, within that area, they can only be found with any
regularity off the extreme southern portion of the state. Smalltooth sawfish are generally shallow
warm-water fish, known to spend most of their time at or near the bottom of inshore bars,
mangrove edges, and seagrass beds. Younger (smaller) animals are believed to be restricted to
shallow depths; however, larger animals roam over a much greater depth range, with records
from as deep as over 70 m.
In the 14 years that NOAA Fisheries observers have been collecting data in the Atlantic longline
fishery, there have been no documented interactions between the HMS pelagic longline fishery
and smalltooth sawfish. The only areas where smalltooth sawfish are likely to occur in the
Atlantic EEZ are off the coast of Florida and northern Georgia. Since March 1, 2001, the waters
off the east coast of Florida have been closed to HMS pelagic longline fishing year-round, and
the Charleston Bump, which encompasses federal waters off of Georgia, is closed seasonally to
HMS pelagic longline fishing (see Figure 2.3.1. C). Based on the rarity of smalltooth sawfish in
federal waters where HMS pelagic longline fishing occurs, their benthic habits, and the absence
of records in observer data, it is highly unlikely that the action being considered in this opinion
3-3

will affect the smalltooth sawfish. Thus, this species will not be considered further in this
opinion.
3.2.3

Northern Right Whale Critical Habitat

Northern right whale critical habitat (50 FR 28793) has been designated in the action area in the
following general areas: (1) coastal Florida and Georgia, (2) the Great South Channel, east of
Cape Cod, (3) Cape Cod Bay and Massachusetts Bay. The closure of the Florida East Coast area
to longline fishing almost totally eliminates the coastal Florida and Georgia critical habitat area
from the action area. The remaining critical habitat areas that are not closed to longline fishing
are shallow, coastal areas that are not used by the longline fishery (see Figures 2.3.1. A and B).
The environmental features (typically referred to as the primary constituent elements) of the
critical habitat areas relate to water depth, water temperature, bathymetry, and food availability.
Pelagic longline gear, even if used in the critical habitat areas, will have no impact on these
features. Thus, the proposed action will not adversely affect the constituent elements of
designated critical habitat for the North Atlantic right whale.
3.3

Analysis of the Species Likely to be Adversely Affected

The following subsections are synopses of the current state of knowledge on the life history,
distribution, and population trends of sea turtle species which may be affected by the proposed
action. Additional background information on the range-wide status of these species can be
found in a number of published documents, including: recovery plans for the U.S. population of
loggerhead sea turtles (NMFS and USFWS 1991b), Kemp’s ridley sea turtle (USFWS and
NMFS 1992), green sea turtle (NMFS and USFWS 1991a), hawksbill sea turtle (NMFS and
USFWS 1993), and leatherback sea turtle (NMFS and USFWS 1992); Pacific Sea Turtle
Recovery Plans (NMFS and USFWS, 1998a-e) and sea turtle status reviews and biological
reports (NMFS and USFWS 1995; Marine Turtle Expert Working Group (TEWG) 1998 & 2000,
NMFS SEFSC 2001). Further information for olive ridley sea turtles can also be found at:
http://www.nmfs.noaa.gov/prot_res/species/turtles/olive.html and
http://northflorida.fws.gov/SeaTurtles/Turtle%20Factsheets/olive-ridley-sea-turtle.htm
Green, leatherback, loggerhead, hawksbill, Kemp’s ridley, and olive ridley sea turtles are highly
migratory or have migratory phases in their life history. As a result, they are exposed to a
multitude of fisheries in which they can be caught and injured, as well as other sources of
anthropogenic mortality throughout their range, such as vessel traffic. In addition to
anthropogenic factors, natural threats to nesting beaches and marine habitats such as coastal
erosion, seasonal storms, predators, and temperature variations also affect the survival and
recovery of sea turtle populations. As a result, sea turtles still face many of the original threats
that were the cause of their listing under the ESA.
These subsections focus primarily on the Atlantic Ocean populations of sea turtle species since
these are the populations that may be directly affected by the proposed action. However, because
3-4

these species are listed as global populations (with the exception of Kemp’s ridleys and Florida
greens, whose distribution is entirely in the Atlantic), the global status and trends of these species
are included to provide a basis and frame of reference for our final determination of the effects of
the proposed action on the species as listed under the ESA.
3.4.1

Loggerhead Sea Turtle

The loggerhead sea turtle was listed as a threatened species throughout its global range on July
28, 1978. It was listed because of direct take, incidental capture in various fisheries, and the
alteration and destruction of its habitat. Loggerhead sea turtles inhabit the continental shelves
and estuarine environments along the margins of the Atlantic Ocean, Pacific Ocean, Indian
Ocean, Caribbean Sea and Mediterranean Sea. In the Atlantic, developmental habitat for small
juveniles is the pelagic waters of the North Atlantic and the Mediterranean Sea (NMFS and
USFWS 1991b). Within the continental United States, loggerhead sea turtles nest from Texas to
New Jersey. Major nesting areas include coastal islands of Georgia, South Carolina, and North
Carolina, and the Atlantic and Gulf coasts of Florida, with the bulk of the nesting occurring on
the Atlantic coast of Florida.
3.4.1.1 Pacific Ocean
In the Pacific Ocean, major loggerhead nesting grounds are generally located in temperate and
subtropical regions with scattered nesting in the tropics. Within the Pacific Ocean, loggerhead
sea turtles are represented by a northwestern Pacific nesting aggregation (located in Japan) and a
smaller southwestern nesting aggregation that occurs in eastern Australia (Great Barrier Reef and
Queensland) and New Caledonia (NMFS SEFSC 2001). There are no reported loggerhead
nesting sites in the eastern or central Pacific Ocean basin. Data from 1995 estimated the
Japanese nesting aggregation at 1,000 female loggerhead turtles (Bolten et al. 1996). However,
loggerhead nesting populations in Japan have declined 50-90% in the last 50 years (N. Kamezaki,
Sea Turtle Association of Japan, personal communication, August, 2001). Recent genetic
analyses on female loggerheads nesting in Japan suggest that this “subpopulation” is comprised
of genetically distinct nesting colonies (Hatase et al., 2002) with precise natal homing of
individual females. As a result, Hatase et al. (2002) indicate that loss of one of these colonies
would decrease the genetic diversity of Japanese loggerheads; recolonization of the site would
not be expected on an ecological time scale. In Australia, long-term census data has been
collected at some rookeries since the late 1960s and early 1970s, and nearly all the data show
marked declines in nesting populations since the mid-1980s (Limpus and Limpus, 2003). The
nesting aggregation in Queensland, Australia, was as low as 300 females in 1997.
Pacific loggerhead turtles are captured, injured, or killed in numerous Pacific fisheries including
Japanese longline fisheries in the western Pacific Ocean and South China Seas; direct harvest and
commercial fisheries off Baja California, Mexico; commercial and artisanal swordfish fisheries
off Chile, Columbia, Ecuador, and Peru; purse seine fisheries for tuna in the eastern tropical
Pacific Ocean; and California/Oregon drift gillnet fisheries. In addition, the abundance of
3-5

loggerhead turtles on nesting colonies throughout the Pacific basin has declined dramatically
over the past 10 to 20 years. Loggerhead turtle colonies in the western Pacific Ocean have been
reduced to a fraction of their former abundance by the combined effects of human activities that
have reduced the number of nesting females and reduced the reproductive success of females that
manage to nest (e.g., due to egg poaching).
3.4.1.2 Atlantic Ocean
In the western Atlantic, most loggerhead sea turtles nest from North Carolina to Florida and
along the Gulf coast of Florida. There are at least five western Atlantic subpopulations, divided
geographically as follows: (1) a northern nesting subpopulation, occurring from North Carolina
to northeast Florida at about 29o N; (2) a south Florida nesting subpopulation, occurring from
29oN on the east coast to Sarasota on the west coast; (3) a Florida Panhandle nesting
subpopulation, occurring at Eglin Air Force Base and the beaches near Panama City, Florida; (4)
a Yucatán nesting subpopulation, occurring on the eastern Yucatán Peninsula, Mexico (Márquez
1990 and TEWG 2000); and (5) a Dry Tortugas nesting subpopulation, occurring in the islands
of the Dry Tortugas, near Key West, Florida (NMFS SEFSC 2001). The fidelity of nesting
females to their nesting beach is the reason these subpopulations can be differentiated from one
another. This nest beach fidelity will make recolonization of nesting beaches with sea turtles
from other subpopulations unlikely.
Life history and Distribution
Past literature gave an estimated age at maturity of 21-35 years (Frazer and Ehrhart 1985, Frazer
et al. 1994) with the benthic immature stage lasting at least 10-25 years. However, based on new
data from tag returns, strandings, and nesting surveys NMFS SEFSC (2001) estimated ages of
maturity ranging from 20-38 years and benthic immature stage lasting from 14-32 years.
Mating takes place in late March-early June, and eggs are laid throughout the summer, with a
mean clutch size of 100-126 eggs in the southeastern United States. Individual females nest
multiple times during a nesting season, with a mean of 4.1 nests/individual (Murphy and Hopkins
1984). Nesting migrations for an individual female loggerhead are usually on an interval of 2-3
years, but can vary from 1-7 years (Dodd 1988). Generally, loggerhead sea turtles originating
from the western Atlantic nesting aggregations are believed to lead a pelagic existence in the
North Atlantic Gyre for as long as 7-12 years or more. Stranding records indicate that when
pelagic immature loggerheads reach 40-60 cm straight-line carapace length they begin to live in
coastal inshore and nearshore waters of the continental shelf throughout the U. S. Atlantic and
Gulf of Mexico, although some loggerheads may move back and forth between the pelagic and
benthic environment (Witzell 2002). Benthic immature loggerheads (sea turtles that have come
back to inshore and nearshore waters), the life stage following the pelagic immature stage, have
been found from Cape Cod, Massachusetts, to southern Texas, and occasionally strand on
beaches in Northeastern Mexico. Tagging studies have shown loggerheads which have entered
the benthic environment undertake routine migrations along the coast that are limited by seasonal
water temperatures. Within the action area of this consultation, loggerhead sea turtles occur year
3-6

round in offshore waters off of North Carolina where water temperature is influenced by the Gulf
Stream. As coastal water temperatures warm in the spring, loggerheads begin to immigrate to
North Carolina inshore waters (e.g., Pamlico and Core Sounds) and also move up the coast
(Epperly et al. 1995c; Epperly et al. 1995 a; Epperly et al. 1995b), occurring in Virginia foraging
areas as early as April and on the most northern foraging grounds in the Gulf of Maine in June.
The trend is reversed in the fall as water temperatures cool. The large majority leave the Gulf of
Maine by mid-September but some may remain in Mid-Atlantic and Northeast areas until late
Fall. By December loggerheads have emigrated from inshore North Carolina waters and coastal
waters to the north to waters offshore of North Carolina, particularly off of Cape Hatteras, and
waters further south where the influence of the Gulf Stream provides temperatures favorable to
sea turtles ($ 11° C) (Epperly et al. 1995c; Epperly et al. 1995a; Epperly et al. 1995b).
Loggerhead sea turtles are year-round residents of central and south Florida.
Pelagic and benthic juveniles are omnivorous and forage on crabs, mollusks, jellyfish, and
vegetation at or near the surface (Dodd 1988). Sub-adult and adult loggerheads are primarily
coastal and typically prey on benthic invertebrates such as mollusks and decapod crustaceans in
hard bottom habitats.
Population Dynamics and Status
A number of stock assessments (TEWG 1998, TEWG 2000, NMFS SEFSC 2001, Heppell et al.
2003) have examined the stock status of loggerheads in the waters of the United States, but have
been unable to develop any reliable estimates of absolute population size. Based on nesting data
of the five western Atlantic subpopulations, the south Florida-nesting and the northern-nesting
subpopulations are the most abundant (TEWG 2000 and NMFS SEFSC 2001). Between 1989
and 1998, the total number of nests laid along the U.S. Atlantic and Gulf coasts ranged from
53,014 to 92,182, annually with a mean of 73,751 (TEWG 2000). On average, 90.7% of these
nests were of the south Florida subpopulation and 8.5% were from the northern subpopulation
(TEWG 2000). The Turtle Expert Working Group’s (TEWG) (2000) assessment of the status of
these two better-studied populations concluded that the south Florida subpopulation is
increasing, while no trend is evident (maybe stable but possibly declining) for the northern
subpopulation. However, more recent analysis, including nesting data through 2003, indicate
that there is no discernable trend in the south Florida nesting subpopulation (Florida Fish and
Wildlife Conservation Commission, Florida Marine Research Institute, Statewide and Index
Nesting Beach Survey Programs). Another consideration that may add to the importance and
vulnerability of the northern subpopulation is the sex ratios of this subpopulation. NOAA
Fisheries’ scientists have estimated that the northern subpopulation produces 65 percent males
(NMFS SEFSC 2001). However, new research conducted over a limited time-frame has found
sex ratios opposite to this (Wyneken et al. 2004), and so further information is needed to clarify
the issue. Since nesting female loggerhead sea turtles exhibit nest fidelity, the continued
existence of the northern subpopulation is related to the number of female hatchlings that are
produced. Producing fewer females will limit the number of subsequent offspring produced by
the subpopulation.

3-7

The remaining three subpopulations (the Dry Tortugas, Florida Panhandle, and Yucatán) are
much smaller subpopulations but no less relevant to the continued existence of the species.
Nesting surveys for the Dry Tortugas subpopulation are conducted as part of Florida’s statewide
survey program. Survey effort has been relatively stable during the 9-year period from 19952003 (although the 2002 year was missed). Nest counts ranged from 168-270 but with no
detectable trend during this period (Florida Fish and Wildlife Conservation Commission, Florida
Marine Research Institute, Statewide Nesting Beach Survey Data). Nest counts for the Florida
Panhandle subpopulation are focused on index beaches rather than all beaches where nesting
occurs. Currently, there is not enough information to detect a trend for the subpopulation
(Florida Fish and Wildlife Conservation Commission, Florida Marine Research Institute, Index
Nesting Beach Survey Database). Similarly, nesting survey effort has been inconsistent among
the Yucatán nesting beaches and no trend can be determined for this subpopulation. However,
there is some optimistic news. Zurita et al. (2003) found a statistically significant increase in the
number of nests on seven of the beaches on Quintana Roo, Mexico from 1987-2001 where
survey effort was consistent during the period.
Threats
The diversity of a sea turtle’s life history leaves them susceptible to many natural and human
impacts, including impacts while they are on land, in the benthic environment, and in the pelagic
environment. Hurricanes are particularly destructive to sea turtle nests. Sand accretion and
rainfall that result from these storms as well as wave action can appreciably reduce hatchling
success. For example, in 1992, all of the eggs over a 90-mile length of coastal Florida were
destroyed by storm surges on beaches that were closest to the eye of Hurricane Andrew (Milton
et al. 1994). Other sources of natural mortality include cold stunning and biotoxin exposure.
Anthropogenic factors that impact hatchlings and adult female turtles on land, or the success of
nesting and hatching include: beach erosion, beach armoring and nourishment; artificial lighting;
beach cleaning; increased human presence; recreational beach equipment; beach driving; coastal
construction and fishing piers; exotic dune and beach vegetation; and poaching. An increased
human presence at some nesting beaches or close to nesting beaches has led to secondary threats
such as the introduction of exotic fire ants, feral hogs, dogs and an increased presence of native
species (e.g., raccoons, armadillos, and opossums) which raid and feed on turtle eggs. Although
sea turtle nesting beaches are protected along large expanses of the northwest Atlantic coast (in
areas like Merritt Island, Archie Carr, and Hobe Sound National Wildlife Refuges), other areas
along these coasts have limited or no protection. Sea turtle nesting and hatching success on
unprotected high density east Florida nesting beaches from Indian River to Broward County are
affected by all of the above threats.
Loggerhead sea turtles are affected by a completely different set of anthropogenic threats in the
marine environment. These include oil and gas exploration; coastal development, and
transportation; marine pollution; underwater explosions; hopper dredging, offshore artificial
lighting; power plant entrainment and/or impingement; entanglement in debris; ingestion of
marine debris; marina and dock construction and operation; boat collisions; poaching; and
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fishery interactions. In the pelagic environment loggerheads are exposed to a series of longline
fisheries that include the HMS pelagic longline fisheries, an Azorean longline fleet, a Spanish
longline fleet, and various fleets in the Mediterranean Sea (Aguilar et al. 1995; Bolten et al.
1994; Crouse 1999b). In the benthic environment in waters off the coastal U.S., loggerheads are
exposed to a suite of fisheries in federal and state waters including trawl, purse seine, hook and
line, gillnet, pound net, longline, and trap fisheries (see further discussion in the Environmental
Baseline of this opinion).
3.4.1.3 Summary of Status for Loggerhead Sea Turtles
In the Pacific Ocean, loggerhead turtles are represented by a northwestern Pacific nesting
aggregation (located in Japan) and a smaller southwestern nesting aggregation that occurs in
Australia (Great Barrier Reef and Queensland) and New Caledonia. The abundance of
loggerhead turtles on nesting colonies throughout the Pacific basin have declined dramatically
over the past 10 to 20 years. Data from 1995 estimated the Japanese nesting aggregation at 1,000
female loggerhead turtles (Bolten et al. 1996), but it has probably declined since 1995 and
continues to decline (Tillman 2000). The nesting aggregation in Queensland, Australia, was as
low as 300 females in 1997.
In the Atlantic Ocean, absolute population size is not known, but based on nesting information,
loggerheads are likely much more numerous than in the Pacific Ocean. NOAA Fisheries
recognizes five subpopulations of loggerhead sea turtles in the western north Atlantic based on
genetic studies. Cohorts from all of these are known to occur within the action area of this
consultation. There are no detectable nesting trends for the two largest western Atlantic
subpopulations: the South Florida subpopulation and the northern subpopulation. Because of its
size, the South Florida subpopulation may be critical to the survival of the species in the Atlantic
Ocean. In the past, this nesting aggregation was considered second in size only to the nesting
aggregation on islands in the Arabian Sea off Oman (Ross 1979, Ehrhart 1989, NMFS and
USFWS 1991b). However, the status of the Oman colony has not been evaluated recently and it
is located in an area of the world where it is highly vulnerable to disruptive events such as
political upheavals, wars, catastrophic oil spills, and lack of strong protections for sea turtles
(Meylan et al. 1995). Given the lack of updated information on this population, the status of
loggerheads in the Indian Ocean basin overall is essentially unknown.
All loggerhead subpopulations are faced with a multitude of natural and anthropogenic effects
that negatively influence the status of the species. Many anthropogenic effects occur as a result
of activities outside of U.S. jurisdiction (i.e., fisheries in international waters).
3.4.2

Green Sea Turtle

Federal listing of the green sea turtle occurred on July 28, 1978, with all populations listed as
threatened except for the Florida and Pacific coast of Mexico breeding populations, which are
endangered. The complete nesting range of the green sea turtle is located within NOAA
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Fisheries’ Southeast Region and includes sandy beaches of mainland shores, barrier islands, coral
islands, and volcanic islands between Texas and North Carolina and the U. S. Virgin Islands
(U.S.V.I.) and Puerto Rico (NMFS and USFWS 1991a). Principal U. S. nesting areas for green
sea turtles are in eastern Florida, predominantly Brevard through Broward counties (Ehrhart and
Witherington 1992). Green sea turtle nesting also occurs regularly on St. Croix, U.S.V.I., and on
Vieques, Culebra, Mona, and the main island of Puerto Rico (Mackay and Rebholz 1996).
3.4.2.1 Pacific Ocean
Green turtles are thought to be declining throughout the Pacific Ocean, with the exception of
Hawaii, from a combination of overexploitation and habitat loss (Eckert 1993, Seminoff 2002).
In the western Pacific, the only major (>2,000 nesting females) populations of green turtles occur
in Australia and Malaysia, with smaller colonies throughout the area. Indonesia has a widespread
distribution of green turtles, but has experienced large declines over the past 50 years. The
Hawaii green turtles are genetically distinct and geographically isolated, and the population
appears to be increasing in size despite the prevalence of fibropapilloma and spirochidiasis
(Aguirre et al. 1998 in Balazs and Chaloupka, in press). In the Eastern Pacific, mitochondrial
DNA analysis has indicated that there are three key nesting populations: Michoacan, Mexico;
Galapagos Islands, Ecuador; and Islas Revillagigedos, Mexico (Dutton 2003). There is also
sporadic green turtle nesting along the Pacific coast of Costa Rica.
3.4.2.2 Atlantic Ocean
Life history and Distribution
The estimated age at sexual maturity for green sea turtles is between 20-50 years (Balazs 1982,
Frazer and Ehrhart 1985). Green sea turtle mating occurs in the waters off the nesting beaches.
Each female deposits 1-7 clutches (usually 2-3) during the breeding season at 12-14 day
intervals. Mean clutch size is highly variable among populations, but averages 110-115
eggs/nest. Females usually have 2-4 or more years between breeding seasons, whereas males
may mate every year (Balazs 1983). After hatching, green sea turtles go through a post-hatchling
pelagic stage where they are associated with drift lines of algae and other debris. At
approximately 20 to 25 cm carapace length, juveniles leave pelagic habitats and enter benthic
foraging areas (Bjorndal 1997).
Green sea turtles are primarily herbivorous, feeding on algae and sea grasses, but also
occasionally consume jellyfish and sponges. The post-hatchling, pelagic-stage individuals are
assumed to be omnivorous, but little data are available.
Green sea turtle foraging areas in the southeastern United States include any coastal shallow
waters having macroalgae or sea grasses. This includes areas near mainland coastlines, islands,
reefs, or shelves, and any open-ocean surface waters, especially where advection from wind and
currents concentrates pelagic organisms (Hirth 1997; NMFS and USFWS 1991a). Principal
benthic foraging areas in the southeastern United States include Aransas Bay, Matagorda Bay,
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Laguna Madre, and the Gulf inlets of Texas (Doughty 1984; Hildebrand 1982; Shaver 1994), the
Gulf of Mexico off Florida from Yankeetown to Tarpon Springs (Caldwell and Carr 1957; Carr
1984), Florida Bay and the Florida Keys (Schroeder and Foley 1995), the Indian River Lagoon
System, Florida (Ehrhart 1983), and the Atlantic Ocean off Florida from Brevard through
Broward counties (Wershoven and Wershoven 1992; Guseman and Ehrhart 1992). Adults of
both sexes are presumed to migrate between nesting and foraging habitats along corridors
adjacent to coastlines and reefs.
Population Dynamics and Status
The vast majority of green sea turtle nesting within the southeastern United States occurs in
Florida (Meylan et al. 1995, Johnson and Ehrhart 1994). It is known that current nesting levels
in Florida are reduced compared to historical levels, but the extent of the reduction is not known
(Dodd 1981). However, green sea turtle nesting in Florida has been increasing since 1989
(Florida Fish and Wildlife Conservation Commission, Florida Marine Research Institute Index
Nesting Beach Survey Database). Total nest counts and trends at index beach sites during the
past decade suggest the numbers of green sea turtles that nest within the southeastern United
States are increasing.
Although nesting activity is obviously important in determining population distributions, the
remaining portion of the green turtle’s life is spent on the foraging and breeding grounds. Some
of the principal feeding pastures in the western Atlantic Ocean include the upper west coast of
Florida and the northwestern coast of the Yucatán Peninsula. Additional important foraging
areas in the western Atlantic include the Mosquito and Indian River Lagoon systems and
nearshore wormrock reefs between Sebastian and Ft. Pierce Inlets in Florida, Florida Bay, the
Culebra archipelago and other Puerto Rico coastal waters, the south coast of Cuba, the Mosquito
Coast of Nicaragua, the Caribbean Coast of Panama, and scattered areas along Colombia and
Brazil (Hirth 1971). The summer developmental habitat for green turtles also encompasses
estuarine and coastal waters from North Carolina to as far north as Long Island Sound (Musick
and Limpus 1997).
There are no reliable estimates of the number of immature green sea turtles that inhabit coastal
areas (where they come to forage) of the southeastern United States. However, information on
incidental captures of immature green sea turtles at the St. Lucie Power Plant (they have
averaged 215 green sea turtle captures per year since 1977) in St. Lucie County, Florida (on the
Atlantic coast of Florida) show that the annual number of immature green sea turtles captured has
increased significantly in the past 26 years (FPL 2002).
It is likely that immature green sea turtles foraging in the southeastern United States come from
multiple genetic stocks; therefore, the status of immature green sea turtles in the southeastern
United States might also be assessed from trends at all of the main regional nesting beaches,
principally Florida, Yucatán, and Tortuguero. Trends at Florida beaches were previously
discussed. Trends in nesting at Yucatán beaches cannot be assessed because of a lack of
consistent beach surveys over time. Trends at Tortuguero (ca. 20,000-50,000 nests/year) showed
3-11

a significant increase in nesting during the period 1971-1996 (Bjorndal et al. 1999), and more
recent information continues to show increasing nest counts (Schroeder pers. comm.). Therefore,
it seems reasonable that there is an increase in immature green sea turtles inhabiting coastal areas
of the southeastern United States; however, the magnitude of this increase is unknown.
Threats
The principal cause of past declines and extirpations of green sea turtle assemblages has been the
over-exploitation of green sea turtles for food and other products. Although intentional take of
green sea turtles and their eggs is not extensive within the southeastern United States, green sea
turtles that nest and forage in the region may spend large portions of their life history outside the
region and outside U. S. jurisdiction, where exploitation is still a threat. However, there are still
significant and ongoing threats to green sea turtles from human-related causes in the United
States. These threats include beach armoring, erosion control, artificial lighting, beach
disturbance (e.g., driving on the beach), pollution, foraging habitat loss as a result of direct
destruction by dredging, siltation, boat damage, other human activities, and interactions with
fishing gear. Sea sampling coverage in the pelagic driftnet, pelagic longline, southeast shrimp
trawl, and summer flounder bottom trawl fisheries has recorded takes of green turtles. There is
also the increasing threat from green sea turtle fibropapillomatosis disease. Presently, this
disease is cosmopolitan and has been found to affect large numbers of animals in some areas,
including Hawaii and Florida (Herbst 1994, Jacobson 1990, Jacobson et al. 1991).
3.4.2.3 Summary of Status for Atlantic Green Sea Turtles
Green turtles range in the western Atlantic from Massachusetts to Argentina, including the Gulf
of Mexico and Caribbean, but are considered rare in benthic areas north of Cape Hatteras
(Wynne and Schwartz 1999). Green turtles face many of the same natural and anthropogenic
threats as for loggerhead sea turtles described above. In addition, green turtles are also
susceptible to fibropapillomatosis which can result in death. In the continental United States,
green turtle nesting occurs on the Atlantic coast of Florida (Ehrhart 1979). Recent population
estimates for the western Atlantic area are not available. However, the pattern of green turtle
nesting shows biennial peaks in abundance, with a generally positive trend during the ten years of
regular monitoring since establishment of index beaches in 1989. However, given the species’
late sexual maturity, caution is warranted about over interpreting nesting trend data collected for
less than 15 years.
3.4.3

Kemp’s Ridley Sea Turtle

The Kemp’s ridley was listed as endangered on December 2, 1970. Internationally, the Kemp’s
ridley is considered the most endangered sea turtle (Zwinenberg 1977; Groombridge 1982;
TEWG 2000). Kemp’s ridleys nest primarily at Rancho Nuevo, a stretch of beach in Mexico,
Tamaulipas State. The species occurs mainly in coastal areas of the Gulf of Mexico and the
northwestern Atlantic Ocean. Occasional individuals reach European waters (Brongersma 1972).
Adults of this species are usually confined to the Gulf of Mexico, although adult-sized
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individuals sometimes are found on the east coast of the United States. This species occurs only
in the Atlantic Ocean.
Life history and Distribution
The TEWG (1998) estimates age at maturity from 7-15 years. Females return to their nesting
beach about every 2 years (TEWG 1998). Nesting occurs from April into July and is essentially
limited to the beaches of the western Gulf of Mexico, near Rancho Nuevo in southern
Tamaulipas, Mexico. The mean clutch size for Kemp’s ridleys is 100 eggs/nest, with an average
of 2.5 nests/female/season.
Little is known of the movements of the post-hatching stage (pelagic stage) within the Gulf.
Studies have shown the post-hatchling pelagic stage varies from 1-4 or more years, and the
benthic immature stage lasts 7-9 years (Schmid and Witzell 1997). Benthic immature Kemp’s
ridleys have been found along the east coast seaboard of the United States and in the Gulf of
Mexico. Atlantic benthic immature sea turtles travel northward as the water warms to feed in the
productive, coastal waters off Georgia through New England, returning southward with the onset
of winter (Lutcavage and Musick 1985, Henwood and Ogren 1987, Ogren 1989). Studies
suggest that benthic immature Kemp's ridleys stay in shallow, warm, nearshore waters in the
northern Gulf of Mexico until cooling waters force them offshore or south along the Florida coast
(Renaud 1995).
Stomach contents of Kemp's ridleys along the lower Texas coast consisted of nearshore crabs and
mollusks, as well as fish, shrimp, and other foods considered to be shrimp fishery discards
(Shaver 1991). Pelagic stage Kemp’s ridleys presumably feed on the available sargassum and
associated infauna or other epipelagic species found in the Gulf of Mexico.
Population Dynamics and Status
Of the seven extant species of sea turtles in the world, the Kemp's ridley has declined to the
lowest population level. Most of the population of adult females nest on the Rancho Nuevo
beaches (Pritchard 1969). When nesting aggregations at Rancho Nuevo were discovered in
1947, adult female populations were estimated to be in excess of 40,000 individuals (Hildebrand
1963). By the mid-1980s nesting numbers were below 1,000 (with a low of 702 nests in 1985).
However, observations of increased nesting (with 6,277 nests recorded in 2000) suggest that the
decline in the ridley population has stopped and the population is now increasing (USFWS
2000).
A period of steady increase in benthic immature ridleys has been occurring since 1990 and
appears to be due to increased hatchling production and an apparent increase in survival rates of
immature sea turtles beginning in 1990. The increased survivorship of immature sea turtles is
attributable, in part, to the introduction of turtle excluder devices (TEDs) in the United States and
Mexican shrimping fleets. As demonstrated by nesting increases at the main nesting sites in
Mexico, adult ridley numbers have increased over the last decade. The population model used by

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TEWG (2000) projected that Kemp’s ridleys could reach the Recovery Plan’s intermediate
recovery goal of 10,000 nesters by the year 2015.
Next to loggerheads, Kemp’s ridleys are the second most abundant sea turtle in Virginia and
Maryland waters, arriving in these areas during May and June (Keinath et al. 1987; Musick and
Limpus 1997). The juvenile population of Kemp’s ridley sea turtles in Chesapeake Bay is
estimated to be 211 to 1,083 turtles (Musick and Limpus 1997). These juveniles frequently
forage in submerged aquatic grass beds for crabs (Musick and Limpus 1997). Kemp’s ridleys
consume a variety of crab species, including Callinectes spp., Ovalipes spp., Libinia sp., and
Cancer spp. Mollusks, shrimp, and fish are consumed less frequently (Bjorndal 1997). Upon
leaving Chesapeake Bay in autumn, juvenile ridleys migrate down the coast, passing Cape
Hatteras in December and January (Musick and Limpus 1997). These larger juveniles are joined
there by juveniles of the same size from North Carolina sounds and smaller juveniles from New
York and New England to form one of the densest concentrations of Kemp’s ridleys outside of
the Gulf of Mexico (Musick and Limpus 1997; Epperly et al. 1995a; Epperly et al. 1995b).
Threats
Kemp’s ridleys face many of the same natural threats as loggerheads, including destruction of
nesting habitat from storm events, natural predators at sea, and oceanic events such as coldstunning. Although cold-stunning can occur throughout the range of the species, it may be a
greater risk for sea turtles that utilize the more northern habitats of Cape Cod Bay and Long
Island Sound. For example, in the winter of 1999/2000, there was a major cold-stunning event
where 218 Kemp’s ridleys, 54 loggerheads, and 5 green turtles were found on Cape Cod beaches
(R. Prescott, pers. comm.). Annual cold-stun events do not always occur at this magnitude; the
extent of episodic major cold stun events may be associated with numbers of turtles utilizing
Northeast waters in a given year, oceanographic conditions and the occurrence of storm events in
the late fall. Although many cold-stun turtles can survive if found early enough, cold-stunning
events can represent a significant cause of natural mortality.
Although changes in the use of shrimp trawls and other trawl gear have helped to reduce
mortality of Kemp’s ridleys, this species is also affected by other sources of anthropogenic
impacts similar to those discussed above. For example, in the spring of 2000, a total of five
Kemp’s ridley carcasses were recovered from the same North Carolina beaches where 275
loggerhead carcasses were found. Cause of death for most of the turtles recovered was unknown,
but the mass mortality event was suspected to have been from a large-mesh gillnet fishery
operating offshore in the preceding weeks. The five ridley carcasses that were found are likely to
have been only a minimum count of the number of Kemp’s ridleys that were killed or seriously
injured as a result of the fishery interaction since it is unlikely that all of the carcasses washed
ashore.
Summary of Kemp’s ridley Status
The only major nesting site for ridleys is a single stretch of beach near Rancho Nuevo,
Tamaulipas, Mexico (Carr 1963). The number of nests observed at Rancho Nuevo and nearby
3-14

beaches increased at a mean rate of 11.3% per year from 1985 to 1999. Current totals exceed
3,000 nests per year (TEWG 2000). Kemp’s ridleys mature at an earlier age (7 - 15 years) than
other chelonids, thus ‘lag effects’ as a result of unknown impacts to the non-breeding life stages
would likely have been seen in the increasing nest trend beginning in 1985 (USFWS and NMFS
1992).
The largest contributors to the decline of Kemp’s ridleys in the past were commercial and local
exploitation, especially poaching of nests at the Rancho Nuevo site, as well as the Gulf of
Mexico trawl fisheries. The advent of TED regulations for trawlers and protections for the
nesting beaches have allowed the species to begin to rebound. Many threats to the future of the
species remain, including interactions with fishery gear, marine pollution, foraging habitat
destruction, illegal poaching of nests and potential threats to the nesting beaches from such
sources as global climate change, development, and tourism pressures.
3.4.4

Leatherback Sea Turtle

The leatherback sea turtle was listed as endangered throughout its global range on June 2, 1970.
Leatherbacks are widely distributed throughout the oceans of the world, and are found in waters
of the Atlantic, Pacific, and Indian oceans; the Caribbean Sea; and the Gulf of Mexico (Ernst and
Barbour 1972). Leatherback sea turtles are the largest living turtles and range farther than any
other sea turtle species. Their large size and their tolerance of relatively low temperatures allows
them to occur in northern waters such as off Labrador and in the Barents Sea (NMFS and
USFWS 1995). Adult leatherbacks forage in temperate and subpolar regions from 71/N to 47/S
latitude in all oceans and undergo extensive migrations to and from their tropical nesting
beaches. In 1980, the leatherback population was estimated at approximately 115,000 adult
females globally (Pritchard 1982). That number, however, is probably an overestimation as it
was based on a particularly good nesting year in 1980 (Pritchard 1996). By 1995, this global
population of adult females had declined to 34,500 (Spotila et al. 1996). Pritchard (1996) also
called into question the population estimates from Spotila et al. (1996), and felt it may be
somewhat low, because it ended the modeling on data from a particularly bad nesting year (1994)
while excluding nesting data from 1995, which was a good nesting year. However, at this time,
Spotila et al. (1996) represents the best overall estimate of adult female leatherback population
size.
3.4.4.1 Pacific Ocean.
Based on published estimates of nesting female abundance, leatherback populations have
collapsed or have been declining at all major Pacific basin nesting beaches for the last two
decades (Spotila et al. 1996; NMFS and USFWS 1998c; Sarti et al. 2000; Spotila et al. 2000).
For example, the nesting assemblage on Terengganu, Malaysia – which was one of the most
significant nesting sites in the western Pacific Ocean – has declined severely from an estimated
3,103 females in 1968 to 2 nesting females in 1994 (Chan and Liew 1996). Nesting assemblages
of leatherback turtles are in decline along the coasts of the Solomon Islands; a historically
3-15

important nesting area (D. Broderick, pers. comm., in Dutton et al. 1999). In Fiji, Thailand,
Australia, and Papua New Guinea (East Papua), leatherback turtles have only been known to nest
in low densities and scattered colonies.
Only an Indonesian nesting assemblage has remained relatively abundant in the Pacific basin.
The largest extant leatherback nesting assemblage in the Indo-Pacific lies on the north Vogelkop
coast of Irian Jaya (West Papua), Indonesia, with over 3,000 nests recorded annually
(Putrawidjaja 2000; Suarez et al. 2000). During the early-to-mid 1980s, the number of female
leatherback turtles nesting on the two primary beaches of Irian Jaya appeared to be stable. More
recently, this population has come under increasing threats that could cause this population to
experience a collapse that is similar to what occurred at Terengganu, Malaysia. In 1999, for
example, local Indonesian villagers started reporting dramatic declines in sea turtle populations
near their villages (Suarez 1999). Unless hatchling and adult turtles on nesting beaches receive
more protection, this population will continue to decline. Declines in nesting assemblages of
leatherback turtles have been reported throughout the western Pacific region, with nesting
assemblages well below abundance levels observed several decades ago (e.g., Suarez 1999).
In the western Pacific Ocean and South China Seas, leatherback turtles are captured, injured, or
killed in numerous fisheries, including Japanese longline fisheries. Leatherback turtles in the
western Pacific are also threatened by poaching of eggs, killing of nesting females, human
encroachment on nesting beaches, beach erosion, and egg predation by animals.
In the eastern Pacific Ocean, nesting populations of leatherback turtles are declining along the
Pacific coast of Mexico and Costa Rica. According to reports from the late 1970s and early
1980s, three beaches on the Pacific coast of Mexico supported as many as half of all leatherback
turtle nests for the eastern Pacific. Since the early 1980s, the eastern Pacific Mexican population
of adult female leatherback turtles has declined to slightly more than 200 individuals during
1998-99 and 1999-2000 (Sarti et al. 2000). Spotila et al. (2000) reported the decline of the
leatherback turtle population at Playa Grande, Costa Rica, which had been the fourth largest
nesting colony in the world. Between 1988 and 1999, the nesting colony declined from 1,367 to
117 female leatherback turtles. Based on their models, Spotila et al. (2000) estimated that the
colony could fall to less than 50 females by 2003-2004. Leatherback turtles in the eastern Pacific
Ocean are captured, injured, or killed in commercial and artisanal swordfish fisheries off Chile,
Columbia, Ecuador, and Peru; purse seine fisheries for tuna in the eastern tropical Pacific Ocean;
and California/Oregon drift gillnet fisheries. Because of the limited data, we cannot provide
high-certainty estimates of the number of leatherback turtles captured, injured, or killed through
interactions with these fisheries. However, between 8 and 17 leatherback turtles were estimated
to have died annually between 1990 and 2000 in interactions with the California/Oregon drift
gillnet fishery; 500 leatherback turtles are estimated to die annually in Chilean and Peruvian
fisheries; 200 leatherback turtles are estimated to die in direct harvests in Indonesia; and before
1992, the North Pacific driftnet fisheries for squid, tuna, and billfish captured an estimated 1,000
leatherback turtles each year, killing about 111 of them each year.

3-16

Although all causes of the declines in leatherback turtle colonies in the eastern Pacific have not
been documented, Sarti et al. (1998) suggest that the declines result from egg poaching, adult and
sub-adult mortalities incidental to high seas fisheries, and natural fluctuations due to changing
environmental conditions. Some published reports support this suggestion. Sarti et al. (2000)
reported that female leatherback turtles have been killed for meat on nesting beaches like Píedra
de Tiacoyunque, Guerrero, Mexico. Eckert (1997) reported that swordfish gillnet fisheries in
Peru and Chile contributed to the decline of leatherback turtles in the eastern Pacific. The
decline in the nesting population at Mexiquillo, Mexico occurred at the same time that effort
doubled in the Chilean driftnet fishery. In response to these effects, the eastern Pacific
population has continued to decline, leading some researchers to conclude that the leatherback is
on the verge of extinction in the Pacific Ocean (e.g., Spotila et al. 1996; Spotila et al. 2000).
NOAA Fisheries’ assessment of three nesting aggregations in its February 23, 2004, opinion
supports this conclusion: if no action is taken to reverse their decline, leatherback sea turtles
nesting in the Pacific Ocean either have high risks of extinction in a single human generation (for
example, nesting aggregations at Terrenganu and Costa Rica) or they have a high risk of
declining to levels where more precipitous declines become almost certain (for example Irian
Jaya) (NOAA Fisheries 2004).
3.4.4.2 Atlantic Ocean.
In the Atlantic Ocean, leatherbacks have been recorded as far north as Newfoundland, Canada,
and Norway, and as far south as Uruguay, Argentina, and South Africa (NMFS SEFSC 2001).
Female leatherbacks nest from the southeastern United States to southern Brazil in the western
Atlantic and from Mauritania to Angola in the eastern Atlantic. The most significant nesting
beaches in the Atlantic, and perhaps in the world, are in French Guiana and Suriname (NMFS
SEFSC 2001). Genetic analyses of leatherbacks to date indicate that within the Atlantic basin
there are genetically different nesting populations; the St. Croix nesting population (U.S. Virgin
Islands), the mainland nesting Caribbean population (Florida, Costa Rica, Suriname/French
Guiana) and the Trinidad nesting population (Dutton et al. 1999). When the hatchlings leave the
nesting beaches, they move offshore but eventually utilize both coastal and pelagic waters. Very
little is known about the pelagic habits of the hatchlings and juveniles, and they have not been
documented to be associated with the sargassum areas as are other species. Leatherbacks are
deep divers, with recorded dives to depths in excess of 1,000 m (Eckert et al. 1989; Hayes et al.
2004).
Life History and Distribution
Leatherbacks are a long-lived species, living for over 30 years. They reach sexual maturity
somewhat faster than other sea turtles(except Kemp’s ridley), with an estimated range from 3-6
years (Rhodin 1985) to 13-14 years (Zug and Parham 1996). They nest frequently (up to10 nests
per year) during a nesting season and nest about every 2-3 years. During each nesting, they
produce 100 eggs or more in each clutch and, thus, can produce 700 eggs or more per nesting
season (Schultz 1975). However, a significant portion (up to approximately 30%) of the eggs
can be infertile. Thus, the actual proportion of eggs that can result in hatchlings is less than this
3-17

seasonal estimate. The eggs will incubate for 55-75 days before hatching. Based on a review of
all sightings of leatherback sea turtles of <145 cm curved carapace length (ccl), Eckert (1999)
found that leatherback juveniles remain in waters warmer than 26°C until they exceed 100 cm
ccl.
Leatherbacks are the most pelagic of the sea turtles, but enter coastal waters on a seasonal basis
to feed in areas where jellyfish are concentrated. Leatherback sea turtles feed primarily on
cnidarians (medusae, siphonophores) and tunicates.
Evidence from tag returns and strandings in the western Atlantic suggests that adult leatherback
sea turtles engage in routine migrations between boreal, temperate and tropical waters (NMFS
and USFWS 1992). A 1979 aerial survey of the outer Continental Shelf from Cape Hatteras,
North Carolina to Cape Sable, Nova Scotia showed leatherbacks to be present throughout the
area with the most numerous sightings made from the Gulf of Maine south to Long Island.
Leatherbacks were sighted in waters where depths ranged from 1-4151 m, but 84.4% of sightings
were in areas where the water was less than 180 m deep (Shoop and Kenney 1992).
Leatherbacks were sighted in waters of a similar sea surface temperature as loggerheads; from 727.2 ° C (Shoop and Kenney 1992). However, this species appears to have a greater tolerance for
colder waters because more leatherbacks were found at the lower temperatures (Shoop and
Kenney 1992). This aerial survey estimated the in-water leatherback population from near Nova
Scotia, Canada to Cape Hatteras, North Carolina at approximately 300-600 animals.
Population Dynamics and Status
The status of the Atlantic leatherback population is less clear than the Pacific population. The
total Atlantic population size is undoubtedly larger than in the Pacific, but overall population
trends are unclear. In 1996, the entire western Atlantic population was characterized as stable at
best (Spotila et al. 1996), with numbers of nesting females reported to be on the order of 18,800.
A subsequent analysis by Spotila (pers. comm.) indicated that by 2000, the western Atlantic
nesting population had decreased to about 15,000 nesting females. According to NMFS SEFSC
(2001) the nesting aggregation in French Guiana has been declining at about 15 percent per year
since 1987. However, from 1979-1986, the number of nests was increasing at about 15 percent
annually which could mean that the current 15 percent decline could be part of a nesting cycle
which coincides with the erosion cycle of Guiana beaches described by Schultz (1975). In
Suriname, leatherback nest numbers have shown large recent increases (with more than 10,000
nests per year since 1999 and a peak of 30,000 nests in 2001), and the long-term trend for the
overall Suriname and French Guiana population may show an increase (Girondot 2002 in
Hilterman and Goverse 2003). The number of nests in Florida and the U.S. Caribbean has been
increasing at about 10.3 percent and 7.5 percent, respectively, per year since the early 1980s but
the magnitude of nesting is much smaller than that along the French Guiana coast (NMFS
SEFSC 2001). Also, because leatherback females can lay 10 nests per season, the recent
increases to 400 nests per year in Florida may only represent as few as 40 individual female
nesters per year.

3-18

In summary, the conflicting information regarding the status of Atlantic leatherbacks makes it
difficult to characterize the current status. Numbers at some nesting sites are increasing, but are
decreasing at other sites. Tag return data emphasize the wide-ranging nature of the leatherback
and the link between South American nesters and animals found in U.S. waters. For example, a
nesting female tagged May 29, 1990, in French Guiana was later recovered and released alive
from the York River, Virginia. Another nester tagged in French Guiana on June 21, 1990, was
later found dead in Palm Beach, Florida (STSSN database). Genetic studies performed within
the NED indicate that the leatherbacks captured in the HMS pelagic longline fishery were
primarily from the French Guiana and Trinidad nesting stocks (over 95%), though individuals
from West African stocks were surprisingly absent (Roden et al. In press).
There are a number of problems contributing to the uncertainty of the leatherback nest counts and
population assessments. The nesting beaches of the Guianas (Guyana, French Guiana, and
Suriname) and Trinidad are by far the most important in the western Atlantic. However, beaches
in this region undergo cycles of erosion and reformation, so that the nesting beaches are not
consistent over time. Additionally, leatherback sea turtles do not exhibit the same degree of nestsite fidelity demonstrated by loggerhead and other hardshell sea turtles, further confounding
analysis of population trends using nesting data. Reported declines in one country and reported
increases in another may be the result of migration and beach changes, not true population
changes. Nesting surveys, as well as being hampered by the inconsistency of the nesting
beaches, are themselves inconsistent throughout the region. Survey effort varies widely in the
seasonal coverage, areal coverage, and actual surveyed sites. Surveys have not been conducted
consistently throughout time, or have even been dropped entirely as the result of wars, political
turmoil, funding vagaries, etc. The methods vary in assessing total numbers of nests and total
numbers of females. Many sea turtle scientists agree that the Guianas (and some would include
Trinidad) should be viewed as one population and that a synoptic evaluation of nesting at all
beaches in the region is necessary to develop a true picture of population status (Reichart 2001).
No such region-wide assessment has been conducted recently. The most recent, complete
estimates of regional leatherback populations are in Spotila et al. (1996). As discussed above,
nesting in the Guianas may have been declining in the late 1990s but may have increased again in
the early 2000s. Spotila et al. estimated that the leatherback population for the Atlantic basin,
including all nesting beaches in the Americas, the Caribbean, and West Africa totaled
approximately 27,600 nesting females, with an estimated range of 20,082-35,133. We believe
that the current population probably still lies within this range, taking into account the reported
nesting declines and increases and the uncertainty surrounding them. We therefore choose to rely
on Spotila et al.’s (1996) published total Atlantic population estimates, rather than attempt to
construct a new population estimate here, based on our interpretation of the various, confusing
nesting reports from areas within the region.
Threats
Zug and Parham (1996) pointed out that the main threat to leatherback populations in the
Atlantic is the combination of fishery-related mortality (especially entanglement in gear and

3-19

drowning in trawls) and the intense egg harvesting on the main nesting beaches. Other important
ongoing threats to the population include pollution, loss of nesting habitat, and boat strikes.
Of the turtle species, leatherbacks seem to be the most vulnerable to entanglement in fishing
gear. This susceptibility may be the result of their body type (large size, long pectoral flippers,
and lack of a hard shell), their attraction to gelatinous organisms and algae that collect on buoys
and buoy lines at or near the surface, possibly their method of locomotion, and perhaps to the
lightsticks used to attract target species in longline fisheries. They are also susceptible to
entanglement in gillnets and pot/trap lines (used in various fisheries) and capture in trawl gear
(e.g., shrimp trawls).
Leatherbacks are exposed to pelagic longline fisheries in many areas of their range. Unlike
loggerhead turtle interactions with longline gear, leatherback turtles do not usually ingest
longline bait. Instead, leatherbacks are foul hooked by longline gear (e.g., on the flipper or
shoulder area) rather than mouth hooked or swallowing the hook. According to observer records,
an estimated 6,363 leatherback sea turtles were caught by the U.S. Atlantic tuna and swordfish
longline fisheries between 1992-1999, of which 88 were released dead (NMFS SEFSC 2001).
The U.S. fleet accounts for only 5-8% of the hooks fished in the Atlantic Ocean, and adding up
the under-represented observed takes of the other 23 countries that actively fish in the area would
lead to annual take estimates of thousands of leatherbacks over different life stages. Basin-wide,
Lewison et al. (2004) estimated that 30,000 - 60,000 leatherback sea turtle captures occurred in
Atlantic pelagic longline fisheries in the year 2000 alone (note that multiple captures of the same
individual are known to occur, so the actual number of individuals captured may not be as high).
Leatherbacks are also susceptible to entanglement in the lines associated with trap/pot gear used
in several fisheries. From 1990-2000, 92 entangled leatherbacks were reported from New York
through Maine (Dwyer et al. 2002). Additional leatherbacks stranded wrapped in line of
unknown origin or with evidence of a past entanglement (Dwyer et al. 2002). Fixed gear
fisheries in the Mid-Atlantic have also contributed to leatherback entanglements. In North
Carolina, two leatherback sea turtles were reported entangled in a crab pot buoy inside Hatteras
Inlet (D. Fletcher, pers. comm. to S. Epperly). A third leatherback was reported entangled in a
crab pot buoy in Pamlico Sound near Ocracoke. This turtle was disentangled and released alive;
however, lacerations on the front flippers from the lines were evident (D. Fletcher, pers. comm.
to S. Epperly). In the Southeast, leatherbacks are vulnerable to entanglement in Florida’s lobster
pot and stone crab fisheries. In the U.S. Virgin Islands, where one of five leatherback strandings
from 1982 to 1997 was due to entanglement (Boulon 2000), leatherbacks have been observed
with their flippers wrapped in the line of West Indian fish traps (R. Boulon, pers. comm. to J.
Braun-McNeill). Because many entanglements of this typically pelagic species likely go
unnoticed, entanglements in fishing gear may be much higher.
Leatherback interactions with the southeast Atlantic shrimp fishery, which operates
predominately from North Carolina through southeast Florida (NOAA Fisheries 2002), have also
been a common occurrence. Leatherbacks, which migrate north annually, are likely to encounter
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shrimp trawls working in the coastal waters off the Atlantic coast from Cape Canaveral, Florida
to the Virginia/North Carolina border. For many years, TEDs that were required for use in the
southeast shrimp fishery were less effective at excluding leatherbacks than the smaller, hardshelled turtle species. To address this problem, on February 21, 2003, NOAA Fisheries issued a
final rule to amend the TED regulations. Modifications to the design of TEDs are now required
in order to exclude leatherbacks and large and sexually mature loggerhead and green turtles.
Other trawl fisheries are also known to interact with leatherback sea turtles. In October 2001, a
Northeast Fisheries Science Center observer documented the take of a leatherback in a bottom
otter trawl fishing for Loligo squid off of Delaware; TEDs are not required in this fishery. The
winter trawl flounder fishery, which did not come under the revised TED regulations, may also
interact with leatherback sea turtles.
Gillnet fisheries operating in the nearshore waters of the Mid-Atlantic states are also suspected of
capturing, injuring, and/or killing leatherbacks when these fisheries and leatherbacks co-occur.
Data collected by the NEFSC Fisheries Observer Program from 1994 through 1998 (excluding
1997) indicate that a total of 37 leatherbacks were incidentally captured (16 lethally) in drift
gillnets set in offshore waters from Maine to Florida during this period. Observer coverage for
this period ranged from 54% to 92%.
Poaching is not known to be a problem for nesting populations in the continental U.S. However,
the NMFS SEFSC (2001) notes that poaching of juveniles and adults is still occurring in the U.S.
Virgin Islands and the Guianas. In all, four of the five strandings in St. Croix were the result of
poaching (Boulon 2000). A few cases of fishermen poaching leatherbacks have been reported
from Puerto Rico, but most of the poaching is on eggs.
Leatherback sea turtles may be more susceptible to marine debris ingestion than other species
due to their pelagic existence and the tendency of floating debris to concentrate in convergence
zones that adults and juveniles use for feeding areas and migratory routes (Lutcavage et al. 1997;
Shoop and Kenney 1992). Investigations of the stomach contents of leatherback sea turtles
revealed that a substantial percentage (44% of the 16 cases examined) contained plastic
(Mrosovsky 1981). Along the coast of Peru, intestinal contents of 19 of 140 (13%) leatherback
carcasses were found to contain plastic bags and film (Fritts 1982). The presence of plastic
debris in the digestive tract suggests that leatherbacks might not be able to distinguish between
prey items and plastic debris (Mrosovsky 1981). Balazs (1985) speculated that the object may
resemble a food item by its shape, color, size or even movement as it drifts about, and induce a
feeding response in leatherbacks.
It is important to note that, like marine debris, fishing gear interactions and poaching are
problems for leatherbacks throughout their range. Entanglements are common in Canadian
waters where Goff and Lien (1988) reported that 14 of 20 leatherbacks encountered off the coast
of Newfoundland/Labrador were entangled in fishing gear including salmon net, herring net,
gillnet, trawl line and crab pot line. Leatherbacks are reported taken by many other nations that
participate in Atlantic pelagic longline fisheries, including Taipei, Brazil, Trinidad, Morocco,
3-21

Cyprus, Venezuela, Korea, Mexico, Cuba, U.K., Bermuda, People’s Republic of China, Grenada,
Canada, Belize, France, and Ireland (see NMFS SEFSC 2001, for a description of take records).
Leatherbacks are known to drown in fish nets set in coastal waters of Sao Tome, West Africa
(Castroviejo et al. 1994; Graff 1995). Gillnets are one of the suspected causes for the decline in
the leatherback sea turtle population in French Guiana (Chevalier et al. 1999), and gillnets
targeting green and hawksbill turtles in the waters of coastal Nicaragua also incidentally catch
leatherback turtles (Lagueux et al. 1998). Observers on shrimp trawlers operating in the
northeastern region of Venezuela documented the capture of six leatherbacks from 13,600 trawls
(Marcano and Alio 2000). An estimated 1,000 mature female leatherback sea turtles are caught
annually in fishing nets off of Trinidad and Tobago with mortality estimated to be between 5095% (Eckert and Lien 1999). However, many of the turtles do not die as a result of drowning,
but rather because the fishermen butcher them in order to get them out of their nets (NMFS
SEFSC 2001).

3.4.4.3 Summary of Leatherback Status
In the Pacific Ocean, the abundance of leatherback turtle nesting individuals and colonies has
declined dramatically over the past 10 to 20 years. Nesting colonies throughout the eastern and
western Pacific Ocean have been reduced to a fraction of their former abundance by the
combined effects of human activities that have reduced the number of nesting females. In
addition, egg poaching has reduced the reproductive success of the remaining nesting females.
At current rates of decline, leatherback turtles in the Pacific basin are a critically endangered
species with a low probability of surviving and recovering in the wild.
In the Atlantic Ocean, our understanding of the status and trends of leatherback turtles is much
more confounded, although the picture does not appear nearly as bleak as in the Pacific. The
number of female leatherbacks reported at some nesting sites in the Atlantic Ocean has increased,
while at others they have decreased. Some of the same factors that led to precipitous declines of
leatherbacks in the Pacific also affect leatherbacks in the Atlantic: leatherbacks are captured and
killed in many kinds of fishing gear and interact with fisheries in state, federal and international
waters. Poaching is a problem and affects leatherbacks that occur in U.S. waters. Leatherbacks
also appear to be more susceptible to death or injury from ingesting marine debris than other
turtle species.
3.4.5

Olive Ridley Sea Turtle

The olive ridley sea turtle was listed on July 28, 1978, with all breeding populations listed as
threatened except for the Pacific coast of Mexico population which is endangered. There have
also been recommendations that the western Atlantic olive ridley populations be reclassified as
endangered (Reichart 1993). The olive ridley is a small, hard-shelled sea turtle with an olivecolored shell. It typically occurs within the tropical regions of the Pacific, Atlantic, and Indian
Oceans. This species does not nest in the United States, but during feeding migrations, olive
3-22

ridley turtles nesting in the Pacific may disperse into waters of the southwestern U.S.,
occasionally as far north as Oregon.
The olive ridley is most noted for its massive nesting aggregations, known as arribadas, with
thousands of females nesting in large simultaneous waves over small stretches of beach.
Arribadas may be precipitated by climatic events, such as a strong offshore wind, or by certain
phases of the moon and tide; however, there is a major element of unpredictability regarding the
trigger and timing at all arribada sites. Although not every adult female participates in these
arribadas, the vast majority do.
3.4.5.1 Pacific Ocean.
In the eastern Pacific, olive ridleys nest primarily on beaches from Mexico south to at least
Colombia (NMFS and USFWS 1995) with major nesting beaches at Escobilla, Mexico; La Flor,
Nicaragua; and Ostional and Nancite, Costa Rica. Declines in nesting have been documented for
Playa Nancite, Costa Rica. However, other nesting populations along the Pacific coast of
Mexico and Costa Rica appear stable or increasing (NMFS 2004). When not at the nesting areas,
adult olive ridleys are generally found in warm waters from Baja California, Mexico to Chile
(Silva-Batiz et al. 1996). In the western Pacific, nesting information is not available for several
countries, but information from Indonesia suggests an increase in nesting, while information
from Malaysia and Thailand suggests that nesting has declined to very low levels in those
countries (NMFS 2004). In the Indian Ocean, olive ridleys nest in great abundance in eastern
India and Sri Lanka, although minor nesting also occurs at other localities. Gahirmatha, located
in the Bhitarkanika Wildlife Sanctuary, India, supports perhaps one of the largest nesting
populations in the world with an average of 398,000 females nesting in a given year. These
populations, however, are suffering high mortality from nearshore gillnets and trawl fisheries.
3.4.5.2 Atlantic Ocean.
A small and declining population of olive ridleys nests in the western Atlantic, primarily along
the coasts of Suriname and French Guiana. The best studied is the relatively large aggregation in
Suriname, but numbers there have decreased dramatically, and there have been recommendations
that the western Atlantic population be reclassified as endangered (Reichart, 1993). As is the
case with olive ridleys in the Pacific, the overall range of the species is much broader than the
nesting range. Sporadic sightings of olive ridleys have occurred in the Caribbean and recently in
Florida, and one confirmed individual was captured on a longline set in the northern Atlantic
Ocean.
Life history and Distribution
Age at sexual maturity for olive ridleys is not known, but if similar to its close relative the
Kemp’s ridley, it would be 7 to 15 years. Olive ridleys typically nest 1 to 3 times per season,
producing about 100 to110 eggs on each occasion. The inter-nesting interval is variable, but for

3-23

most localities it is approximately 14 days for solitary nesters and 28 days for arribada nesters.
Incubation takes about 50 to 60 days.
As described above, there are no known nesting sites for olive ridleys in U.S. waters. In the past
several years, olive ridley turtles have been occasionally documented in stranding records in the
southeastern U.S. and U.S. Caribbean, where they had never been documented before. In
addition, the documented capture of an olive ridley in the NED experiment in 2003 is the first
known interaction with the HMS pelagic longline fishery. Caution should be used to avoid over
interpreting these very few occurrences, but the change from absence to presence in U.S. Atlantic
records is notable.
There are surprisingly few data relating to the feeding habits of the olive ridley. However, those
reports that do exist suggest that the diet in the western Atlantic and eastern Pacific includes
crabs, shrimp, rock lobsters, jellyfish, and tunicates. In some parts of the world, it has been
reported that the principal food is algae.
Population Dynamics and Status
The olive ridley is widely regarded as the most abundant sea turtle in the world because of the
continued existence of several large arribadas. However, since its listing under the ESA, there
has been a decline in abundance of this species in the western Atlantic, probably the result of
continued direct and incidental take, particularly in shrimp trawl nets and nearshore gill nets.
The western North Atlantic (Suriname, French Guiana, and Guyana) nesting population has
declined more than 80 percent since 1967. Similar declines have been seen in the Pacific,
although some nesting populations appear to be stable or increasing as described above. The
Indian Ocean continues to support one of the largest nesting populations in the world. However,
these populations are also known to suffer high anthropogenic mortality from fishery
interactions.
Threats
The decline of this species is primarily due to human activities, including the direct harvest of
adults and eggs, incidental capture in commercial fisheries, and loss of nesting habitat. However,
their characteristic form of nesting, the arribada, also leaves then susceptible to natural predation
(as well as poaching) and a high incidence of incidental nest destruction by other nesting turtles.
Even the close proximity of a rotting nest can lead to bacterial contamination and destruction of
all or part of the surrounding nests (NMFS 2004).
3.4.5.3 Summary of Status for Olive Ridley Sea Turtles
The western North Atlantic (Suriname, French Guiana, and Guyana) nesting population has
declined more than 80 percent since 1967. Anthropogenic impacts similar to those experienced
by other sea turtle species (i.e., such as fishing interactions and poaching) appear to be primarily
responsible for the decline. There are no olive ridley turtle nesting sites within the U.S. In the
past several years, however, olive ridley turtles have been occasionally documented in stranding
3-24

records in the southeastern U.S. and U.S. Caribbean, where they had never been documented
before. In addition, in 2003, the NED experimental longline fishery in the northern western
Atlantic documented capture of an olive ridley sea turtles. Caution should be used to avoid
overinterpreting these very few occurrences, but the change from absence to presence in U.S.
Atlantic records is notable.
3.4.6

Hawksbill Sea Turtle

The hawksbill turtle was listed as endangered under the precursor of the ESA on June 2, 1970,
and is considered Critically Endangered by the International Union for the Conservation of
Nature (IUCN). The hawksbill is a medium-sized sea turtle with adults in the Caribbean ranging
in size from approximately 62.5 to 94.0 cm straight carapace length. The species occurs in all
ocean basins, although it is relatively rare in the Eastern Atlantic and Eastern Pacific, and absent
from the Mediterranean Sea. Hawksbills are the most tropical of the marine turtles, ranging from
approximately 30° N latitude to 30° S latitude. They are closely associated with coral reefs and
other hard-bottom habitats, but they are also found in other habitats including inlets, bays and
coastal lagoons (NMFS and USFWS 1993). There are five regional nesting populations with
more than 1,000 females nesting annually. These populations are in the Seychelles, Mexico,
Indonesia, and two in Australia (Meylan and Donnelly 1999). There has been a global
population decline of over 80% during the last three generations (105 years) (Meylan and
Donnelly 1999).
3.4.6.1 Pacific Ocean.
Anecdotal reports throughout the Pacific indicate that the current population is well below
historical levels (NMFS 2004). It is believed that this species is rapidly approaching extinction
in the Pacific because of harvesting for its meat, shell, and eggs as well as destruction of nesting
habitat (NMFS 2001). Hawksbill sea turtles nest in the Hawaiian Islands as well as the islands
and mainland of southeast Asia, from China to Japan, and throughout the Philippines, Malaysia,
Indonesia, Papua New Guinea, the Solomon Islands, and Australia (NMFS 2004). However,
along the eastern Pacific rim where nesting was common in the 1930's, hawksbill’s are now rare
or absent (Cliffton et al. 1982; NMFS 2004).
3.4.6.2 Atlantic Ocean.
In the Western Atlantic, the largest hawksbill nesting population occurs in the Yucatán Peninsula
of Mexico (Garduño-Andrade et al. 1999). With respect to the U.S., nesting occurs in Puerto
Rico, the U.S. Virgin Islands, and the southeast coast of Florida. Nesting also occurs outside of
the U.S. and its territories in Antigua, Barbados, Costa Rica, Cuba, and Jamaica (Meylan 1999a).
Outside of the nesting areas, hawksbills have been seen off of the U.S. gulf states and along the
eastern seaboard as far north as Massachusetts, although sightings north of Florida are rare
(NMFS 2004).

3-25

Life History and Distribution
The best estimate of age at sexual maturity for hawksbill sea turtles is about 20-40 years
(Chaloupka and Limpus 1997; Crouse 1999a; NMFS 2004). Reproductive females undertake
periodic (usually non-annual) migrations to their natal beach to nest. Movements of reproductive
males are less well known, but are presumed to involve migrations to the nesting beach or to
courtship stations along the migratory corridor (Meylan 1999b). Females nest an average of 3-5
times per season (Meylan and Donnelly 1999, Richardson et al. 1999). Clutch size is larger on
average (up to 250 eggs) than that of other turtles (Hirth 1980). Reproductive females may
exhibit a high degree of fidelity to their nest sites.
The life history of hawksbills consists of a pelagic stage that lasts from the time they leave the
nesting beach as hatchlings until they are approximately 22 - 25 cm in straight carapace length
(Meylan 1988, Meylan and Donnelly 1999), followed by residency in developmental habitats
(foraging areas where immatures reside and grow) in coastal waters. Adult foraging habitat,
which may or may not overlap with developmental habitat, is typically coral reefs, although other
hard-bottom communities and occasionally mangrove-fringed bays may be occupied. Hawksbills
show fidelity to their foraging areas over several years (van Dam and Diez 1998).
The hawksbill’s diet is highly specialized and consists primarily of sponges (Meylan 1988)
although other food items, notably corallimorphs and zooanthids, have been documented to be
important in some areas of the Caribbean (van Dam and Diez 1997, Mayor et al. 1998, Leon and
Diez 2000).
Population Dynamics and Status
Estimates of the annual number of nests at hawksbill sea turtle nesting sites are of the order of
hundreds to a few thousand. Nesting within the southeastern U.S. and U.S. Caribbean is
restricted to Puerto Rico (>650 nests/yr), the U.S. Virgin Islands (~400 nests/yr), and, rarely,
Florida (0-4 nests/yr) (Eckert 1995, Meylan 1999a, Florida Fish and Wildlife Conservation
Commission, Florida Marine Research Institute’s Statewide Nesting Beach Survey data 2002).
At the two principal nesting beaches in the U.S. Caribbean where long-term monitoring has been
carried out, populations appear to be increasing (Mona Island, Puerto Rico) or stable (Buck
Island Reef National Monument, St. Croix, USVI) (Meylan 1999a).
Threats
As described above for other sea turtle species, hawksbill sea turtles are affected by habitat loss,
habitat degradation, fishery interactions, and poaching in some parts of their range. There
continues to be a black market for hawksbill shell products (“tortoiseshell”), which likely
contributes to the harvest of this species.
3.4.6.3 Summary of Status for Hawksbill Sea Turtles
Worldwide, hawksbill sea turtle populations are declining. They face many of the same threats
affecting other sea turtle species. In addition, there continues to be a commercial market for
3-26

hawksbill shell products despite protections afforded to the species under U.S. law and
international conventions.
3.5

Environmental Baseline

This section contains an analysis of the effects of past and ongoing human and natural factors
leading to the current status of the species, their habitat, and the ecosystem, within the action
area. The environmental baseline is a snapshot of the factors affecting the species and includes
federal, state, tribal, local, and private actions already affecting the species, or that will occur
contemporaneously with the consultation in progress. Unrelated, future federal actions affecting
the same species that have completed formal or informal consultation are also part of the
environmental baseline, as are implemented and ongoing federal and other actions within the
action area that may benefit listed species.
3.5.1

Factors Affecting Sea Turtles in the Action Area

The environmental baseline for this opinion includes the effects of several activities that affect
the survival and recovery of threatened and endangered species in the action area. As noted
above, sea turtles found in the action area may travel widely throughout the Atlantic, Gulf of
Mexico, and Caribbean Sea. Therefore, individuals found in the action area can potentially be
affected by activities anywhere within this wide range. The most thorough account of permitted
and non-permitted activities, including research activities that are not harmful to the turtles, in
the entire U.S. Atlantic, Gulf of Mexico, and Caribbean can be found in Appendix 2 of the
NOAA Technical Memorandum NMFS-SEFSC-455, Stock Assessments of Loggerhead and
Leatherback Sea Turtles and an Assessment of the Impact of the Pelagic Longline Fishery on the
Loggerhead and Leatherback Sea Turtles of the Western North Atlantic (NMFS SEFSC 2001).
The most significant activities affecting sea turtles in the Atlantic are fisheries and conservation
activities directed at fisheries. Other environmental impacts to turtles may result from vessel
operations, discharges, dredging, military activities, oil and gas development activities, industrial
cooling water intake, aquaculture, recreational fishing, coastal development, directed take, and
marine debris.
3.5.1.1 Federal Actions
In recent years, NOAA Fisheries has undertaken numerous ESA section 7 consultations to
address the effects of federally-permitted fisheries and other federal actions on threatened and
endangered sea turtle species. Each of those consultations sought to develop ways of reducing
the probability of adverse effects of the action on sea turtles. Similarly, recovery actions NOAA
Fisheries has undertaken under the ESA are addressing the problem of take of sea turtles in the
fishing and shipping industries and other activities such as Army Corps of Engineers (COE)
dredging operations. The summary below of anticipated sources of incidental take of sea turtles

3-27

from federal actions includes only those actions which have already concluded or are currently
undergoing formal section 7 consultation.
Fisheries
Adverse effects on threatened and endangered sea turtles from several types of fishing gear occur
in the action area. Gillnet, longline, trawl gear, and pot fisheries have all been documented as
interacting with sea turtles. For all fisheries for which there is a fishery management plan (FMP)
or for which any federal action is taken to manage that fishery, impacts have been evaluated
under section 7. Formal section 7 consultations have been conducted on the following fisheries
that NOAA Fisheries has determined are likely to adversely affect threatened and endangered sea
turtles : American lobster, Atlantic bluefish, Atlantic herring, Atlantic mackerel/squid/Atlantic
butterfish, Atlantic sea scallop, dolphin/wahoo, monkfish, northeast multispecies, red crab, skate,
spiny dogfish, southeastern shrimp trawl fishery, commercial directed shark, summer
flounder/scup/black sea bass fisheries, and tilefish. An Incidental Take Statement (ITS) has been
issued for the take of sea turtles in each of the fisheries. A summary of each consultation is
provided below but more detailed information can be found in the respective opinions.
The American lobster trap fishery has been identified as a source of gear causing serious injuries
and mortality of leatherback sea turtles. Consultation on the American lobster pot fishery was
reinitiated in 2002 to consider the effects of limited access for parts of the federal lobster
management area, and implementation of a conservation equivalency measure for state-permitted
New Hampshire lobster fishers who also held a federal lobster permit. This consultation
concluded, on October 31, 2002, that the proposed action was not likely to jeopardize the
continued existence of leatherbacks but was expected to result in the take of one additional
leatherback sea turtle biennially. NOAA Fisheries reinitiated consultation on the federal lobster
fishery on July 29, 2003, because of its impacts on right whale. This consultation is on-going but
is not expected to reconsider the effects of the fishery on leatherbacks.
The Atlantic Bluefish fishery may pose a risk to protected marine mammals, but is most likely to
interact with sea turtles (primarily Kemp’s ridley and loggerheads) given the time and locations
where the fishery occurs. Gillnets are the primary gear used to commercially land bluefish.
Turtles can become entangled in the buoy lines of the gillnets or in the net panels.
Section 7 consultation was completed on the Atlantic Herring FMP on September 17, 1999, and
concluded that the federal herring fishery may adversely affect loggerhead, leatherback, Kemp’s
ridley, and green sea turtles as a result of capture in gear used in the fishery. NOAA Fisheries
currently authorizes the use of trawl, purse seine, and gillnet gear in the commercial herring
fishery (64 FR 4030). There is no direct evidence of takes of ESA-listed species in the herring
fishery from the NOAA Fisheries sea sampling program. However, observer coverage of this
fishery has been minimal. Sea turtles have been captured in comparable gear used in other
fisheries that occur in the same area as the herring fishery. Because much of the herring fishery
occurs in state waters, the fishery is managed in these waters under the guidance of the Atlantic
States Marine Fisheries Commission (ASMFC). The ASMFC plan, implemented through
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regulations promulgated by member states, is expected to benefit sea turtles by reducing effort in
the herring fishery.
The Atlantic Mackerel/Squid/Atlantic Butterfish fishery is known to take sea turtles. Several
types of gillnet gear may be used in the mackerel/squid/butterfish fishery. Other gear types that
may be used in this fishery include midwater and bottom trawl gear, pelagic longline/hook-andline/handline, pot/trap, dredge, poundnet, and bandit gear. Entanglements or entrapments of sea
turtles have been recorded in one or more of these gear types.
It was previously believed that the Atlantic Sea Scallop fishery was unlikely to take sea turtles
given differences in depth and temperature preferences for sea turtles and the optimal areas
where the fishery occurs. However, after the reopening of a closed area in the mid-Atlantic, and
the accumulation of more extensive observer effort, NOAA Fisheries initiated formal section 7
consultation on the fishery. NOAA Fisheries concluded that operation of the fishery may
adversely affect loggerhead, Kemp’s ridley, green, and leatherback sea turtles as a result of
capture in scallop dredge and/or trawl gear. Consultation was reinitiated in 2003 following
receipt of additional information on the capture of sea turtles in scallop dredge gear. A new ITS
was provided for sea turtles. NOAA Fisheries anticipates additional information from the
Northeast Fisheries Science Center in 2004 may result in reinitiation of consultation.
The FMP for the Dolphin/Wahoo fishery was approved in December 2003. NOAA Fisheries
conducted a formal section 7 consultation to consider the effects of implementation of the FMP
on sea turtles. The biological opinion concluded that loggerhead, leatherback, hawksbill, green,
and Kemp's ridley sea turtles may be adversely affected by operation of the fishery. However,
the proposed action was not expected to jeopardize the continued existence of any of these
species. An ITS has been provided.
The federal Monkfish fishery occurs in all waters under federal jurisdiction from Maine to the
North Carolina/South Carolina border. The current commercial fishery operates primarily in the
deeper waters of the Gulf of Maine, Georges Bank, and southern New England, and in the MidAtlantic. The monkfish fishery uses several gear types that may entangle sea turtles, including
gillnet and trawl gear. NOAA Fisheries reinitiated consultation on the Monkfish FMP on May 4,
2000, in part, to reevaluate the effects of the monkfish gillnet fishery on sea turtles. A new ITS
was provided for the take of sea turtles in the fishery as a result of capture in monkfish gillnet
and trawl gear. Consultation was subsequently reinitiated in 2002 and 2003 to consider, first, the
one year delay in reducing Days-at-Sea (DAS) to zero (which would have effectively eliminated
directed monkfish fishing effort) and then elimination of the DAS reduction altogether. A new
ITS was provided for sea turtles in each case. Reducing DAS to zero would have likely been of
benefit to sea turtles by eliminating directed gillnet and trawl effort in the fishery. In March
2002, NOAA Fisheries published new restrictions for the use of gillnets with larger than 8 inch
(20.3 cm) stretched mesh, in federal waters (3-200 nautical miles) off of North Carolina and
Virginia. These restrictions were published in an Interim Final Rule under the authority of the
Endangered Species Act (67 FR 13098) and were implemented to reduce the impact of the
3-29

monkfish and other large-mesh gillnet fisheries on endangered and threatened species of sea
turtles in areas where they are known to concentrate. Following review of public comments
submitted on the Interim Final Rule, NOAA Fisheries published a Final Rule on December 3,
2002, that establishes the restrictions on an annual basis. These measures are in addition to
Harbor Porpoise Take Reduction Plan measures in place that prohibit the use of large-mesh
gillnets in southern Mid-Atlantic waters (territorial and federal waters from Delaware through
North Carolina out to 72° 30'W longitude) from February 15-March 15, annually. Operation of
the gillnet sector of the monkfish fishery is further modified by management measures
implemented under the Atlantic Large Whale Take Reduction Plan (ALWTRP).
Multiple gear types are used in the Northeast Multispecies fishery. However, the gear type of
greatest concern is sink gillnet gear that can entangle sea turtles (i.e., in buoy lines and/or net
panels). The northeast multispecies sink gillnet fishery has historically occurred from the
periphery of the Gulf of Maine to Rhode Island in water as deep as 60 fathoms. In recent years,
more of the effort in the fishery has occurred in offshore waters and into the Mid-Atlantic.
Participation in this fishery has declined because extensive groundfish conservation measures
have been implemented; the latest of these occurring under Amendment 13 to the Multispecies
FMP. Effort in the fishery is expected to be significantly reduced as a result of the Amendment
13 measures.
The Red crab fishery is a pot/trap fishery that occurs in deep waters along the continental slope.
There have been no recorded takes of ESA-listed species in the red crab fishery. However, given
the type of gear used in the fishery, takes of loggerhead and leatherback sea turtles may be
possible where gear overlaps with the distribution of ESA-listed species. An ITS has been
provided.
Traditionally, the main gear types used in the Skate fishery include mobile otter trawls, gillnet
gear, hook and line, and scallop dredges, although bottom trawling is by far the most common
gear type, accounting for 94.5% of skate landings. Gillnet gear is the next most common gear
type, accounting for 3.5% of skate landings. The Northeast skate complex is comprised of seven
different skate species. The seven species of skate are distributed along the coast of the northeast
U.S. from the tide line to depths exceeding 700m (383 fathoms). There have been no recorded
takes of ESA-listed species in the skate fishery. However, given that sea turtles interactions with
trawl and gillnet gear have been observed in other fisheries, sea turtle takes in gear used in the
skate fishery may be possible where the gear and sea turtle distribution overlap. Section 7
consultation on the new Skate FMP was completed July 24, 2003, and concluded that
implementation of the Skate FMP may adversely affect ESA-listed sea turtles as a result of
interactions with (capture in) gillnet and trawl gear. An ITS was provided.
The primary gear types for the Spiny dogfish fishery are sink gillnets, otter trawls, bottom
longline, and driftnet gear. Spiny dogfish are landed in every state from Maine to North
Carolina, throughout a broad area with the distribution of landings varying by area and season.
During the fall and winter months, spiny dogfish are captured principally in Mid-Atlantic waters
3-30

from New Jersey to North Carolina. During the spring and summer months, spiny dogfish are
landed mainly in northern waters from NY to ME. Sea turtles can be incidentally captured in all
gear sectors of this fishery. NOAA Fisheries reinitiated consultation on the Spiny Dogfish FMP
on May 4, 2000, to reevaluate, in part, the effects of the spiny dogfish gillnet fishery on sea
turtles. A new ITS has been provided for the take of sea turtles in the fishery.
The FMP for spiny dogfish called for a 30% reduction in quota allocation levels for 2000 and a
90% reduction in 2001. Although there have been delays in implementing the plan, quota
allocations are expected to be substantially reduced over the 4½ year rebuilding schedule which
should result in a substantial decrease in effort directed at spiny dogfish. The reduction in effort
should be of benefit to protected species by reducing the number of gear interactions that occur.
The Southeast shrimp trawl fishery affects more sea turtles than all other activities combined
(NRC 1990). On December 2, 2002, NOAA Fisheries completed the opinion for shrimp trawling
in the southeastern United States under proposed revisions to the TED regulations (68 FR 8456,
February 21, 2003). This opinion determined that the shrimp trawl fishery under the revised
TED regulations would not jeopardize the continued existence of any sea turtle species. This
determination was based, in part, on the opinion’s analysis that shows the revised TED
regulations are expected to reduce shrimp trawl related mortality by 94 percent for loggerheads
and 97 percent for leatherbacks.
The Summer Flounder, Scup and Black Sea Bass fisheries are known to interact with sea turtles.
Summer flounder, scup and black sea bass are managed under one FMP since these species
occupy similar habitat and are often caught at the same time. They are present in offshore waters
throughout the winter and migrate and occupy inshore waters throughout the summer. The
primary gear types used in the summer flounder, scup and black sea bass fisheries are mobile
trawl gear, pots and traps, gillnets, pound nets, and handlines. Significant measures have been
developed to reduce the take of sea turtles in summer flounder trawls and trawls that meet the
definition of a summer flounder trawl (which would include fisheries for other species like scup
and black sea bass) by requiring the use TEDs throughout the year for trawl nets fished from the
North Carolina/South Carolina border to Oregon Inlet, North Carolina and seasonally (March
16-January 14) for trawl vessels fishing between Oregon Inlet, North Carolina and Cape Charles,
Virginia. Developmental work is also ongoing for a TED that will work in the flynets used in the
summer flounder fisheries. The gillnet, pot gear and staked trap sectors could also entangle
whales and sea turtles. As a result of new information not considered in previous consultations,
NOAA Fisheries has reinitiated section 7 consultation on this FMP to consider the effects of the
fisheries on sea turtles.
The North Carolina inshore fall southern flounder gillnet fishery was identified as a source of
large numbers of sea turtle mortalities in 1999 and 2000, especially loggerhead sea turtles. In
2001, NOAA Fisheries issued an ESA section 10 permit to North Carolina with mitigative
measures for the southern flounder fishery. Subsequently, the sea turtle mortalities in these

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fisheries were drastically reduced. The reduction of sea turtle mortalities in these fisheries
reduces the negative effects these fisheries have on the environmental baseline.
The management unit for the Tilefish FMP is all golden tilefish under U.S. jurisdiction in the
Atlantic Ocean north of the Virginia/North Carolina border. Tilefish have some unique habitat
characteristics, and are found in a warm water band (8-18º C) approximately 250 to 1200 feet
deep on the outer continental shelf and upper slope of the U.S. Atlantic coast. Because of their
restricted habitat and low biomass, the tilefish fishery in recent years has occurred in a relatively
small area in the Mid-Atlantic Bight, south of New England and west of New Jersey. Section 7
consultation was completed on this newly regulated fishery in March 2001. An ITS is provided
for loggerhead and leatherback sea turtles.
Formal Section 7 consultation has also been conducted for the issuance of an Exempted Fisheries
Permit (EFP) for the collection of horseshoe crabs from the Carl N. Shuster, Jr. Federal
Horseshoe Crab Reserve (in federal waters off of the mouth of Delaware Bay), and for an EFP
for Jonah crab. The EFP for the collection of horseshoe crabs was first issued in October 2001
and includes an ITS for loggerhead sea turtles (NOAA Fisheries 2001b). Horseshoe crabs
collected under this permit are used for data collection on the species and to obtain blood for
biomedical purposes. The EFP for Jonah crab was issued to the Maine Department of Marine
Fisheries to allow lobster trap fishers to fish additional (modified) lobster traps in federal waters
off of Maine in order to determine the traps efficiency at catching Jonah crabs while excluding
lobster. The biological opinion concluded, in part, that the proposed activities may adversely
affect but were not likely to jeopardize the continued existence of leatherback sea turtles. An ITS
as well as non-discretionary RPMs and discretionary Conservation Recommendations were
provided to address the anticipated take of leatherback sea turtles.
Vessel Operations
Potential sources of adverse effects from federal vessel operations in the action area and
throughout the range of sea turtles include operations of the U.S. Navy (USN) and Coast Guard
(USCG), the Environmental Protection Agency, the National Oceanic and Atmospheric
Administration (NOAA), and the COE. NOAA Fisheries has conducted formal consultations
with the USCG, the USN, and NOAA on their vessel operations. Through the section 7 process,
where applicable, NOAA Fisheries has and will continue to establish conservation measures for
all these agency vessel operations to avoid or minimize adverse effects to listed species. At the
present time, however, they present the potential for some level of interaction.
In addition to vessel operations, other military activities including training exercises and
ordnance detonation also affect sea turtles and cetaceans. Consultations on individual activities
have been completed, but no formal consultation on overall USCG or USN activities in any
region has been completed at this time.

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Dredging
The construction and maintenance of federal navigation channels has also been identified as a
source of sea turtle mortality. Hopper dredges move relatively rapidly (compared to sea turtle
swimming speeds) and can entrain and kill sea turtles, presumably as the drag arm of the moving
dredge overtakes the slower moving sea turtle. A regional opinion with the COE’s South
Atlantic Division has been completed for the southeastern Atlantic waters. Consultation on a
new regional opinion for the COE’s Gulf of Mexico hopper dredging operations was completed
in November, 2003.
Oil and Gas Exploration
The COE and the Minerals Management Service (MMS) authorize oil and gas exploration, well
development, production, and abandonment/rig removal activities that also may adversely affect
sea turtles. Both of these agencies have consulted with NOAA Fisheries on these types of
activities. These activities include the use of seismic arrays for oil and gas exploration in the
Gulf of Mexico, the impacts of which have been addressed in opinions for individual and multilease sales. These impacts are expected to result from vessel strikes, noise, marine debris, and
the use of explosives to remove oil and gas structures.
Electrical Generating Plants
Another action with federal oversight (the Federal Energy Regulatory Commission and the
Nuclear Regulatory Agency) which has impacts on sea turtles is the operation of electrical
generating plants. Sea turtles entering coastal or inshore areas have been affected by entrainment
in the cooling-water systems of electrical generating plants, though it is important to note that
almost all of the turtles are caught and released alive; NOAA Fisheries estimates the survival rate
at 98.5% or greater (NMFS 1997). Biological opinions have already been written for a number
of electrical generating plants, and others are currently undergoing section 7 consultation.
3.5.1.2 State or Private Actions
Vessel Traffic
Commercial traffic and recreational pursuits can adversely effect sea turtles through propeller
and boat strikes. Private vessels participate in high speed marine events concentrated in the
southeastern United States and are a particular threat to sea turtles. The magnitude of these
marine events is not currently known. NOAA Fisheries and the USCG are in early consultation
on these events, but a thorough analysis has not been completed. The Sea Turtle Stranding and
Salvage Network (STSSN) also reports many records of vessel interaction (propeller injury) with
sea turtles off coastal states such as New Jersey and Florida, where there are high levels of vessel
traffic.
State Fisheries
Various fishing methods used in state fisheries, including trawling, pot fisheries, fly nets, and
gillnets are known to incidentally take listed species, but information on these fisheries is sparse
(NMFS SEFSC 2001). Although few of these state regulated fisheries are currently authorized to
3-33

incidentally take listed species, several state agencies have approached NOAA Fisheries to
discuss applications for a section 10(a)(1)(B) incidental take permit. Since NOAA Fisheries’
issuance of a section 10(a)(1)(B) permit requires formal consultation under section 7 of the ESA,
the effects of these activities are considered in section 7 consultation. Any fisheries that come
under a section 10(a)(1)(B) permit in the future will likewise be subject to section 7 consultation.
Although the past and current effects of these fisheries on listed species is currently not
determinable, NOAA Fisheries believes that ongoing state fishing activities may be responsible
for seasonally high levels of observed strandings of sea turtles on both the Atlantic and Gulf of
Mexico coasts. Most of the state data are based on extremely low observer coverage or sea
turtles were not part of data collection; thus, these data provide insight into gear interactions that
could occur but are not indicative of the magnitude of the overall problem. In addition to the
lack of interaction data, there is another issue that complicates the analysis of impacts to sea
turtles from these fisheries. Certain gear types may have high levels of sea turtle takes, but very
low rates of serious injury or mortality. For example, the hook and line takes rarely result in
death, but trawls and gillnets frequently do. Leatherbacks seem to be susceptible to a more
restricted list of fisheries, while the hard shelled turtles, particularly loggerheads, seem to appear
in data on almost all of the state fisheries.
The North Carolina Observer program documented 33 flynet trips from November through April
of 1991-1994 and recorded no turtles caught in 218 hours of trawl effort. However, a NOAA
Fisheries- observed vessel fished for summer flounder for 27 tows with an otter trawl equipped
with a TED and then fished for weakfish and Atlantic croaker with a flynet that was not equipped
with a TED. They caught 1 loggerhead in 27 TED-equipped tows and 7 loggerheads in 9 flynet
tows without TEDs. In addition, the same vessel using the flynet on a previous trip took 12
loggerheads in 11 out of 13 observed tows targeting Atlantic croaker. NOAA Fisheries is testing
designs for TEDs that may be required in the flynet fishery in the future.
Other state bottom trawl fisheries that are suspected of incidentally capturing sea turtles are the
horseshoe crab fishery in Delaware (Spotila et al. 1998) and the whelk trawl fishery in South
Carolina (S. Murphy, pers. comm. to J. Braun-Mcneill, November 27, 2000) and Georgia (M.
Dodd, pers. comm. to J. Braun-McNeill, December 21, 2000). In South Carolina, the whelk
trawling season opens in late winter and early spring when offshore bottom waters are > 55ºF.
One criterion for closure of this fishery is water temperature: whelk trawling closes for the
season and does not reopen throughout the state until six days after water temperatures first reach
64ºF in the Fort Johnson boat slip. Based on the South Carolina Department of Natural
Resources Office of Fisheries Management data, approximately six days will usually lapse before
water temperatures reach 68ºF, the temperature at which sea turtles move into state waters (D.
Cupka, pers. comm.). From 1996-1997, observers onboard whelk trawlers in Georgia reported a
total of three Kemp's ridley, two green, and two loggerhead sea turtles captured in 28 tows for a
CPUE of 0.3097 turtles/100 ft net hour. As of December 2000, TEDS are required in Georgia
state waters when trawling for whelk. There has also been one report of a loggerhead captured in
a Florida try net (W. Teas, pers. comm.). Trawls for cannonball jellyfish may also be a source of
interactions.
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A detailed summary of the gillnet fisheries currently operating along the mid- and southeast U.S.
Atlantic coastline, which are known to incidentally capture loggerheads, can be found in the
TEWG reports (1998, 2000). Although all or most nearshore gillnetting is prohibited by state
regulations in state waters of South Carolina, Georgia, Florida, Louisiana, and Texas, gillnetting
in other states’ waters and in federal waters does occur. Of particular concern are the nearshore
and inshore gillnet fisheries of the mid-Atlantic operating in Rhode Island, Connecticut, New
York, New Jersey, Delaware, Maryland, Virginia, and North Carolina state waters and/or federal
waters. Incidental captures in these gillnet fisheries (both lethal and non-lethal) of loggerhead,
leatherback, green and Kemp's ridley sea turtles have been reported (W. Teas, pers. comm., J.
Braun-McNeill pers. comm.). In addition, illegal gillnet incidental captures have been reported
in South Carolina, Florida, Louisiana and Texas (NMFS SEFSC 2001).
Georgia and South Carolina prohibit gillnets for all but the shad fishery. This fishery was
observed in South Carolina for one season by the NOAA Fisheries SEFSC (McFee et al. 1996).
No takes of protected species were observed. Florida banned all but very small nets in state
waters, as has the state of Texas. Louisiana, Mississippi and Alabama have also placed
restrictions on gillnet fisheries within state waters such that very little commercial gillnetting
takes place in southeast waters, with the exception of North Carolina. Gillnetting activities in
North Carolina associated with the southern flounder fishery had been implicated in large
numbers of sea turtle mortalities. The Pamlico Sound portion of that fishery was closed and has
subsequently been reopened under a section 10(a)(1)(B) permit.
Pound nets are a passive, stationary gear that are known to incidentally capture loggerhead sea
turtles in Massachusetts (R. Prescott pers. comm.), Rhode Island, New Jersey, Maryland (W.
Teas pers. comm.), New York (Morreale and Standora 1998), Virginia (Bellmund et al. 1987)
and North Carolina (Epperly et al. 2000). Although pound nets are not a significant source of
mortality for loggerheads in New York (Morreale and Standora 1998) and North Carolina
(Epperly et al. 2000), they have been implicated in the stranding deaths of loggerheads in the
Chesapeake Bay from mid-May through early June (Bellmund et al. 1987). The turtles were
reported entangled in the large mesh (>8 inches) pound net leads (NMFS SEFSC 2001).
Incidental captures of loggerheads in fish traps set in Massachusetts, Rhode Island, New
York, and Florida have been reported (W. Teas, pers. comm.). Although no
incidental captures have been documented from fish traps set in North Carolina and Delaware
(Anon 1995), they are another potential anthropogenic impact to loggerheads and other
sea turtles. Lobster pot fisheries are prosecuted in Massachusetts (Prescott 1988), Rhode Island
(Anon 1995), Connecticut (Anon 1995) and New York (S. Sadove, pers. comm.). Although they
are more likely to entangle leatherback sea turtles, lobster pots set in New York are also known
to entangle loggerhead sea turtles. No incidental capture data exist for the other states. Long
haul seines and channel nets in North Carolina are known to incidentally capture loggerhead and
other sea turtles in the sounds and other inshore waters (J. Braun-McNeill, pers. comm.). No
lethal takes have been reported (NMFS SEFSC 2001).

3-35

Observations of state recreational fisheries have shown that loggerhead, leatherback, Kemp’s
ridley, and green sea turtles are known to bite baited hooks, and loggerheads and Kemp’s ridleys
frequently ingest the hooks. Recreational fishermen have reported hooking turtles when fishing
from boats, piers, and beach, banks, and jetties. Commercial fishermen fishing for reef fish and
for sharks with both single rigs and bottom longlines have also reported hooked turtles (NMFS
2001). A detailed summary of the known impacts of hook and line incidental captures to
loggerhead sea turtles can be found in the TEWG reports (1998, 2000).
Coastal Development
Beachfront development, lighting and beach erosion control all are ongoing activities along the
Gulf of Mexico and Atlantic coasts. These activities potentially reduce or degrade sea turtle
nesting habitats or interfere with hatchling movement to sea. Nocturnal human activities along
nesting beaches may also discourage sea turtles from nesting sites. The extent to which these
activities reduce sea turtle nesting and hatchling production is unknown. However, more and
more coastal counties are adopting stringent protective measures to protect hatchling sea turtles
from the disorienting effects of beach lighting.

3.5.1.3 Other Sources of Impacts
International
For sea turtle species in the Atlantic, international activities, particularly fisheries, are significant
factors impacting populations. The U.S. and 26 other nations participate in longline fishing
throughout the western North Atlantic Ocean and the relative proportion of total hooks fished by
the U.S. fleet is small compared to the cumulative total hooks fished by foreign fleets. As with
U.S. fleets, sea turtles are incidentally captured in foreign fleets (NMFS SEFSC 2001). Takes of
pelagic juvenile loggerheads in U.S. and international longline fisheries as a whole are large and
NMFS SEFSC (2001) concludes that it could alter population trends. Takes in international
gillnet fisheries are also known to be prevalent. Additional information on the impacts of
international fisheries is found in NMFS SEFSC (2001) and Lewison et al. (2004). NOAA
Fisheries estimates that, each year, thousands of sea turtles of all species are incidentally caught
and a proportion of them killed incidentally or intentionally by international activities. The
impact of international fisheries is a significant factor in the baseline inhibiting sea turtle
recovery.
Significant anthropogenic impacts threaten nesting populations of all species in areas outside of
the U.S. These impacts include poaching of eggs, immatures and adults as well as beach
development problems. There are other more indirect factors; for a complete list refer to NOAA
Fisheries SEFSC (2001).

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Marine Pollution
A number of activities that may indirectly affect listed species in the action area of this
consultation include discharges from wastewater systems, dredging, ocean dumping and disposal,
aquaculture, recreational fishing, and anthropogenic marine debris. The impacts from these
activities are difficult to measure. Where possible, conservation actions are being implemented
to monitor or study impacts from these sources. Close coordination is occurring through the
section 7 process on both dredging and disposal sites to develop monitoring programs and ensure
that vessel operators do not contribute to vessel-related impacts.
Sources of pollutants in Atlantic and Gulf of Mexico coastal regions include atmospheric loading
of pollutants such as PCBs, storm water runoff from coastal towns, cities and villages, runoff into
rivers emptying into the bays, groundwater and other discharges, and river input and runoff.
Nutrient loading from land-based sources such as coastal community discharges is known to
stimulate plankton blooms in closed or semi-closed estuarine systems. The effects on larger
embayments is unknown. Although pathological effects of oil spills have been documented in
laboratory studies of marine mammals and sea turtles (Vargo et al. 1986), the impacts of many
other anthropogenic toxins have not been investigated.
Disease
A little understood disease is posing a new threat to loggerhead sea turtles. Between the period
of September 2000 to January 2001, 45 debilitated and 95 dead loggerhead turtles have been
found in south Florida between Indian River and Charlotte Counties, elevating stranding data for
this period to more than 3 times the previous 10-year average (Foley, pers. comm., 2000). These
numbers may represent only 10 to 20% of the turtles that have been affected by this disease
because many dead or dying turtles likely never wash ashore. If the agent responsible for
debilitating these turtles re-emerges in Florida, the scope of this die-off may increase
substantially. In addition, if the agent is infectious, nesting females could spread the disease
throughout the range of the adult loggerhead population. Symptoms of the unknown disease
include extreme lethargy and pneumonia. Of the diseased turtles found alive, even with
extensive care, many have died and none have fully recovered. The cause of the disease has yet
to be determined but potential causes include bacteria, virus, or exposure to some toxin.
Acoustic impacts
NOAA Fisheries and the USN have been working cooperatively to establish a policy for
monitoring and managing acoustic impacts from anthropogenic sound sources in the marine
environment. Acoustic impacts to sea turtles can include temporary or permanent injury, habitat
exclusion, habituation, and disruption of other normal behavior patterns.
3.5.1.4 Conservation and Recovery Actions Benefitting Sea Turtles
NOAA Fisheries has implemented a series of regulations aimed at reducing potential for
incidental mortality of sea turtles in commercial fisheries. In particular, NOAA Fisheries has
required the use of TEDs in southeast U.S. shrimp trawls since 1989 and in summer flounder
3-37

trawls in the mid-Atlantic area (south of Cape Charles, Virginia) since 1992. It has been
estimated that TEDs exclude 97 percent of the sea turtles caught in such trawls. These
regulations have been refined over the years to ensure that TED effectiveness is maximized
through proper placement and installation, configuration (e.g., width of bar spacing), floatation,
and more widespread use. Analyses by Epperly and Teas (2002) indicated that the minimum
requirements for the escape opening dimensions in TEDs in use at that time were too small, and
that as many as 47 percent of the loggerheads stranding annually along the Atlantic Seaboard and
Gulf of Mexico were too large to fit through existing openings. On February 21, 2003, NOAA
Fisheries published a final rule to require larger escape openings in TEDs used in the southeast
shrimp trawl fishery (68 FR 8456, February 21, 2003). Based upon the analyses in Epperly et al.
(2002), leatherback and loggerhead sea turtles will greatly benefit from the new regulations, with
expected reductions of 97 percent and 94 percent, respectively, in mortality from shrimp
trawling. Several states have regulations requiring the use of TEDs in state-regulated trawl
fisheries, and the federal regulations also apply in state waters.
In 1993 (with a final rule implemented in 1995), NOAA Fisheries established a Leatherback
Conservation Zone to restrict shrimp trawl activities from the coast of Cape Canaveral, Florida,
to the North Carolina/Virginia border. This provided for short-term closures when high
concentrations of normally pelagically-distributed leatherbacks are recorded in near coastal
waters where the shrimp fleet operates. This measure was necessary because, due to their size,
adult leatherbacks were larger than the escape openings of most NOAA Fisheries-approved
TEDs. With the implementation of the new TED rule requiring larger opening sizes on all TEDs,
the reactive emergency closures within the Leatherback Conservation Zone became unnecessary,
and the Leatherback Conservation Zone was removed from the regulations.
NOAA Fisheries is also working to develop a TED which can be effectively used in a type of
trawl known as a flynet, which is sometimes used in the mid-Atlantic and Northeast fisheries to
target sciaenids and bluefish. Limited observer data indicate that takes can be quite high in this
fishery. Prototype designs have been tested since December 2002, but an effective TED for this
fishery has not yet been developed. Development of a larger TED for the winter trawl fishery is
also underway.
NOAA Fisheries closed part of Pamlico Sound to the setting of gillnets targeting southern
flounder in fall 1999 after the strandings of relatively large numbers of loggerhead and Kemp’s
ridley sea turtles on inshore beaches. This is a state-regulated fishery. NOAA Fisheries also
closed the waters north of Cape Hatteras to 38° N latitude, including the mouth of the
Chesapeake Bay, to large (> 6 inch stretched) mesh gillnets for 30 days in mid-May 2000 due to
the large numbers of loggerhead strandings in North Carolina, and will continue to implement
such proactive measures as necessary. A large proportion of these stranded loggerheads was
assumed to be from the northern subpopulation. This assumption is partly supported by analyses
conducted by Bass et al. (1999) on genetic samples collected from sea turtles stranding on U.S.
Atlantic and Gulf of Mexico shores. The northern subpopulation accounted for 25-28 percent of
the animals that stranded off the Carolinas, and 46 percent of the animals sampled that stranded
3-38

in the northernmost area sampled, Virginia (TEWG 2000). Most recently, on October 27, 2000,
the North Carolina Division of Marine Fisheries (NCDMF) closed waters in the southeastern
portion of the Pamlico Sound as a result of elevated takes by the commercial large-mesh flounder
gillnet fishery. The fishery was closed when anticipated incidental take levels were met for green
turtles. The NCDMF estimated that there were 50 loggerheads captured at the time of closure
and that 44 of those had been drowned (NMFS SEFSC 2001, Part 1). The fishery has
subsequently been reopened under a section 10(a)(1)(B) permit.
In March 2002, NOAA Fisheries published new restrictions for the use of gillnets with larger
than 8 inch (20.3 cm) stretched mesh, in federal waters (3-200 nautical miles) off of North
Carolina and Virginia. These restrictions were published in an Interim Final Rule under the
authority of the Endangered Species Act (67 FR 13098) and were implemented to reduce the
impact of the monkfish and other large-mesh gillnet fisheries on endangered and threatened
species of sea turtles in areas where sea turtles are known to concentrate. Following review of
public comments submitted on the Interim Final Rule, NOAA Fisheries published a Final Rule
on December 3, 2002, that establishes the restrictions on an annual basis. As a result, gillnets
with larger than 8 inch stretched mesh are not allowed in federal waters (3-200 nautical miles)
north of the North Carolina/South Carolina border at the coast to Oregon Inlet at all times; north
of Oregon Inlet to Currituck Beach Light, North Carolina from March 16 through January 14;
north of Currituck Beach Light, North Carolina to Wachapreague Inlet, Virginia from April 1
through January 14; and, north of Wachapreague Inlet, Virginia to Chincoteague, Virginia from
April 16 through January 14. Federal waters north of Chincoteague, Virginia are not affected by
these new restrictions although NOAA Fisheries is looking at additional information to
determine whether expansion of the restrictions are necessary to protect sea turtles as they move
into northern Mid-Atlantic and New England waters. These measures are in addition to Harbor
Porpoise Take Reduction Plan measures that prohibit the use of large-mesh gillnets in southern
Mid-Atlantic waters (territorial and federal waters from Delaware through North Carolina out to
72° 30'W longitude) from February 15-March 15, annually.
Existing information indicates that pound nets with large mesh and stringer leaders as used in the
Chesapeake Bay incidentally take sea turtles. To address the high and increasing level of sea
turtle strandings, NOAA Fisheries published a temporary rule in June 2001 (66 FR 33489) that
prohibited fishing with pound net leaders with a mesh size measuring 8 inches or greater (20.3
cm) and pound net leaders with stringers in mainstream waters of the Chesapeake Bay and its
tributaries for a 30-day period beginning June 19, 2001. NOAA Fisheries subsequently
published an Interim Final Rule in 2002 (67 FR 41196, June 17, 2002) that further addressed the
take of sea turtles in large-mesh pound net leaders and stringer leaders used in the Chesapeake
Bay and its tributaries. Following new observations of sea turtle entanglements in pound net
leaders in the spring of 2003, NOAA Fisheries issued a temporary final rule (68 FR 41942, July
16, 2003) that restricted all pound net leaders throughout Virginia’s waters of the Chesapeake
Bay and a portion of its tributaries from July 16-July 30, 2003. As a follow-up to this action,
NOAA Fisheries recently published a final rule (69 FR 24997, May 5, 2004) that prohibits the
use of all pound net leaders, set with the inland end of the leader greater than 10 horizontal feet
3-39

(3m) from the, mean low water line, from May 6 to July 15 each year in the mainstream waters of
the Chesapeake Bay, south of 37° 19.0' N. latitude and west of 76° 13.0' W. longitude, and all
waters south of 37° 13.0' N. latitude to the Chesapeake Bay Bridge Tunnel at the mouth of the
Chesapeake Bay, and the James and York Rivers downstream of the first bridge in each tributary.
Outside this area, the prohibition of leaders with greater than or equal to 12 inches (30.5 cm)
stretched mesh and leaders with stringers, as established by the June 17, 2002, interim final rule,
will apply from May 6 to July 15 each year. The final rule also includes a framework mechanism
by which NMFS may take additional action as necessary.
As described above for the Atlantic sea scallop fishery, NOAA Fisheries received new
information in 2001 which demonstrated that scallop dredge gear posed a risk of injury and
mortality for hard-shelled sea turtles as a result of being captured in the dredge. Subsequently,
industry representatives and interested parties began working in conjunction with NOAA
Fisheries, Northeast Fisheries Science Center to test a modified dredge that is intended to reduce
the risk of sea turtle captures in the gear. The first year of the study produced promising results.
Further testing is planned for 2004.
NOAA Fisheries has also been active in public outreach efforts to educate fishermen regarding
sea turtle handling and resuscitation techniques. As well as making this information widely
available to all fishermen, NOAA Fisheries recently conducted a number of workshops with
HMS pelagic longline fishermen to discuss bycatch issues including protected species, and to
educate them regarding handling and release guidelines. NOAA Fisheries intends to continue
these outreach efforts and hopes to reach all fishermen participating in the HMS pelagic longline
fishery over the next one to two years. There is also an extensive network of Sea Turtle
Stranding and Salvage Network participants along the Atlantic and Gulf of Mexico coasts who
not only collect data on dead sea turtles, but also rescue and rehabilitate any live stranded sea
turtles.
Loggerheads, leatherbacks, greens, and Kemp’s ridleys are known to bite a baited hook,
frequently ingesting the hook. Hooked turtles have been reported by the public fishing from
boats, piers, beaches, banks, and jetties. Necropsies have revealed hooks internally, which often
were the cause of death. NOAA Fisheries currently is exploring adding questions about
encounters with sea turtles to intercept interviews of recreational fishermen conducted by the
Texas Parks and Wildlife Department under the auspices of the Marine Recreational Fishery
Statistics Surveys conducted throughout the Gulf of Mexico and along the Atlantic Coast as well
as adding such information to the MRFSS database. NOAA Fisheries is also considering
questioning recreational fishermen aboard headboats throughout the southeast U.S. Atlantic and
the Gulf of Mexico to quantify their encounters with sea turtles (TEWG 2000). A detailed
summary of the impact of hook and line incidental captures on loggerhead sea turtles can be
found in the TEWG reports (1998, 2000).

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The Recovery Plans for loggerhead and Kemp’s ridley sea turtles are in the process of being
updated. Recovery teams comprised of sea turtle experts have been convened and are currently
working towards revising these plans based upon the latest and best available information.

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4.0

EFFECTS OF THE PROPOSED ACTION

In this section of the opinion, we assess whether it is reasonable to expect the HMS pelagic
longline fishery, as conducted under the proposed regulations, to appreciably reduce the
likelihood of survival and recovery of threatened and endangered species in the wild. This
section begins with a discussion of the factors to be considered in that assessment. Specifically,
we will assess the types of effects expected from the proposed action and discuss some of the
available data and assumptions used in making our overall assessment. Then, we will look at the
extent of those effects.
4.1 Approach to the Effects Analysis
4.1.1

Scope of the Analysis

Although all six species of sea turtles are potentially impacted by the Atlantic pelagic longline
fishery, leatherback and loggerhead turtles are by far the dominant species caught. Interactions
with green, Kemp’s ridley, hawksbill, and olive ridley turtles occur only on rare occasions.
Moreover, the 2001 opinion on HMS fisheries concluded that the fisheries, as prosecuted without
the proposed regulations, would not jeopardize the continued existence of any of these less
frequently caught species. There is no new information to alter that conclusion; therefore, the
effects analysis focuses on loggerhead and leatherback sea turtles.
The analysis in this section forms the foundation for our jeopardy determination. A jeopardy
determination is reached if we would reasonably expect a proposed action to cause reductions in
numbers, reproduction, or distribution that would appreciably reduce a listed species’ likelihood
of surviving and recovering in the wild. The ESA defines an endangered species as “...in danger
of extinction throughout all or a significant portion of its range...” and a threatened species as
“...likely to become an endangered species within the foreseeable future...” Sea turtles are listed
because of their global status; on a worldwide basis, the loggerhead turtle is listed as threatened,
and the leatherback turtle is listed as endangered. A jeopardy determination must find that the
proposed action will appreciably reduce the likelihood of survival and recovery of the global
species.
The Atlantic and Pacific Ocean populations of both loggerhead and leatherback sea turtles
contribute substantially to the total reproduction, numbers, and distribution of their respective
species (see Status of the Species for population estimates). For example, the Pacific leatherback
sea turtle is at high risk of extinction (Spotila et al. 1996, Spotila et al. 2000); therefore, the
global survival of the leatherback turtle is dependent on the survival of Atlantic populations. The
loss of either population from a catastrophic event would severely impact the stability and longterm prospects of the global species. Similarly, the Pacific populations of loggerhead turtles are
small relative to the Atlantic populations, and in decline. Significant nesting of loggerhead
turtles occurred in the Indian Ocean, with the largest nesting assemblage in Oman (Ross and
Barwani 1982). However, little new information is available regarding the status of the stock in
4-1

this region. In addition, the recovery of loggerhead and leatherback sea turtles require meeting
the goals of both the Atlantic and the Pacific recovery plans. Thus, reductions in numbers,
reproduction, or distribution of either basin’s populations could potentially lead to an appreciable
reduction in a global species’ likelihood of both survival and recovery. The analysis performed
in this section will therefore focus on expected impacts to the Atlantic populations as a result of
the proposed action occurring in the Atlantic.
4.1.2

Conservative Decisions

The quantitative and qualitative analyses in this section are based upon the best available
commercial and scientific data on sea turtle biology and the effects of the proposed action.
Frequently, the best available information may include a range of values for a particular aspect
under consideration, or different analytical approaches may be applied to the same data sets. In
those cases, in keeping with the direction from the U.S. Congress to resolve uncertainty by
providing the “benefit of the doubt” to threatened and endangered species [House of
Representatives Conference Report No. 697, 96th Congress, Second Session, 12 (1979)], we will
generally select the value yielding the most conservative outcome for sea turtles (i.e., would lead
to conclusions of higher, rather than lower, risk to endangered or threatened species).
4.1.2

Consideration of Indirect Effects

When analyzing the effects of any action, it is important that the indirect effects as well as the
direct effects be considered. Indirect effects include aspects such as habitat degradation,
reduction of prey/foraging base, etc. In the case of the proposed action analyzed in this opinion,
there are no expected indirect effects to sea turtles. The operation of the longline fishery (i.e.,
vessel operations, longline gear deployment and retrieval) is not expected to impact any habitat
features of significance to sea turtles in the pelagic environment. Sea turtles do not forage on the
longline fishery’s target or bycatch species, so prey competition is not a factor. Therefore, all
analyses will be based on direct effects.
4.1.3

Consideration of Direct Effects

The gear used by the HMS pelagic longline fishery presents a significant threat to sea turtles.
Entangled or hooked turtles can drown if they cannot surface to breathe. Turtles that are released
alive may succumb to injuries sustained at the time of capture or from exacerbated trauma from
fishing hooks or lines that were ingested, entangling, or otherwise still attached when they were
released. Other turtles hooked or entangled may not die from their wounds, but may suffer
impaired swimming or foraging abilities, altered migratory behavior, and altered breeding or
reproductive patterns.
Although some studies have attempted to examine post-release mortality rates and sub-lethal
effects on sea turtles captured in longline fisheries, such long-term effects are very difficult to
monitor satisfactorily with existing technologies. Therefore, a quantitative measure of the effect
4-2

of longlining on sea turtle populations is very challenging. The following discussion summarizes
the information on how individual sea turtles are likely to respond to these interactions. The
remainder of this section focuses on quantifying direct impacts on individual animals from the
proposed action. Section 6 integrates the analysis of this section with the status of the species
and cumulative effects and uses quantitative approaches to evaluate the effects of the proposed
action on the species’ populations.
4.2 Capture on Longline Gear
4.2.1

Factors That May Attract Sea Turtles to Longline Gear

Floats
Sea turtles may be attracted to the floats used on longline gear. According to a study by Arenas
and Hall (1992), turtles show a preference for nearly submerged objects floating horizontally,
and are strongly attracted to brightly colored objects. Lab experiments have shown sea turtles
prefer bright colors (i.e., red and yellow) over dull or darker colors (i.e. black, green or blue) (e.g.
Fontaine, et al. 1985). Controlled experiments and qualitative evaluations were conducted by the
SEFSC using captive reared sea turtles to evaluate their responses to various components of
pelagic longlining gear and other stimuli. One experiment tested the attraction of sea turtles to
orange and white colored longline floats in a 80' x 35' pen enclosure. Sea turtles were introduced
into the pen with a single float treatment. Preliminary analysis of the results indicated that the
test turtles may have been more attracted to orange-colored floats than to white-colored floats (J.
Watson, SEFSC, personal communication, July 2001). Floats typically used during swordfishstyle sets are bright orange, bullet-shaped, and slightly submerged. Deep sets generally use larger
cylindrical inflatable or rigid spherical buoys and floats, and these also are typically orange in
color (L. Enriquez, NOAA Fisheries, personal communication, January 2001; e.g.
www.lindgren-pitman.com/floats.htm).
Mainline and hardware
The SEFSC also conducted evaluations at the Panama City Laboratory which involved placing
longline gear in open water pens with captive reared loggerhead turtles to investigate turtle
entanglement with various longline gear components. During these experiments, scientists
observed turtles tracking along the mainline and biting at the hardware (snaps). Turtles placed in
a pool without longline gear (i.e., control) tended to track along the outside edges of the pool.
These observations support at-sea observations by divers and remotely operated vehicles, which
indicate that turtles may be attracted to the highly visible mainline and hardware used by the
fishing industry, and that the turtles may swim along the mainline (J. Watson, SEFSC, personal
communication, August 2001).
Lightsticks
Sea turtles foraging at night may be attracted to the lightsticks, confusing them for prey or simply
investigating novel items in their environment. Lightsticks are often used by longliners targeting
swordfish in order to attract the swordfish to the bait. Whether lightsticks attract swordfish
4-3

directly or whether they attract baitfish, which in turn attract the swordfish, is not entirely clear;
however, fishermen report higher takes of swordfish when they use lightsticks. Lightsticks are
generally attached to every gangion, approximately a meter above the hook. Leatherback,
loggerhead, and olive ridley turtles are known to prey on pyrosomas, the so-called “fiery bodies”;
however, there is little information on the ingestion of lightsticks by sea turtles. In addition,
statisticians have not been able to find any correlation between sea turtle take and the proximity
of a lightstick to the hook or branchline the turtle was hooked on or entangled in. Experimental
studies have, however, indicated that juvenile sea turtles orient towards green, blue, and yellow
chemical lightsticks, and orange, green, and shaded green battery powered LEDs (Wang, et al.
2004).
Bait
Sea turtles may also be attracted to the bait used on longline gear. Four olive ridleys necropsied
after being taken dead by Hawaii-based longliners were found with bait in their stomachs (Work
2000). In addition, leatherback turtles are known to eat squid. Skillman and Balazs (1992)
speculated the lightsticks used on this gear type may have initially attracted the turtle, by
simulating natural prey. As will be discussed later, the NED experiment found significant
differences in the catch rates of loggerhead and leatherback turtle based on the bait type used. It
is not clear, however, whether it is the bait’s attractiveness, its ability to shield the hook, the
manner in which turtle feed on different baits, or a combination of behaviors, that is responsible
for the effect.
4.2.2

Entanglement

Sea turtles are particularly prone to entanglement as a result of their body configuration and
behavior. Records of stranded or entangled sea turtles reveal that fishing gear can wrap around
the neck, flipper, or body of a sea turtle and severely restrict swimming or feeding. If the sea
turtle is entangled when young, the fishing line will become tighter and more constricting as the
sea turtle grows, cutting off blood flow and causing deep gashes, some severe enough to remove
an appendage.
Pelagic longline gear is fluid and drifts according to oceanographic conditions, including wind
and waves, surface and subsurface currents, etc.; therefore, depending on both sea turtle
behavior, environmental conditions, and location of the set, turtles can become entangled in
longline gear. Sea turtles have been found entangled in gangions, mainlines and floatlines. Sea
turtles entangled in the longline fishery are most often entangled around the neck and
foreflippers, and, in the case of leatherback turtles, are often found snarled in mainlines,
floatlines, and gangions (e.g., Hoey 2000). If sea turtles become entangled in monofilament line
(mainline, gangion or float line) the gear can inflict serious wounds, including cuts, constriction,
or bleeding anywhere on a turtle’s body. In addition, entangling gear can interfere with a turtle’s
ability to swim or impair its feeding, breeding, or migration and can force the turtle to remain
submerged, causing it to drown.

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4.2.3

Hooking

In addition to being entangled in a longline, sea turtles are also injured and killed by being
hooked. Hooking can occur as a result of a variety of scenarios, some of which will depend on
foraging strategies and diving and swimming behavior of the various species of sea turtles. Sea
turtles are either hooked externally — generally in the flippers, head, shoulders, armpits, or beak
— or internally, inside the mouth or when the animal has swallowed the bait and the hook is
ingested into the gastro-intestinal tract, often a major site of hooking (E. Jacobson in Balazs et al.
1995). Whereas entanglement and foul hooking is the primary form of interaction that occurs
between leatherback turtles and the longline fishery, internal hooking is much more prevalent in
hard-shelled turtles, especially loggerheads. Internal hooking of leatherback turtles is much more
rare. As NOAA Fisheries became more aware of the differential hooking patterns for different
species of turtles and of the implications of hooking location on the severity of the injury from
longline interactions, the POP began collecting more detailed information on sea turtle hooking
location. Data on hooking location from the Atlantic longline observer program in 1999 and
2000 (in NMFS SEFSC 2001) and from the NED experiment (Watson et al. 2003) agreed
closely. For leatherback turtles, the large majority of interactions (at least 75%) are external foulhookings, usually in the front flipper, shoulder or armpit. The remainder of the interactions are
primarily entanglements without hooking; and only a few leatherbacks are hooked in the mouth.
For loggerheads, almost all interactions result from taking the bait and hook; only a very small
percentage of loggerheads are entangled or foul-hooked externally. Loggerheads caught on Jhooks most often swallow the hooks (67% of interactions in Watson et al. [2003]). The J-hook is
the standard hook style in the HMS pelagic longline fishery.
Turtles that have swallowed hooks are of the greatest concern. The esophagus is lined with
strong conical papillae directed caudally towards the stomach (White 1994). The presence of
these papillae in combination with an S-shaped bend in the esophagus make it difficult to see
hooks when looking through a turtle’s mouth, especially if the hooks have been deeply ingested.
Because of a turtle’s digestive structure, deeply-ingested hooks are also very difficult to remove
without seriously injuring the turtle. A turtle’s esophagus is attached firmly to underlying tissue;
therefore, if a turtle swallows a hook and tries to free itself or is hauled on board a vessel, the
hook can pierce the turtle’s esophagus or stomach and can pull organs from their connective
tissue. These injuries can cause the turtle to bleed internally or can result in infections, both of
which can kill the turtle.
If a hook does not lodge into, or pierce, a turtle’s digestive organs, it can pass through to the
turtle’s colon or it can pass through the turtle entirely (E. Jacobson in Balazs et al. 1995; Aguilar
et al. 1995) with little damage (Work 2000). Of 38 loggerheads deeply hooked by the Spanish
Mediterranean longline fleet and subsequently held in captivity, six loggerheads expelled hooks
after 53 to 285 days (average 118 days) (Aguilar et al. 1995). If a hook passes through a turtle’s
digestive tract without getting lodged, the hook probably has not harmed the turtle. Tissue
necrosis that may have developed around the hook may also get passed along through the turtle
as a foreign body (E. Jacobson in Balazs et al. 1995).
4-5

4.2.4

Trailing Line

Trailing line (i.e., line left on a turtle after it has been captured and released), particularly line
trailing from an ingested hook, poses a serious risk to sea turtles. Line trailing from an ingested
hook is likely to be swallowed, which may occlude the gastrointestinal tract, or it may prevent or
hamper foraging, leading to eventual death. Sea turtles that swallow monofilament still attached
to an embedded hook may suffer from the “accordion effect” described by Mediterranean sea
turtle researchers, usually fatal, whereby the intestine, perhaps by its peristaltic action in
attempting to pass the unmoving monofilament line through the alimentary canal, coils and
wraps upon itself (Pont, pers. comm. 2001). Trailing line may also become snagged on a floating
or fixed object, further entangling a turtle and potentially slicing its appendages which may affect
its ability to swim, feed, avoid predators, or reproduce. Sea turtles have been found trailing gear
that has been snagged on the bottom, or has the potential to snag, thus anchoring them in place
(Balazs 1985; Hickerson, pers. comm. 2001). Long lengths of trailing gear are likely to entangle
the turtle eventually, leading to impaired movement, constriction wounds, and potentially death.
4.2.5

Forcible Submergence

Sea turtles can be forcibly submerged by longline gear. Forcible submergence may occur
through a hooking or entanglement event, where the turtle is unable to reach the surface to
breathe. This can occur at any time during the set, including the setting and hauling of the gear.
Forced submergence can occur when the sea turtle encounters a line too deep below the surface,
or because the line is too heavy to be brought up to the surface by the swimming sea turtle. For
example, a sea turtle hooked on a 3 meter gangion attached to a mainline set at depth by a 6
meter floatline will generally not be able to swim to the surface unless it has the strength to drag
the mainline approximately 3 more meters (discussed further below). The RPA in the June 14,
2001, opinion specified that gangion length be at least 110% of floatline length on shallow
longline sets. This requirement was intended to reduce or eliminate the threat to turtles presented
in that example situation.
When interacting with longline gear, hooked sea turtles will sometimes drag the clip, attached to
the gangion, along the mainline. If this happens, the potential exists for a turtle to become
entangled in an adjacent gangion which may have another species hooked such as a shark,
swordfish, or tuna. If a turtle were to drag the gangion against another gangion with a live
animal attached, the likelihood of the turtle becoming entangled in the second gangion is greater.
If the turtle becomes entangled in the gear, then the turtle may be prevented from reaching the
surface. The potential also exists, if a turtle drags the gangion next to a float line, the turtle may
wrap itself around the float line and become entangled.
Sea turtles forcibly submerged for extended periods show marked, even severe, metabolic
acidosis as a result of high blood lactate levels. With such increased lactate levels, lactate
recovery times are as long even as 20 hours. Kemp’s ridley turtles stressed from capture in an
experimental trawl (# 7.3 minute forcible submergence) experienced significant blood acidosis,
which originated primarily from non-respiratory (metabolic) sources. Visual observations
4-6

indicated that the average breathing frequency increased from approximately 1-2 breaths/minute
pre-trawl to 11 breaths/minute post-trawl (a 5 to 10-fold increase). Given the magnitude of the
observed acid-base imbalance created by these trawl experiments, complete recovery of
homeostasis may have required 7 to 9 hours (Stabenau et al. 1991). Similar results were reported
for Kemp’s ridleys captured in entanglement nets, where turtles showed significant physiological
disturbance, and post-capture recovery depended greatly on holding protocol (Hoopes et al.
2000).
This long recovery time suggests that turtles would be more susceptible to lethal metabolic
acidosis if they experience multiple captures in a short period of time (in Lutcavage and Lutz
1997). Presumably, a sea turtle recovering from a forced submergence would most likely remain
resting on the surface (given it had the energy stores to do so), which would reduce the likelihood
of being recaptured by a submerged longline. Recapture would also depend on the condition of
the turtle and the intensity of fishing pressure in the area. NOAA Fisheries has no information
on the likelihood of recapture of sea turtles by HMS pelagic longline fisheries. However, turtles
in the Atlantic Ocean have been captured more than once by longliners (on subsequent days), as
observers reported clean hooks already in the jaw of captured turtles. Such multiple captures
were thought to be most likely on three or four trips that had the highest number of interactions
(Hoey 1998).
Stabenau and Vietti (2003) studied the physiological effects of multiple forced submergences in
loggerhead turtles. The initial submergence produced severe and pronounced metabolic and
respiratory acidosis in all turtles. Successive submergences produced significant changes in
blood pH, PCO 2, and lactate, but as the number of submergences increased, the acid-base
imbalances were substantially reduced relative to the imbalance caused by the first submergence.
Increasing the time interval between successive submergences resulted in greater recovery of
blood homeostasis. The authors conclude that as long as sea turtles have an adequate rest
interval at the surface between submergences, their survival potential should not change with
repetitive submergences.
Respiratory and metabolic stress from forcible submergence is also correlated with additional
factors such as size and activity of the sea turtle (including dive limits), water temperature, and
biological and behavioral differences between species. These factors affect the survivability of
an individual turtle. For example, larger sea turtles are capable of longer voluntary dives than
small turtles, so juveniles may be more vulnerable to the stress of forced submergence than
adults. Gregory et al. (1996) found that corticosterone concentrations of captured small
loggerheads were higher than those of large loggerheads captured during the same season.
During the warmer months, routine metabolic rates are higher, so the impacts of the stress from
entanglement or hooking may be magnified (e.g. Gregory et al., 1996). In addition, disease
factors and hormonal status may play a role in anoxic survival during forced submergence. Any
disease that causes a reduction in the blood oxygen transport capacity could severely reduce a sea
turtle’s endurance on a longline. Because thyroid hormones appear to have a role in setting
metabolic rate, they may also play a role in increasing or reducing the survival rate of an
4-7

entangled sea turtle (Lutz and Lutcavage 1997). Turtles necropsied following capture (and
subsequent death) by longliners were found to have pathologic lesions. Two of the seven turtles
(both leatherbacks) had lesions severe enough to cause probable organ dysfunction, although
whether or not the lesions predisposed these turtles to being hooked could not be determined
(Work 2000).
Sea turtles also exhibit dynamic endocrine responses to stress. In male vertebrates, androgen and
glucocorticoid hormones [corticosterone (CORT) in reptiles] can mediate physiological and
behavioral responses to various stimuli, influencing both the success and costs of reproduction.
Typically, the glucocorticoid hormones increase in response to a stressor in the environment,
including interaction with fishing gear. “During reproduction, elevated circulating CORT levels
in response to a stressor can inhibit synthesis of testosterone or other hormones mediating
reproduction, thus leading to a disruption in the physiology or behavior underlying male
reproductive success” (Jessop et al. 2002). A study in Australia examined whether adult male
green turtles decreased CORT or androgen responsiveness to a capture/restraint stressor to
maintain reproduction. Researchers found that migrant breeders, which typically had overall
poor body condition because they were relying on stored energy to maintain reproduction, had
decreased adrenocortical activity in response to a capture/restraint stressor. Smaller males in
poor condition exhibited a pronounced and classic endocrine stress response compared to the
larger males with good body condition. The authors state: “We speculate that the stress-induced
decrease in plasma androgen may function to reduce the temporary expression of reproductive
behaviors until the stressor has abated. Decreased androgen levels, particularly during stress, are
known to reduce the expression of reproductive behavior in other vertebrates, including reptiles.”
Small males with poor body condition that are exposed to stressors during reproduction and
experience shifting hormonal levels may abandon their breeding behavior (Jessop et al., 2002).
Female green turtles have also been studied to evaluate their stress response to capture/restraint.
Studies showed that female green turtles during the breeding season exhibited a limited
adrenocortical stress response when exposed to ecological stressors and when captured and
restrained. Researchers speculate that the apparent adrenocortical modulation could function as a
hormonal tactic to maximize maternal investment in reproductive behavior such as breeding and
nesting (Jessop, et al. 2002).
Although a low percentage of turtles that are captured by longline fishermen actually are reported
dead, sea turtles can drown from being forcibly submerged. Such drowning may be either “wet”
or “dry.” With wet drowning, water enters the lungs, causing damage to the organs and/or
causing asphyxiation, leading to death. In the case of dry drowning, a reflex spasm seals the
lungs from both air and water. Before death due to drowning occurs, sea turtles may become
comatose or unconscious. Studies have shown that sea turtles that are allowed time to stabilize
after being forcibly submerged have a higher survival rate. This depends on the physiological
condition of the turtle (e.g. overall health, age, size), time of last breath, time of submergence,
environmental conditions (e.g. sea surface temperature, wave action, etc.), and the nature of any
sustained injuries at the time of submergence (NRC 1990).
4-8

4.2.6

Mortality at Time of Capture

As stated in the previous subsection, relatively few sea turtles captured on longlines are dead as a
result of injury or forcible submergence when boated or released. Based on the POP database,
only 1.1% of the total number of sea turtles (all species) are dead when brought on board, (see
Table 4.4 –Yeung & Garrison summary). This result does not vary much if the data are separated
into leatherbacks (1.3% dead) and hardshell turtles (1.0% dead). Based on these data, we believe
that turtles are generally hardy enough to survive the initial interaction with longline gear, at least
until released by the vessel’s crew. We further believe that “immediate” mortality is a rare event
occurring with an unusual hooking and/or entanglement or when the turtle’s health is already
compromised by disease or previous injury. We believe that the 1.3% and 1.0% immediate
mortality rates, based on 12 years of observer data from the HMS pelagic longline fishery, are
reasonable values for predicting the outcome of future sea turtle-longline interactions.
4.3 Post-Release Mortality
Even though the vast majority of turtles caught with longline gear are released alive, most or all
of them will have experienced a physiological injury from forced submergence and/or a traumatic
injury from hooking and many may still be carrying penetrating or entangling gear. A number of
studies have attempted to assess the post-release mortality in these turtles. Because of
limitations in the technology or methods of these studies, the application of their results has not
been straight-forward and has generated some controversy, particularly with longline fishermen.
Therefore, NOAA Fisheries has developed post-release mortality criteria, based on the best
available information on the subject, to set standard guidelines for the post-release mortality
estimation.
4.3.1

February 2001 Post-Release Mortality Criteria

In February 2001, NOAA Fisheries established a policy and criteria for estimating sea turtle
survival and mortality following interactions with longline fishing gear (NMFS SEFSC 2001; see
Table 4.3.1). These criteria were based on the information available at the time on the survival
of sea turtles after they were captured and released from longline gear. The June 14, 2001,
opinion applied the February 2001 criteria to the available data on hooking location and
calculated a net post-release mortality rate of up to 22.8% for leatherbacks and 35.6% for
hardshell turtles.

4-9

Table 4.3.1.

Sea turtle mortality rates based on level and type of interaction with longline
fishing gear. Source: NMFS SEFSC 2001

Interaction Type

Release Condition

Injury
Categorization

Mortality Ra te

Entangled / no
hooking

Disentangled

No injury

0%

Disentangled, no gear

Minor

27%

Disentangled, trailing gear

Mod erate

27%

Dehooked, no gear

Minor

27%

Hook left, no gear

Mod erate

27%

Hook left, trailing gear

Serious

42%

Dehooked, no gear

Mod erate

27%

Hook left, no gear

Serious

42%

Hook swallowed

Hook left, trailing gear

Serious

42%

Turtle Retrieved Dead

---

Lethal

100%

Entangled / external
hooking

Hooked in lip (beak)
or mouth

4.3.2

January 2004 Post-Release Mortality Criteria

In 2003, the OPR was charged with conducting a review of NOAA Fisheries’ February 2001
post-hooking mortality criteria and recommending whether or not, and if so, how, the earlier
criteria should be modified. As part of that review, the OPR convened a Workshop on Marine
Turtle Longline Post-Interaction Mortality on January 15-16, 2004. During the workshop, 17
experts in the areas of biology, anatomy, physiology, veterinary medicine, satellite telemetry and
longline gear deployment presented and discussed the more recent data regarding the survival
and mortality of sea turtles subsequent to being hooked by fishing gear. Based on the
information presented and discussed at the workshop, and a comprehensive review of all of the
information available on the issue, the OPR proposed a series of changes and improvements to
the earlier criteria. The new draft criteria are presented in Table 4.3.2. The criteria are still
subject to additional review, but nonetheless constitute the best available science on this topic at
this time.
Interaction Type/Nature of Interaction Categories
The February 2001 interaction type categories were expanded in the new criteria to better
describe the specific nature of the interaction and to reflect the severity of the injury. For
example, the February 2001 criteria described two categories for mouth hooking: (1) hook does
not penetrate internal mouth structure; and (2) mouth hooked (penetrates) or ingested hook. The
new criteria, however, divide the mouth hooking event into three classes: (1) hooked in lower

4-10

jaw (not adnexa); (2) hooked in cervical esophagus, glottis, jaw joint, soft palate, or adnexa1
(insertion point of the hook is visible when viewed through the open mouth); and (3) hooked in
esophagus at or below the heart (insertion point of the hook is not visible when viewed through
the open mouth). The new criteria also separate external hooking from mouth hooking, add a
new category for comatose/resuscitated, and eliminate the February 2001 qualitative injury
categories (no injury, minor, etc.), using only the quantitative percentage rates of mortality to
describe the impact.
Probable Improvement in Survivorship When Gear Is Removed
The new criteria also account for the probable improvement in survivorship resulting from
removal of gear, where appropriate, for each injury. They recognize that in most cases removal
of some or all of the gear (except deeply-ingested hooks) is likely to improve the probability of
survival. The categories for gear removal are: (1) released with hook and with line that is
greater than or equal to half the length of the carapace; (2) released with hook and with line that
is less than or equal to half the length of the carapace; and (3) released with all gear removed.
Turtles that have all or most of the gear removed are expected to have, on average, a higher
probability of survival.
Species Differences
Species differences between hard-shelled turtles and leatherback turtles appear to play a role in
post-release survival. The new criteria take these differences into consideration and assign
slightly higher rates of post-release mortality for leatherback turtles.

1

Subordinate part such as tongue, extraembryonic membranes
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Table 4 .3.2.

Criteria for assessing marine turtle post-interaction mortality after release from longline gear. Percentage rates of mortality are shown for
hardshelled turtles, followed by percentages for leatherbacks (in parentheses).

Nature of Interaction

Released with hook and
with line greater than or
equal to half the length of
the carapace

Release with hook and
with line less than h alf
the length of the
carapace

Released with all gear
removed

Hardshell (Leatherback)

Hardshell (Leatherback)

Hardshell (Leatherback)

Hooked externally with or without entanglement

20 (30)

10 (15)

5 (10)

Hooked in lower jaw (not adnexa 1) with or without
entanglement

30 (40)

20 (30)

10 (15)

Hooked in cervical esophagus, glottis, jaw joint, soft palate, or
adnexa (and the insertion point of the hook is visible when
viewed through the mouth) with or without entanglement

45 (55)

35 (45)

25 (35)

Hook ed in esop hagus at or b elow level o f the heart (includ es all
hooks where the insertion point of the hook is not visible when
viewed through the mouth) with or without entanglement

60 (70)

50 (60)

n/a 2

Entangled Only

Released Entangled
50 (60)
n/a 3

Comatose/resuscitated

Fully Disentangled
1 (2)
70(80)

60(70)

1

Subordinate part such as tongue, extraembryonic membranes

2

Per veterinary recommendation hooks would not be removed if the insertion point of the hook is not visible when viewed through the open mouth.

4-12

4.4 Extent of the Effects – Past Sea Turtle Interactions in the Longline Fishery
Observations of sea turtle bycatch in the pelagic longline component of the swordfish/tuna/shark
fishery number in the thousands. Estimates of the number of turtles taken incidental to the
fisheries in the April 23, 1999, opinion on the HMS fisheries (Scott and Brown 1997) were
revised and updated by estimates provided in Johnson et al. (1999) and Yeung (1999) for NMFS’
June 30, 2000, opinion on the HMS Fisheries. In 1999, the number of turtles incidentally taken
in the HMS fisheries were estimated using a delta lognormal method of preferred pooling order
(quarter, year, area). Total estimated take for loggerheads, over the period 1992 - 1999, was
7,891 (95% CI = 3,835 - 18,805) (See NMFS SEFSC 2001 for full discussion of the method).
Totals for 1999 estimated 991 loggerhead sea turtles incidentally taken (95% CI = 510 - 2,089).
For leatherback sea turtles, an estimated incidental take of 6,363 turtles (95% CI = 2,491 17,613) occurred in the fisheries between 1992-1999. For 1999, an estimated 1,012 leatherbacks
were taken (95% CI = 410 - 2,786). Of these estimated 7,891 loggerhead and 6,363 leatherback
turtles captured by the HMS pelagic longline fisheries from 1992-1999, 66 loggerhead and 88
leatherbacks were estimated to have been released dead (NMFS SEFSC 2001). Of the 991
loggerhead and 1,012 leatherbacks estimated from observer records to have been captured by the
HMS pelagic longline fisheries from 1999, 23 loggerhead were estimated to have been released
dead; there were no leatherbacks released dead that year. These data are important as they were
the latest data available during the previous consultation on the HMS pelagic longline fishery.
Since 1992, green, hawksbill, and Kemp’s ridley sea turtles have been infrequently reported by
the POP. Annual take estimates for these species have ranged from 1 to 87, usually based on the
reported catch of 1 or 2 individuals. More than likely, these are misidentified records of
loggerhead turtle captures (NMFS SEFSC 2001). Loggerhead turtles are the most common hardshelled turtles taken in the fishery (Hoey 1998; Witzell 1999). As observer experience and
training in the POP has improved with time, the reported number of reported green, hawksbill,
and Kemp’s ridley turtles has declined.
Since the June 14, 2001, opinion and the implementation of the HMS pelagic longline closed
areas, a new report of estimated sea turtle takes has been generated for the years 2001 and 2002
(Garrison 2003a). This report updates the previous estimates of interactions in the HMS pelagic
longline fishery. The bycatch estimates for 2002 in this updated report meet the criteria
established in NOAA Fisheries’ report, “National Approach to Standardized Bycatch Monitoring
Programs,” (NMFS 2003) with a coefficient of variation (cv) less than the specified precision
level goal of 20-30% for protected species.
In the most recent report of sea turtle interactions in the HMS pelagic longline fishery, Garrison
(2003a) estimates bycatch of sea turtles by using observer data including those interactions
occurring during the NED experimental fishery. The methodology and approach were similar to
that used in previous assessments of sea turtle interactions in the HMS pelagic longline fishery.
The main difference from the previous assessment by Yeung (1999), which pooled data across
areas to fill empty strata, is that Garrison (2003a) incorporated the mean bycatch rate of
4-13

interactions observed in the quarter-area stratum across the previous five years. This was done
because it is believed that the population sizes of long-lived species, such as marine mammals
and sea turtles, are less likely to undergo large inter-annual fluctuations. Therefore, large interannual differences in bycatch rate are not as important relative to seasonal (quarter) and
geographic (area) effects. No bycatch estimates were incorporated into the analysis when there
was no historical observer coverage information within the previous five years. This approach
avoided the potential biases associated with pooling across geographical strata, while allowing
bycatch estimates for the majority of unobserved strata. However, it should be noted that in the
cases where no bycatch estimate was incorporated, no takes are assumed to occur, and these
strata have been highlighted as potential sources of underestimating bias.
Observed sea turtle captures in the HMS pelagic longline fishery in 2001 and 2002 (Figure 4.4)
illustrate that take was higher than predicted in the June 14, 2001, opinion. Garrison (2003a)
estimated leatherback sea turtle incidental catch in the HMS pelagic longline fishery to have been
1,208 (95% CI = 851-1716) in 2001 and 962 (95% CI = 708-1308) in 2002. Garrison (2003a)
estimated that there were 312 (95% CI = 155-629) loggerhead sea turtles incidentally caught by
the HMS pelagic longline fishery in 2001 and 548 in 2002. Thus, the estimated historical total
number of loggerhead sea turtles caught between 1992-2002, by the U.S. pelagic longline fishery,
is 10,034, of which 81 were estimated to be brought to the vessel already dead (Table 4.4). The
estimated historical total number of leatherback sea turtles caught between 1992-2002, by the
U.S. pelagic longline fishery, is 9,302, of which 121 were estimated to be brought to the vessel
already dead (Table 4.4). This figure does not account for post-release mortalities. The total
number of observed leatherback interactions in 2001, including the NED experiment, was 273.
The total number of observed interactions for 2002, again including the NED experiment, was
335. Interactions in the NED experiment are not shown in Table 4.4.
One loggerhead turtle was observed to have been killed during 2001 and one leatherback was
observed dead during 2002. In 2003, one leatherback sea turtle was observed dead and no
loggerhead sea turtles were observed dead (Garrison, personal communication, 2004). Results
corroborate earlier data that most leatherback sea turtles are hooked externally, typically in the
shoulder or front flipper, whereas loggerhead turtles more often swallowed the hook or were
hooked in the mouth region. In 2001, the highest number of leatherback interactions occurred
during Quarter 3 in the Florida East Coast (FEC) region (254 estimated interactions), and in the
Gulf of Mexico (GOM) statistical area during the 2nd and 3rd quarters (180 and 157 estimated
takes, respectively), with additional high numbers of interactions occurring in the South Atlantic
Bight (SAB) and Mid-Atlantic Bight (MAB) regions. The highest number of loggerhead turtle
interactions occurred during the 3rd quarter in the NEC statistical areas (106 estimated), and 4th
quarter in the NED statistical area (97. Note all takes from the NED are observed, not estimated).
In 2002, the highest number of leatherback sea turtle interactions occurred during the 2nd- 4th
quarters again in the GOM (Garrison 2003a). The estimated number of interactions for the
GOM during 2002 was 694.6. The highest number of loggerhead turtle interactions occurred
during the 2nd quarter in the NEC and GOM statistical areas.

4-14

During the 3-year cooperative research study to develop gear measures for reducing sea turtle
interactions (conducted in the NED statistical sampling area) there were incidental captures of
sea turtles. In the 2001 NED experiment, with 100% observer coverage, there were 186 sets
made by 8 vessels that incidentally caught 142 loggerhead and 77 leatherback sea turtles with no
sea turtles released dead. In 2002, with 100% observer coverage, there were 501 sets made by 13
vessels that incidentally caught 100 loggerhead and 158 leatherback sea turtles. In 2003, there
were 539 sets made by 11 vessels that incidentally caught 92 loggerhead sea turtles, 79
leatherback sea turtles, and 1 olive ridley sea turtle. No sea turtles were released dead in the
NED experiment.

Annual Estimates of Total Marine Turtle Bycatch and the Subset that were Dead
When Released in the U.S. Pelagic Longline Fishery.
Source: NMFS SEFSC 2001 (1992-1999 data); Yeung. 2001 (2000 data);
Garrison, 2003a (2001-2002 data).

Table 4.4.

Species

Loggerhead

Leatherback

Year

Total

Dead*

Total

1992

293

0

914

88

1993

417

9

1,054

1994

1,344

31

1995

2,439

1996

Green

Dead* Total

Haw ksbill

Kemp’s
Ridley

Unidentified

Sum
Total

Dead*

Total

Dead*

Total

Dead*

Total

Dead*

87

30

20

0

1

0

26

0

1,341

0

31

0

31

0

1,533

837

0

33

0

34

0

2,274

0

934

0

40

0

171

0

3,584

917

2

904

0

16

2

2

0

1,839

1997

384

0

308

0

47

0

777

1998

1,106

1

400

0

1

0

1,538

1999

991

23

1,012

0

66

0

2,069

2000

1,256

0

769

0

128

0

2,153

2001

312

13

1,208

0

0

0

1,520

2002

575

2

962

33

50

0

1,587

Total

10,034

81

9,302

121

556

0

20,215

14

221

26

1

33

16

0

17

0

53

0

* Does not account for fishing related mortality that may occur after release.

4-15

22

49

0

0

0

Figure 4.4.

Marine turtle takes during pelagic longline fishing effort during (A)
2001 and (B) 2002. Observed sets with no turtle takes are indicated
by light circles.

4-16

4.5.

Extent of the Effects – Anticipated Future Sea Turtle Interactions

The proposed action would, in part, increase the 2003 North Atlantic swordfish quota from 2,951
mt ww to 3,877 mt ww and increase the quota in2004 and 2005 to 3,907 mt ww. If the increase
in available quota triggers an increase in fishing effort, that would then increase the incidental
catch of protected species. Currently, HMS Division believes it is unlikely that effort will
increase. For the past several years, the level of effort in the HMS pelagic longline fishery has
been steadily declining. Additionally, a number of restrictions, such as limited access and time
and area closures, have been placed on the pelagic longline fleet. This declining effort has led to
under-harvests: despite the existing 2,951 mt ww swordfish quota, only 1,025.4 mt ww was
harvested in the 2001 fishing year. We agree with HMS Division that the level of effort in the
fleet is unlikely to increase despite the change in quota. Therefore, there should not be an
increase in the incidental take of protected species by the HMS pelagic longline fleet.
In the June 14, 2001, opinion, NOAA Fisheries used the sea turtle bycatch estimates from the
most recent year available (1999). Although inter-annual variation in the bycatch estimates has
been high, NOAA Fisheries believes using data from a single, recent year is more likely to be
representative of the level of interactions in future years than using long-term averages. Longterm averages may include underlying changes in the level and distribution of effort, fishing
tactics, and possibly the distribution of sea turtles. For example, HMS pelagic longline fishery
time-area closures went into effect in 2000 and 2001. These closures have changed fishing effort
levels and the distribution of that effort. Therefore, it would be impossible to rely on pre-2002
take estimates for future projections.
In this opinion, we take the same approach, and use the 2002 pelagic longline fishery take
estimates from Garrison (2003a), summarized in section 4.4. We believe this information is
representative of the level of take expected if the status quo were maintained and none of the
proposed rule provisions were enacted. The 2002 data represents the most complete information
available (observer data, but not effort data, are available for 2003), and the fishery is not
expected to significantly change in scope or distribution in the near term. To assess the effects of
reopening the NED, we concur with and rely on the approach used in the DSEIS, which uses the
observed catch per unit effort (CPUE) in the NED experiment and multiplies it by the amount of
effort anticipated to return to the NED.
For the hardshell turtles, other than loggerheads, it is difficult to make predictions about future
levels of interactions. The reported interactions are very low, usually 1 or 2 per year at most, and
often none per year. Also, the existing reports from the POP may include species
misidentifications. Still, we cannot discount the possibility of rare or “out of habitat”
interactions. For example, the NED experiment, with 100% observer coverage, did capture one
confirmed olive ridley and one confirmed Kemp’s ridley in 2003, and other fisheries have had
similar unexpected interactions (e.g., hawksbill turtles in the North Carolina winter trawl fishery
and in the North Carolina fall, estuarine, gillnet fishery). Thus, the observed take of 1 or 2
individuals per year, while not a regular event, would not be surprising. Based on previous
4-17

extrapolation results, this rate would correspond to an estimated take of roughly 35 turtles per
year in the entire HMS pelagic longline fishery .
In this sub-section, we discuss the outcome of the NED experiment and how those results apply
to the future anticipated effects of the action; explain how we chose which results were used to
calculate the anticipated effects; show how the calculations were made and the results of those
calculations; and then calculate and discuss the expected mortality that would be associated with
those takes.
4.5.1

Bycatch Reduction Expected from the Proposed Action

In 2001, the SEFSC launched a cooperative research program to study means to reduce the catch
rates of sea turtles in the HMS pelagic longline fishery and to reduce the mortality of those
captured sea turtles. The research spanned three fishing seasons in the NED, an area with
historically high sea turtle capture rates. These high catch rates offered the opportunity to
generate statistically valid results when testing sea turtle bycatch reduction measures. The NED
experiment was a substantial improvement over previous efforts by NOAA Fisheries to
determine the factors affecting sea turtle catch rates in the HMS pelagic longline fishery.
Previous efforts had relied on post-hoc analyses of observer data that were confounded by the
autocorrelations of the possible factors in the fishery. In contrast, the NED research was a true
experiment that compared experimental versus control treatments within and across sets and used
a rigorous statistical approach to more definitively determine the factors affecting sea turtle
bycatch rates.
The research focused on modifying the actual fishing gear rather than efforts to change the timing
or location of fishing. Gear modification measures are believed to be the most easily and
consistently adopted measures throughout the domestic and international longline fleets and
therefore are expected to achieve the greatest conservation benefit for sea turtles. Although a
number of gear modification measures have potential for bycatch reduction, the SEFSC selected
measures for the NED experiment that appeared to have high bycatch reduction potential and that
could be combined into a single experiment, thus allowing the simultaneous testing of multiple
factors. In the final two years of the experiment, the SEFSC focused its research on terminal gear
characteristics only: hook type, bait type, and their interaction.
Between 2001 and 2003, nine potential mitigation techniques were evaluated during 1,214
research sets, with a total of 1,169,864 hooks fished. Data were collected to evaluate the
effectiveness of the mitigation measures and to investigate variables that affect sea turtle
interaction rates with pelagic longline gear. The results of the research in 2001 indicate that a
significant reduction in loggerhead catch may be achieved by reducing daylight soak time, but in
2002 only total soak time was significant. Blue-dyed squid bait appeared to have no effect on sea
turtle interactions. Moving hooks 20 fathoms away from float lines did not reduce sea turtle
interactions and appeared to have increased leatherback interactions. 18/0 circle hooks and
mackerel bait were both found to significantly reduce loggerhead and leatherback sea turtle
4-18

interactions when compared with industry standard J-hooks and squid bait, but mackerel had no
significant effect over squid when circle hooks were used. Also, circle hooks significantly
reduced the rate of hook ingestion by the loggerheads, reducing the post-hooking mortality
associated with the interactions. The combination of 18/0 circle hooks and mackerel bait was
found to be the most efficient mitigation measure for loggerhead turtles. The relationship was
less clear for leatherback sea turtles, with squid bait and circle hooks showing the highest
reduction rates in some situations (Table 4.5.1). The effect of offset versus non-offset hooks may
play a role in those differences, however, in all cases 18/0 circle hooks provide a substantial
reduction in interactions between sea turtles and longline fishing gear versus J-hooks. Mackerel
bait was found to be more efficient for swordfish than squid bait, and circle hooks were more
efficient for tuna than J-hooks (Watson et al. 2004a, Shah et al. 2004).
In anticipation of the need for mitigation measures in tuna directed fisheries, research was
initiated by NOAA Fisheries late in 2003 comparing 16/0 circle hooks with 18/0 circle hooks.
Only a small number of sets (n=29) could be completed at the time, so the differences could not
be assessed using those data. Information from other studies have shown that there is no
difference in interaction rates between 9/0 J-hooks and 16/0 circle hooks for loggerhead sea
turtles (Bolten et al. 2002; Javitech 2002). Other data (Garrison 2003b) from the observer
program show that no loggerhead turtles have been observed captured on circle hooks in the Gulf
of Mexico (total number of observed circle hook sets = 416). Additionally, it is known that
smaller J-hooks (7/0 and 8/0) are frequently used in the Gulf of Mexico tuna fishery, and are
expected to have a higher catch rate for turtles than the 9/0 J-hook, but the only experimental
data available compares the 16/0 circle hook with the larger 9/0 J-hook (Watson et al. 2004b).
However, despite these caveats, we use the most protective, conservative assumptions in our
analysis, and therefore the take rate for loggerheads on 16/0 circle hooks are considered the same
as that for the 9/0 J-hooks (therefore no take reduction attributed to use of 16/0 circle hooks).
Leatherback interactions are primarily foul hooking, and therefore the use of 16/0 circle hooks
instead of J-hooks is expected to reduce the take of this species. NOAA Fisheries data are
primarily for the 18/0 and 20/0 circle hooks, but there is every reason to believe that a 16/0 circle
hook would be just as effective in reducing leatherback captures by foul hooking, if not more so
(because of the smaller gap between the shank and point) (Watson et al. 2004b). The non-offset
16/0 circle hook with squid is therefore considered to have the same bycatch reduction for
leatherback sea turtles as the non-offset 18/0 circle hook with squid.
HMS Division is now considering, as part of the proposed action, requiring the use of specific
hook and bait combinations in the HMS pelagic longline fishery, based on the results of the NED
experiment and other available information. The allowable hook and bait combinations in the
longline fishery would be:
NED pelagic longline fishery18/0 or larger circle hook with an offset not to exceed 10 degrees. Only mackerel and squid
baits may be possessed and/or utilized with allowable hooks.

4-19

Atlantic/Gulf of Mexico pelagic longline fishery outside of the NED16/0 or larger non-offset circle hooks and/or 18/0 or larger circle hooks with an offset not to
exceed 10 degrees. Only whole finfish and squid baits may be possessed and/or utilized with
allowable hooks.
We expect that these hook and bait combinations will achieve the same levels of sea turtle
bycatch reduction demonstrated in the NED experiment when used throughout the longline
fishery (with the exception of 16/0 circle hooks and loggerheads, as discussed above). For all of
the hooks (except 18/0 non-offset circle hooks for leatherbacks), squid bait is believed to be the
worst-case bait for sea turtle captures. There were significant reductions in both loggerhead and
leatherback catch rates when squid bait was switched for mackerel bait on standard J-hooks.
Additionally, feeding studies involving captive loggerhead turtles show that the turtles usually
attempt to gulp down squid baits whole, taking any hook that may be embedded. When hooks
are baited with fish, a loggerhead usually tears off discrete bites and may be able to scavenge a
fish bait without swallowing or even taking the hook into its mouth. Feeding behavior can also
be impacted by how the hook is baited (e.g. single hooked versus threaded). Garrison (2003b)
reported that use of fish bait resulted in lower turtle capture rates than squid bait, although
numerous other fishing variables were not controlled for. We believe it is a reasonable,
conservative assumption that equivalent circle hooks baited with whole fish will have at least the
same level of sea turtle bycatch reduction as the same circle hooks baited with squid. This is
supported by the reduction percentages shown in Table 4.5.1.
Shah et al. (2004) fitted generalized linear models to investigate the relationship between the
catch rate (or catch probability) and explanatory variables such as hook type, sea surface
temperature, day light soak time, total soak time, vessel effect, and pairing effect in case of
matched-paired hook types per set.

4-20

Table 4.5.1

Sea Turtle Bycatch Reduction Rates for Hook and Bait Combinations. All
reductions are compared to industry standard J-hook and squid bait combination.
Sources: Shah et al. (2004), Watson et al. (2003), Watson et al. (2004a), Bolten et
al. (2002)

Species

Ye
ar

Treatment

Reduction Rate
(%)

Significant Effect
of Year

Loggerhead

20
02

Non-offse t 18/0 circle h ook with sq uid bait

87.5

Yes
(p=0.0002)

Loggerhead

20
03

Non-offse t 18/0 circle h ook with sq uid bait

64.6

Loggerhead

20
02

10 / Offset 18/0 circle hook with macker el bait

90.4

Loggerhead

20
03

10 / Offset 18/0 circle hook with macker el bait

85.8

Loggerhead

N/
A

Non-offse t 16/0 circle h ook with sq uid bait

0

N/A

Leatherback

N/
A

Non-offse t 16/0 circle h ook with sq uid bait

63.9 (est.)

N/A

Leatherback

20
02

10 / Offset 18/0 circle hook with squid ba it

50.0

N/A
(only tested in 2002)

Leatherback

20
02

Non-offse t 18/0 circle h ook with sq uid bait

63.9

Yes
(p=0.0017)

Leatherback

20
03

Non-offse t 18/0 circle h ook with sq uid bait

89.7

Leatherback

20
02

10 / Offset 18/0 circle hook with macker el bait

65.4

Leatherback

20
03

10 / Offset 18/0 circle hook with macker el bait

64.8

No
(p=0.3027)

Yes
(p=0.0258)

A notable aspect of Shah et al.’s results is the significant effect of year on the sea turtle reduction
rates. The same significant effect of year was found for target species catch rates. Because the
reduction rates associated with the hook and bait combinations varied significantly between
years, we do not believe it is appropriate to combine the two years’ results (combined results
were presented in Shah et al. {2004]) when making forecasts about future years. The
significance of year suggests the effect of inter-annual environmental variation or some other
factors not yet understood, which we cannot predict. To be conservative in anticipating a benefit
from the proposed action, therefore, we will base our projections of bycatch reduction for each
species and hook and bait combination on the lower value of the two years.

4-21

The proposed action includes various hook and bait combinations for fishermen to select. We
expect the non-offset hook with squid or finfish combination to be used when targeting tunas
(16/0) or tuna-swordfish mixed (16/0 and/or 18/0), and the 18 /0 offset hook with mackerel
combination to be used when targeting swordfish. We cannot predict with any certainty the
actual mix of hook and bait combinations that will be used in the fishery. In anticipating a
conservative benefit from the proposed action, we will base our projections of bycatch reduction
for each species on the value for the less effective of the two hook and bait combinations. For
leatherbacks we used the bycatch reduction value for the 10 degree offset 18/0 hook with squid
bait in both the NED and non-NED fisheries. This results in a take reduction of 50% compared
to the 2002 bycatch levels using the base configuration of a 9/0 J-hook with squid. For
loggerheads, we used the bycatch reduction value from the non-offset 18/0 hook with squid or
finfish combination for the NED (64.6% reduction) and the 16/0 non-offset circle hook with
squid for the areas outside of the NED (no reduction). For green, hawksbill, Kemp’s ridley and
olive ridley turtles, we have no direct information, but the effects of varying hook type are
probably more similar to loggerheads. Also, because we anticipate, at most, only a few observed
catches of these other hardshell species per year, we are not applying a further bycatch reduction
factor to these rare events, based on the hook and bait types in the proposed action.
4.5.2

Calculation of Anticipated Takes

The next step in determining the effects of the proposed action was to utilize the analyses
described above to calculate the total expected take that would occur on an annual basis if the
proposed action was implemented. Using total estimated take for 2002, a reduction was then
applied based on the proposed hook and bait requirement. The estimated annual take from the
proposed action to reopen the NED was then added to get the total take estimate.
Estimated annual take was calculated separately for 2004 and for the future. A separate estimate
for 2004 was needed because the proposed action would not be implemented, and any reductions
in take resulting from the action, would not occur until the second half of the year. Because
fishing effort is often not uniform throughout the year, Garrison’s (2003) effort data by set was
used to determine what percentage of effort occurred in the first two quarters of 2002 versus the
last two quarters. When adding in the NED take estimates, the entire yearly estimate was added.
The majority of the effort in the NED is expected to take place in the second half of the year, but
the actual percentage of effort that can be expected is unknown. Therefore, we have taken a
conservative approach and added in the total annual estimate for 2004. The NED take estimates
are taken from the DSEIS and were calculated based on the CPUE observed in the NED
experiment with the experimental hook and bait combinations and the amount of annual effort
that the HMS division anticipates to return to the NED.
The total annual take estimation formulas are as follows:
2004 take estimate = (2002 take estimate)(% of effort in 1st two quarters) + (2002 take
estimate)(% of effort in 2nd two quarters)(100% - estimated % reduction from use of circle hooks)
4-22

+ (estimated NED takes per HMS analysis)
2005 and beyond take estimate = (2002 take estimate)(100% - estimated % reduction from use of
circle hooks) + (estimated NED takes per HMS analysis)
The resulting take estimates are:
2004
Leatherback = (962)(49%) + (962)(51%)(100 % - 50%) + 88 = 805
Loggerhead = (575)(49%) + (575)(51%)(100%-0%) + 24 = 599
2005 and beyond
Leatherback = (962)(50%) + 107= 588/year
Loggerhead = (575)(100%) + 60= 635/year
For green, hawksbill, Kemp’s ridley and olive ridley turtles, we anticipate an estimated take of up
to 35 individuals from these four species combined in any year.
4.5.3

Mortality Estimates

To estimate the total impact of the HMS pelagic longline fishery under the proposed action, it is
necessary to estimate the future mortality associated with those takes to better understand the
impact to the species. We utilized the January 2004 post-release mortality ratios presented
earlier in Table 4.3.2, along with sea turtle bycatch and release data from the NED experiment
and non-NED observer data. In some situations, the observer data did not clearly fit into one of
the interaction categories. Following the guidance provided in Epperly and Boggs (2004), those
takes were included in the most conservative category. This captured the highest likelihood of
mortality and the assumption that the take was a deep ingestion. Data for all of these analyses
come from the 2002-2003 fishing season as they are the most recent and complete data available.
Overall mortality ratios are dependent upon both the type of interaction (i.e., where hooked,
entangled or not, comatose or dead upon retrieval) and the gear that was left following the release
(hook remaining, amount of line remaining, entangled or not). Therefore, in addition to how the
turtle interacted with the gear, the experience, ability, and willingness of the crew to remove gear,
and the available gear-removal equipment are very important factors in the post-release mortality
ratios.
4.5.3.1 NED Experiment – Interaction and Gear Removal Results
Observer data from the NED experiments were compiled into the new post-release mortality
categories to determine an overall mortality ratio for J-hooks and circle hooks in those
experiments (Epperly and Boggs 2004). Using J-hooks in the NED experiment (Table
4.5.3.1.A), a total of 147 leatherback and 131 loggerhead sea turtles were captured. Based upon
4-23

the amount of gear that was removed prior to release, and the type of interactions that occurred in
those studies, the overall mortality ratio was calculated to be 0.138 (13.8%) for leatherbacks and
0.330 (33%) for loggerheads. When using circle hooks in the experiment (Table 4.5.3.1.B), a
total of 103 leatherback and 46 loggerheads were captured, with morality ratios of 0.131 (13.1%)
and 0.170 (17%), respectively. The benefit of using circle hooks versus J-hooks was more
evident for loggerheads, where there was a substantial drop in mortality. The mortality benefit to
loggerheads is because circle hooks are more likely to result in mouth hooking and less deep
ingestion than the J-hooks, and that loggerhead sea turtles are known to actively feed on baited
longline hooks. There was little to no mortality benefit to leatherback sea turtles when
interactions occurred because 90% of the interactions, external foul hooking and entanglement,
remain the same regardless of hook type. The NED experiment had 100% observer coverage, as
well as captains and crew that were well trained, well equipped, and experienced in gear removal
from sea turtles. All of this information is based upon 18/0 circle hooks. The use of 16/0 circle
hooks is assumed to result in the same degree of hook removal ability and post-release mortality
as the 18/0 hook. Post hooking mortality is impacted by hooking location, and the 16/0 is known
to hook in similar locations to the 18/0 circle hook (Javitech Ltd. 2002; Watson et al. 2004b).
The mortality ratios attained for circle hooks in the NED experiment represent the best
reasonably expected (under real fishing conditions) mortality ratio for the HMS pelagic longline
fishery under the proposed circle hooks and gear removal equipment requirements.
4.5.3.2 Non-NED Observed Fishery – Interaction and Gear Removal Results
To better understand how the current HMS pelagic longline fishery may be impacting sea turtle
populations, we determined mortality ratios based upon 2002-2003 observer data outside of the
NED experiment, and the post-release mortality guidelines (Table 4.5.3.2). The current HMS
pelagic longline fishery almost exclusively uses J-hooks; therefore, the calculated mortality ratios
assume the use of J-hooks. In observed sets of the non-NED fishery during 2002-2003, a total of
116 leatherback and 95 loggerhead sea turtles were incidentally captured. Based on the observer
data, these takes were separated into the appropriate post-release mortality categories. The
resulting post interaction mortality ratios were 0.319 (31.9%) for leatherback and 0.404 (40.4%)
for loggerhead sea turtles.
It is important to note that the data for the non-NED analysis is based on 12 vessels of which 10
participated in the NED cooperative experiment; thus, NOAA Fisheries believes that this
information may not be representative of the entire fleet. The vessels on which the analysis is
based were not only equipped with all the sea turtle mitigation gear, but also had been trained in
sea turtle mitigation techniques and were supportive of the NED research project objectives to
reduce sea turtle mortality. However, some of the benefit of experienced, well-equipped crews is
countered by the fact that this fishery used J-hooks, which are prone to hooking in manners
resulting in higher mortality than circle hooks. Additionally, a sizeable, but undetermined,
portion of the fishery used relatively small 7/0 and 8/0 J-hooks, which are even more prone to
deep ingestion. In the NED experiment with J-hooks (which only used larger 9/0 hooks) less
than 34% (44 of 131) of loggerhead sea turtles had deeply ingested hooks, while over 47% (45 of
4-24

95) in the non-NED fishery had deeply ingested hooks. There was also a large difference in
leatherback interactions, with 11% (13 of 116) in the non-NED fishery having a deeply ingested
hook (category IV), whereas no deep ingestion occurred for leatherback sea turtles in the NED
experiments despite their use of both J-hook (n=147) and circle hook (n=103). In the non-NED
data, many of the leatherback observations were listed as “unknown if hooked” or “hooking
location unknown.” To be conservative, these were placed into the category IV. In most cases,
they were probably not deeply ingested because that is a very rare occurrence with leatherback
sea turtles; therefore this represents a very conservative overestimate of leatherback post-release
mortality
4.5.3.3 Anticipated Interaction and Gear Removal Rates
To examine the reasonably expected levels of mortality that would occur under the proposed
action, we applied the levels of gear removal that occurred outside of the NED to the data which
best represents the expected interaction types under the proposed rule (the NED circle hook
data). To estimate the level of gear removal that occurs in this fishery, the ratio of gear removal
(hook and line greater than ½ carapace length remaining, etc.) for each interaction type (external,
lower jaw, etc.) was determined for the non-NED observer data. The NED circle hook data were
then redistributed within each interaction category according to the proportion of gear removal
from the non-NED fishery. Again, these results indicate the mortality ratios that could be
expected if circle hooks are used throughout the fishery and gear removal occurs to the degree it
had in the 2002-2003 non-NED fishery. The resulting overall mortality ratios were 0.328
(32.8%) for leatherback sea turtles and 0.218 (21.8%) for loggerhead sea turtles (Table 4.5.3.3).
These values indicate that, compared to the recent non-NED fishery, the mortality levels for
loggerhead sea turtles would drop from 40.4% to 21.8% . This can be attributed to the change
from J-hooks to circle hooks in the fishery. The leatherback mortality ratio would remain
approximately the same as the fishery prior to enactment of the circle hook requirement (32.8%
vs. 31.9% ); again, because the type of interaction does not change as the hook-type changes.
4.5.3.4 Anticipated Lethal Takes
The mortality ratios calculated above were then used to estimate the number of lethal takes
resulting from the fishery under the proposed action by multiplying the estimated total takes by
the mortality ratios. The least conservative approach would be to apply the mortality ratio for the
NED circle hook data. This mortality ratio relies on the fishery being required to use circle
hooks, to have all required gear-removal equipment on board, and to have the experience and
willingness to use the equipment, as was the case in the NED experiment. A more conservative
estimate, which was used for this assessment, is obtained by applying the mortality estimates
based on non-NED removal proportions and NED circle hook interactions. This is based on the
fishery being required to use circle hooks, but removing gear at a rate similar to that occurring
fishery-wide prior to the proposed action. Prior to calculating the post-release mortality,
immediate mortality (dead when brought aboard) must be considered. As explained in section
4.2.6, 1.3% of leatherbacks and 1.0% of hardshell turtles observed in the longline fishery over 12
4-25

years were dead upon gear retrieval. Those percentages are applied to the expected total take for
the purposes of this opinion, although they are probably overestimates because the circle hooks
required in the proposed action are anticipated to decrease immediate mortality. For 2004 only,
where the rule will only be in effect for the second half of the year, the mortality ratios in Table
4.5.3.2 were applied to the take for the first half of the year, with the take for the second half of
the year being treated the same as that for subsequent years.
The 2004 mortality estimates are as follows:
-For leatherback sea turtles, based on estimates of 471 pre-rule takes, 334 post-rule takes, 1.3%
immediate mortality (10 turtles), and the mortality ratios discussed above, the mortality in 2004
is expected to be 266 individuals.
-For loggerhead sea turtles, based on estimates of 282 pre-rule takes, 293 post-rule takes, 1.0%
immediate mortality (6 turtles), and the mortality ratios discussed above, the mortality in 2004 is
expected to be 182 individuals.
For subsequent years, mortality is estimated as follows:
-For leatherback sea turtles, based on 588 total annual takes after the proposed action goes into
effect, 1.3% immediate mortality (8 turtles), and the mortality ratios discussed above, total
annual mortality is expected to be 198 individuals.
-Loggerhead sea turtle annual mortality, based on 635 total annual takes, 1.0% immediate
mortality (6 turtles), and the mortality ratios previously discussed, would be 143 individuals.
For greens, hawksbills, Kemp’s ridleys and olive ridleys, based on 35 total annual takes, and the
mortality rations previously discussed, annual mortality would be up to 8 individuals from these
four species combined in any year.

4-26

Table 4.5.3.1.A. Mortality ratio data for turtles caught on swordfish-style gear using J hooks by NED research fleet in 2002-2003
[based on SEFSC summaries of hooked turtles and estimates of turtles entangled only (not hooked)*]
Released Alive
Hooked with or without entanglement
II. Lower jaw
III. Upper mouth/throat

V. Entangled
only*
IV. Deep
esophagus
Hook & Hook & All gear Hook Hook & All gear Hook & Hook & All gear Hook & Hook & releas- disenline >.5 line <.5 ed en- tangled
line >.5 line <.5 re& line line <.5 reline >.5 line <.5 recp. len. cp. len. moved >.5 cp. cp. len. moved cp. len. cp. len. moved cp. len. cp. len. tangled
len.

I. Externally
Species

Leatherback
Loggerhead
All species

Total

147
131
278

Mortality ratio:
Hardshells
Leatherbacks
Overall Ratio:
Leatherback
Hard shel l**
All species

0.138
0.330
0.228

VI. Comatose
and resuscitated
Hook All gear Dead
& line re<.5 cp. moved
len.

22
0
22

30
0
30

60
17
77

0
0
0

1
0
1

0
2
2

0
0
0

1
36
37

2
30
32

0
0
0

0
44
44

2
0
2

29
2
31

0
0
0

0
0
0

0
0
0

0.20
0.30

0.10
0.15

0.05
0.10

0.30
0.40

0.20
0.30

0.10
0.15

0.45
0.55

0.35
0.45

0.25
0.35

0.60
0.70

0.50
0.60

0.50
0.60

0.01
0.02

0.70
0.80

0.60
0.70

1.00
1.00

0
0
0

0
22
22

1.2
0
1.2

0.58
0.02
0.6

0
0
0

0
0
0

0
0
0

Calculated mortality for each cell in the matrix (no. turtles times mortality ratio)
6.6
4.5
6
0
0.3
0
0
0.45
0.7
0
0
0.85
0
0
0.2
0
12.6
7.5
6.6
4.5
6.85
0
0.3
0.2
0 13.05
8.2

*Estimates of the ratio of entangled only to total takes were obtained from a subsample of sets where all turtles were caught on J hooks.
This ratio was used to estimate entangled only takes from the hooked takes on J hooks from 2002-2003. The ratio of released entangled leatherbacks to
total entangled was 0.05 for all baits and hooks in 2002-2003. This ratio was used to estimate the number of released entangled leatherbacks for J hooks.
No loggerheads were ever released entangled. All other numbers of turtles by categories are totals from the NED observer data as summarized by
Epperly (SEFSC).
**All hardshell turtles assumed to have a mortality ratio like loggerheads, since there were too few NED data on other spp to make direct estimates for
olive ridley or green turtles

4-27

Table 4.5.3.1.B. Mortality ratio data for turtles caught on swordfish-style gear using 18/0 and 20/0 circle hooks by NED research
fleet in 2002-2003 [(based on SEFSC summaries of hooked turtles and estimates of turtles entangled only (not hooked)*]

Species

Leatherback
Loggerhead
All species

Released Alive
Hooked with or without entanglement
I. Externally
II. Lower jaw
III. Upper mouth/throat
Hook & Hook & All gear Hook & Hook & All gear Hook & Hook & All gear
line >.5 line <.5 reline >.5 line <.5 reline >.5 line <.5 recp. len. cp. len. moved cp. len. cp. len. moved cp. len. cp. len. moved

Total

103
46
149

Mortality ratio:
Hardshells
Leatherbacks
Overall Ratio:
Leatherback
Hard shel l**
All species

0.131
0.170
0.143

V. Entangled
IV. Deep esoph.
only*
Hook & Hook & releas- disenline >.5 line <.5 ed en- tangled
cp. len. cp. len. tangled

VI. Comatose
and resuscitated
Hook & All gear
line <.5 recp. len. moved

Dead

7
0
7

20
0
20

32
12
44

0
0
0

0
0
0

1
10
11

0
0
0

1
2
3

8
14
22

0
0
0

0
4
4

2
0
2

32
4
36

0
0
0

0
0
0

0
0
0

0.20
0.30

0.10
0.15

0.05
0.10

0.30
0.40

0.20
0.30

0.10
0.15

0.45
0.55

0.35
0.45

0.25
0.35

0.60
0.70

0.50
0.60

0.50
0.60

0.01
0.02

0.70
0.80

0.60
0.70

1.00
1.00

0
0
0

0
2
2

1.2
0
1.2

0.64
0.04
0.68

0
0
0

0
0
0

0
0
0

Calculated mortality for each cell in the matrix (no. turtles times mortality ratio)
2.1
3
3.2
0
0
0.15
0
0.45
2.8
0
0
0.6
0
0
1
0
0.7
3.5
2.1
3
3.8
0
0
1.15
0
1.15
6.3

*Estimates of the ratio of entangled only to total takes were obtained from a subsample of sets where all turtles were caught on 18/0 and 20/0 circle hooks.
This ratio was used to estimate entangled only takes from the hooked takes on 18/0 and 20/0 circle hooks from 2002-2003. The ratio of released entangled
to total entangled was 0.05 for all baits, and hooks in 2002-2003. This ratio was used to estimate the number of released entangled leatherbacks for 18/0
and 20/0 circle hooks. No loggerheads were ever released entangled. All other numbers of turtles by categories are totals from the NED observer data as
summariz ed by Epperly.
**All hardshell turtles assumed to have a mortality ratio like loggerheads, since there were too few NED data on other spp to make direct estimates for
olive ridley or green turtles

4-28

Table 4.5.3.2. Mortality ratio data for turtles caught on swordfish-style gear (J-hooks) in the non-NED during 2002-2003
(based on SEFSC summaries of observer data)

Species

Leatherback
Loggerhead
All species

Released Alive
Hooked with or without entanglement
I. Externally
II. Lower jaw
III. Upper mouth/throat
Hook & Hook & All gear Hook & Hook & All gear Hook & Hook & All gear
line >.5 line <.5 reline >.5 line <.5 reline >.5 line <.5 recp. len. cp. len. moved cp. len. cp. len. moved cp. len. cp. len. moved

Total

116
95
211

Mortality ratio:
Hardshells
Leatherbacks
Overall Ratio:
Leatherback
Hardshell*
All species

0.319
0.404
0.358

V. Entangled
IV. Deep esoph.
only*
Hook & Hook & releas- disenline >.5 line <.5 ed en- tangled
cp. len. cp. len. tangled

VI. Comatose
and resuscitated
Dead
Hook & All
line <.5 gear
cp. len. removed

46
1
47

34
1
35

7
2
9

0
0
0

0
0
0

0
0
0

2
6
8

0
19
19

0
21
21

11
9
20

2
36
38

9
0
9

3
0
3

0
0
0

0
0
0

2
0
2

0.20
0.30

0.10
0.15

0.05
0.10

0.30
0.40

0.20
0.30

0.10
0.15

0.45
0.55

0.35
0.45

0.25
0.35

0.60
0.70

0.50
0.60

0.50
0.60

0.01
0.02

0.70
0.80

0.60
0.70

1.00
1.00

Calculated mortality for each cell in the matrix (no. turtles times mortality ratio)
13.8
5.1
0.7
0
0
0
1.1
0
0
0.2
0.1
0.1
0
0
0
2.7
6.65
5.25
14
5.2
0.8
0
0
0
3.8
6.65
5.25

7.7
5.4
13.1

1.2
18
19.2

5.4
0
5.4

0.06
0
0.06

0
0
0

0
0
0

2
0
2

*All hardshell turtles assumed to have a mortality ratio like loggerheads, since there were too few NED data on other spp to make direct estimates for
olive ridley or green turtles

4-29

Table 4.5.3.3. Mortality ratio estimates for turtles caught on swordfish-style gear using 18/0 and 20/0 circle hooks based on NED
circle hook bycatch data and non-NED gear-removal ratios.

Species

Released Alive
Hooked with or without entanglement
I. Externally
II. Lower jaw
III. Upper mouth/throat
Hook & Hook & All gear Hook & Hook & All gear Hook & Hook & All gear
line >.5 line <.5 reline >.5 line <.5 reline >.5 line <.5 recp. len. cp. len. moved cp. len. cp. len. moved cp. len. cp. len. moved

Total

Leatherback
Loggerhead
All species

103
46
149

Gear removal ratios:
Leatherback
Loggerhead
Mortality ratio:
Hardshells
Leatherbacks
Overall Ratio:
Leatherback
Hard shel l**
All species

0.328
0.218
0.294

V. Entangled
IV. Deep esoph.
only*
Hook & Hook releas- disenline >.5 & line ed en- tangled
cp. len. <.5 cp. tangled
len.

31
3
34

23
3
26

5
6
11

1
1
2

0
4
4

0
5
5

9
2
11

0
7
7

0
7
7

0
1
1

0
3
3

25
0
25

9
4
13

0.529
0.25

0.391
0.25

0.08
0.5

***
***

***
***

***
***

1.0
0.13

0
0.413

0
0.457

0.841
0.2

0.154
0.8

0.75
0

0.25
1.0

0.20
0.30

0.10
0.15

0.05
0.10

0.30
0.40

0.20
0.30

0.10
0.15

0.45
0.55

0.35
0.45

0.25
0.35

0.60
0.70

0.50
0.60

0.50
0.60

0
0.6
0.6

0
1.5
1.5

15
0
15

Calculated mortality for each cell in the matrix (no. turtles times mortality ratio)
9.3
3.45
0.5
0.4
0
0
4.95
0
0
0.6
0.3
0.3
0.3
0.8
0.5
0.9
2.45
1.75
9.9
3.75
0.8
0.7
0.8
0.5
5.85
2.45
1.75

VI. Comatose
and resuscitated
Hook & All gear
line <.5 recp. len. moved

Dead

0
0
0

0
0
0

0
0
0

0.01
0.02

0.70
0.80

0.60
0.70

1.00
1.00

0.18
0.04
0.22

0
0
0

0
0
0

0
0
0

*Estimates of the ratio of entangled only to total takes were obtained from a subsample of sets where all turtles were caught on 18/0 and 20/0 circle hooks.
This ratio was used to estimate entangled only takes from the hooked takes on 18/0 and 20/0 circle hooks from 2002-2003. The ratio of released entangled
to total entangled was 0.05 for all baits, and hooks in 2002-2003. This ratio was used to estimate the number of released entangled leatherbacks for 18/0
and 20/0 circle hooks. No loggerheads were ever released entangled. All other numbers of turtles by categories are totals from the NED observer data as
summariz ed by Epperly.
**All hardshell turtles assumed to have a mortality ratio like loggerheads, since there were too few NED data on other spp to make direct estimates for
olive ridley or green turtles
***No incidences of lower jaw hooking occurred in the non-NED fishery so a ratio could not be established. A conservative approach was used instead where the ratios from
category III were used, with the rationale that gear removal a category II interaction would be the same difficulty or even easier than category III.

4-30

5.0 CUMULATIVE EFFECTS
Cumulative effects include the effects of future state, tribal, local, or private actions that are
reasonably expected to occur in the action area. Future federal actions that are unrelated to the
proposed action are not considered in this section because they require separate consultation
pursuant to section 7 of the ESA.
Cumulative effects from unrelated, non-federal actions occurring in the northwest Atlantic may
affect sea turtles and their habitats. Stranding data indicate sea turtles in Atlantic waters die of
various natural causes, including cold stunning, as well as human activities, such as incidental
capture in state fisheries, ingestion of or entanglement in debris, ship strikes, and degradation of
nesting habitat. The cause of death of most sea turtles recovered by the stranding network is
unknown.
Most of the fisheries described as occurring within the action area (Status of the Species and
Environmental Baseline), are expected to continue as described into the foreseeable future. Most
of these fisheries will be prosecuted concurrent with the fisheries prosecuted under the Atlantic
Highly Migratory Species Fishery Management Plan and can be expected to continue into the
future. Numerous fisheries in State waters along the Atlantic coast have been known to adversely
affect threatened and endangered sea turtles. The past and present impacts of these fisheries have
been discussed in the Environmental Baseline section of this Opinion. NOAA Fisheries is not
aware of any proposed or anticipated changes in most of these fisheries that would substantially
change the impacts each fishery has on the sea turtles covered by this Opinion.
In addition to fisheries, NOAA Fisheries is not aware of any proposed or anticipated changes in
other human-related actions (e.g. poaching, habitat degradation) or natural conditions (e.g. overabundance of land or sea predators, changes in oceanic conditions, etc.) that would substantially
change the impacts that each threat has on the sea turtles covered by this Opinion. Therefore,
NOAA Fisheries expects that the levels of take of sea turtles described for each of the fisheries and
non-fisheries will continue at similar levels into the foreseeable future.

5-1

6.0 JEOPARDY ANALYSIS: Effect of Action on Likelihood of Survival and Recovery
The analyses conducted in the previous sections of this opinion serve to provide a basis to
determine whether the proposed action would be likely to jeopardize the continued existence of
ESA listed sea turtles known to interact with the fishery. In Section 4, we have outlined how the
interactions with the pelagic longline fishery can affect sea turtles, and the extent of those effects
in terms of annual estimates of numbers of turtles captured and killed. Now we turn to an
assessment of the species’ response to this impact, in terms of overall population effects from the
estimated take, and whether those impacts would appreciably reduce the species’ likelihood of
surviving and recovering in the wild, thereby jeopardizing the continued existence of the species.
6.1 Loggerhead Sea Turtles
As discussed in the status of the species section, five northwestern Atlantic loggerhead
subpopulations have been identified (NMFS SEFSC 2001), with the South Florida nesting and the
northern nesting subpopulations being the most abundant. The TEWG (2000) was able to assess
the status of those two better-studied populations and concluded that the South Florida
subpopulation is increasing, while no trend is evident for the northern subpopulation, which is
thought to be stable. However, more recent analysis, including nesting data through 2003, indicate
that there is no discernable trend over the past 15 years in the South Florida nesting subpopulation
(Witherington pers. comm.). For the three smaller nesting aggregations (Yucatán, Florida
Panhandle, and Dry Tortugas), there are not sufficient or consistent data to determine trends, as
explained in section 3 of this opinion.
Data on the bycatch proportion of loggerheads by subpopulation are not available for the entire
U.S. Atlantic pelagic longline fishery. Previous biological opinions have used estimates based
upon turtle capture on foraging grounds. The application of coastal foraging grounds data
suggested, in the NED, 71-72% of turtles would be from the South Florida nesting aggregation,
17-19% would be from the northern nesting aggregation, and 10-11% would be from the Yucatán
nesting aggregation. However, recent genetic analysis of bycaught loggerheads from the NED
experiment suggests that individuals from the northern Atlantic loggerhead stock and the larger
South Florida Atlantic loggerhead stock are captured roughly in proportion to their population
sizes (LaCasella et al. in press). Further data collection and larger sample sizes from all of the
rookeries are needed before more reliable mixed stock analysis estimates can be achieved.
Although the coastal foraging ground data encompass a wider area, the results of the genetic
analysis from the NED-caught turtles are expected to be more applicable, as the turtles were caught
in the pelagic environment as opposed to coastal habitats, which can be expected to be utilized
differently from the pelagic environment. Additionally, other research has shown that juveniles
appear to return to benthic foraging grounds near their natal beaches after they leave the pelagic
stage (Bowen et al. in review). Therefore, between the findings of LaCasella et al. (in press) and
the fact the longline fishery is widespread throughout the pelagic waters of the Atlantic and Gulf of
Mexico, it is assumed that the overall interaction of loggerhead sea turtles with the pelagic longline
fishery is in proportion with the overall stock sizes of each nesting aggregation. That is, the
6-1

longline fishery is not believed to be affecting any stock disproportionately, which would be a
factor to consider when examining the threat of any individual stock being extirpated.
The individuals taken in the pelagic longline fisheries are pelagic juveniles or juveniles making the
transition between pelagic and benthic modes, but not breeding age adults or even large sub-adults.
All life stages are important to the survival and recovery of the species; however, it is important to
note that individuals of one life stage are not equivalent to those of other life stages. Loggerhead
sea turtles have very long developmental times before reaching maturity (up to 38 years).
Individuals in earlier life stages are subject to many potential sources of mortality, both natural and
human-induced, prior to reaching sexual maturity. The number of individuals in the pelagic
juvenile stage is therefore probably much, much larger than the older stages, because only a small
proportion of individuals survive through the long pelagic juvenile stage to reach sexual maturity.
Only a fraction of pelagic juveniles are ever expected to contribute to the population through
reproduction, and thus are not as valuable to the population as a breeding age adult. The loss of a
certain number of pelagic juveniles, therefore, is less of a threat to the species’ survival and
recovery compared to an equal loss of sexually-mature adults. On the other hand, because the
pelagic juvenile stage has large numbers, the species’ overall population rate of growth (or decline)
can be quite sensitive to changes in survival and mortality rates of the pelagic juvenile stage. In
the absence of information on absolute sizes of the various age classes, however, we cannot
directly convert the anticipated annual mortality of loggerheads from the proposed action,
expressed in number of individuals, into a change in the mortality rate acting on the pelagic
juvenile stage.
In 2001, NOAA Fisheries’ (SEFSC) issued a stock assessment of loggerhead and leatherback sea
turtles that had population assessments for these turtles in the Atlantic (NMFS SEFSC 2001).
These analyses included estimates of the nesting abundance and trends, estimation of vital rates,
population modeling and projections of population status under various scenarios for loggerheads
(there was insufficient data for leatherback modeling), evaluation of genetic relationships between
populations, assessment of the impact of the pelagic longline fishery on leatherbacks and
loggerheads, and evaluation of available data on other anthropogenic effects on these populations.
This document built upon the modeling and analysis presented in the Heppell et al. (2003) chapter
in Bolten and Witherington (2003), which was in press at the time NMFS SEFSC 2001 was
published. The chapter contained a review of loggerhead population modeling and updated the
modeling technique with new information compared to those previously used by Frazer, Crouse,
Crowder, and Heppell. Additionally, the SEFSC document reviews the scientific literature on
previous evaluations of status, trends and biological parameters of Atlantic loggerheads and
leatherbacks. The NMFS’ SEFSC (2001) assessment was reviewed by three independent experts
[Center for Independent Experts (CIE) 2001]. As a result, the SEFSC’ stock assessment report, the
reviews of it and the body of scientific literature upon which these documents were derived,
represent the best available scientific and commercial information for the Atlantic and provide
further analysis for the jeopardy determinations in this opinion.

6-2

The loggerhead population model developed in NMFS SEFSC (2001) was intended to evaluate,
among other things, the effects on overall population growth rates when the survival rate of the
pelagic juvenile stage was varied. This allowed them to model changes in impacts from basinwide longline fisheries. The model was run with three different population growth rates
(population lambda), pre-1990 (before TED use might be expected to confound mortality estimates
from strandings). Those lambdas are 0.95 (from Cape Island, S.C. – the most important nesting
beach for the northern subpopulation – nesting trends [TEWG 2000]), 0.97 (from Cumberland
Island, Georgia – one of the longest continuously monitored nesting sites for the northern
subpopulation – nesting trends [Frazer 1983]), and 1.0 (from the nesting trends meta-analysis of
multiple separate northern subpopulation nesting beaches [NMFS SEFSC 2001 Appendix 1]).
NMFS SEFSC (2001) cautions with respect to the meta-analysis, however, that “it is an
unweighted analysis and does not consider the beaches’ relative contribution to the total nesting
activity of the subpopulation and must be interpreted with some caution.” Additionally, the
lambda=0.95 scenario (a 5% annual decline in population), while the most conservative, is not
supported by other data sets in the region, and much of the Cape Island decline occurred long ago
and may not be indicative of more recent population performance.
The modeling included analyses of three different sex ratios as well, with female offspring
accounting for 35%, 50%, and 80% of the hatchlings. Based upon observed sex ratios and genetic
data of foraging ground populations, the sex ratio for the northern nesting subpopulation was
thought to be skewed towards males, with only 35% of hatchlings being female. The sex ratios for
the South Florida nesting subpopulation was thought to be skewed as high as 80% female. An
ongoing study by Wyneken et al. (2004), however, indicates that the sex ratio issue may not be as
clear as previously thought, but the initial results are preliminary and based on only one year of
sampling, which may not be reflective of long-term conditions. Further research is necessary to
better understand the dynamics of the sex ratios produced by each nesting subpopulation.
The model looked at population level effects of pelagic longline mortality by examining changes in
annual pelagic juvenile survival of +10%, +5%, -5%-, and -10%. The base-case, or status quo,
pelagic juvenile survival rate was solved for assuming a stable age distribution and survival rates
of benthic juvenile and adult stages derived from pre-1990 strandings information. Because
loggerhead turtles are so long-lived, the adult and large benthic juveniles that contributed to the
pre-1990 data set may not have been exposed to pelagic longline fishing when they were pelagic
juveniles, or the fishing effort when they were in that stage had not yet increased to present levels.
It may be, then, that the base-case pelagic juvenile survival in the SEFSC (2001) model is
optimistic, compared to present conditions. The SEFSC report did not attempt to assign a most
likely scenario and certainly did not say that pelagic longline fishing had altered pelagic juvenile
survival by any specified amount. The model is still useful for assessing how large of a change in
survival (increase or decrease) is necessary to produce corresponding population growth or
decline.
The June 14, 2001, opinion concluded that the longline fishery, as then prosecuted, was likely to
jeopardize loggerhead sea turtles. The RPA of that opinion used the NMFS SEFSC (2001) models
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to determine how large a reduction in pelagic mortality was necessary to move the modeled
population from declining to stable or from stable to increasing. Such a population response
would be evidence that the appreciable reduction in likelihood of survival and recovery had been
removed. The RPA determined that a 55% reduction in longline mortality on loggerheads in the
Atlantic was necessary. The RPA also provided measures to achieve that rate of mortality
reduction in the U.S. longline fleet. Calculation of the 55% bycatch mortality reduction target was
based on achieving a positive change in overall pelagic juvenile survival of 10%.
The proposed action continues to achieve the 55% bycatch mortality reduction for loggerheads
from the U.S. fishery, compared to the status quo considered at the time of the 2001 opinion.
Anticipated annual total takes of loggerheads are about a third less (635 vs. 991), and post-hooking
mortality associated with the use of circle hooks instead of J-hooks will be about half as much
(21.8% vs. 40.4% mortality). Therefore, the total loggerhead mortality is expected to be reduced
from over 400 to 143 per year.
In addition, the new TED regulation (published on February 21, 2003 [68 FR 8456]) represents a
significant improvement in the baseline affecting loggerhead sea turtles. Shrimp trawling is
considered to be the largest source of anthropogenic mortality on loggerheads. Because the rule
went into effect only recently, its beneficial effects have not been realized yet. The SEFSC (2001)
model, however, can be used to look at the expected population effect of the new TED regulations.
The model has built in that the effect of introducing fully effective TEDs is a 30% reduction in
total mortality on any life stages small enough to escape through the openings. Based on the
findings of Epperly and Teas (2002), the NMFS SEFSC model assumes that small benthic juvenile
loggerheads (<70 cm) have benefitted from TED requirements since 1990, but that large juveniles
and adults had previously experienced no reduction in total mortality compared to pre-TED days.
It is now expected that the full 30% mortality reduction benefit is being extended to large juvenile
and breeding adult loggerheads. Note, this is not a 30% reduction in shrimp-related mortality, but
a reduction from the total level of mortality from all sources. Epperly et al. (2002) estimated a
94% decrease in shrimp-related mortality for loggerheads in the southeast U.S. as a result of the
new TED rule.
Even assuming that pelagic juvenile survival has already been reduced below the model’s basecase by as much as 10%, the results of the models show that under any sex ratio and an initial
lambda of 0.97 or 1.0 (as explained above, 0.95, even for the northern nesting subpopulation, is
considered to be overly pessimistic and not supported by the most recent data), loggerhead
populations are expected to increase (rather than merely stabilize) with a 10% increase in pelagic
juvenile survivorship. The proposed action is expected to reduce mortality resulting from the U.S.
portion of the pelagic longline fishery by an amount commensurate with what is required of the
international longline fleets to effect a 10% increase in pelagic juvenile survival. Applying the
same standard used in the June 14, 2001, opinion, this reduced impact from the U.S. longline
fishery would be at a level where it would not be expected to contribute to the appreciable
reduction of the likelihood of survival and recovery for loggerhead sea turtles. It is important to
note that although this modeling of the effect of the longline mortality reductions and TED rule
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expansion benefits applies most directly to the northern and South Florida subpopulations, the
same benefits are expected for the other, smaller subpopulations for which there is not enough
nesting data to model. Because the take from the longline fishery is expected to be proportional to
the subpopulations’ sizes, no disparate impact is expected for any of the smaller subpopulations.
Additionally, although there is insufficient data to determine nesting trends, none of the smaller
subpopulations show indications that they are currently in decline. Therefore, the fact that the
modeling predicts positive trends for the larger subpopulations under the various scenarios
indicates that the same should be expected for the smaller subpopulations.
In this opinion’s analysis, we will also look at the actual estimated take and mortality levels of
loggerheads associated with the proposed action, in light of the species’ status and cumulative
effects, and not just examine relative mortality changes in the models. Loggerhead sea turtles are
highly migratory and have the potential to interact with pelagic longline fisheries throughout the
Atlantic basin. An analysis of the international pelagic longline fisheries’ impacts on loggerhead
sea turtles throughout the Atlantic and Mediterranean estimated that the annual take ranged from
210,000-280,000 incidences (Lewison et al. 2004). Using a 40.4% post-interaction mortality
(assuming use of J-hooks and minimal dehooking and gear removal), and the mid-point of the take
range (245,000), it is estimated that 98,989 mortalities occur annually in the international pelagic
longline fishery in the Atlantic and Mediterranean. Of course, there is a great deal of uncertainty
and variability around these basin-wide estimates. Based on the proposed action, the U.S. Atlantic
pelagic longline fleet is expected to take 599 loggerhead sea turtles (182 mortalities) in 2004, and
635 (143 mortalities) annually in subsequent years. This represents only 0.6% of the takes and
0.1% of the estimated mortality (0.2% in 2004) from all of the Atlantic pelagic longline fisheries.
Loggerheads affected by pelagic longline fisheries still have many years, perhaps decades, before
reaching maturity. During this time they experience mortality from numerous natural and human
sources, so we expect that the effect of longline fisheries on loggerhead populations will be
difficult to detect in the only long-running, reliable index of loggerhead abundance – nesting data.
The international pelagic longline fleet has a large estimated annual take for the entire Atlantic
basin. The proposed action would reduce the U.S. contribution to basin-wide longline mortality to
only one-tenth of a percent: if the U.S. fishery did not exist, the difference in overall take would
likely not even be noticeable. Although any level of take and mortality theoretically has a negative
effect on the overlying population, we believe that the take and mortality of loggerheads associated
with the proposed action is not likely to be a detectable adverse effect given that:
•
•
•
•

Interactions are with the pelagic juvenile stage, which is likely the most numerous age class;
Basin-wide interaction levels and mortality are very large;
The U.S. longline fleet represents only 0.1% of the annual loggerhead mortality; and
Although we have concerns about the status of some loggerhead populations in the western
Atlantic due to their failure to recover, the data do not indicate that any of the nesting
subpopulations are currently declining, despite having experienced capture and mortality in
pelagic longline gear for years.

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Therefore, as a result of the above analysis and the various factors considered, we believe that the
takes and resulting mortality of loggerhead turtles associated with the proposed action are not
reasonably expected to cause, directly or indirectly, an appreciable reduction in the likelihood of
either the survival and recovery of loggerhead sea turtles in the wild.
6.2 Other Hardshell Sea Turtle Species
Other hardshell sea turtle species are known to interact with the longline fishery, but only in rare
instances. We anticipate that up to 35 individuals from the combined species, Kemp’s ridley, olive
ridley, green, and hawksbill, may be estimated taken in any year. This level of take would be
predicted to correspond to up to 8 lethal takes per year (through post-release mortality). Because
of the high variability in the observed capture of these species, some years may have no observed
and thus no estimated captures. It is unlikely that any single species of these four will be
consistently impacted year after year. Because of the rarity and intermittence of the interactions,
we believe that the effects of the proposed action are not reasonably expected to cause, directly or
indirectly, an appreciable reduction in the likelihood of survival and recovery of green, hawksbill,
Kemp’s ridley, or olive ridley sea turtles in the wild.
6.3 Leatherback Sea Turtles
The best available stock assessment for evaluating Atlantic leatherback populations is NMFS
SEFSC (2001). That assessment is somewhat confounded by the near absence of data or high
uncertainty for estimates of juvenile and adult survival and mortality, age and growth; and also, by
the intermittence of nesting data from the major leatherback nesting beaches on the north coast of
South America. Nevertheless, a very strong signal of declining nesting was detected for the
nesting aggregation of Suriname and French Guiana, the largest remaining leatherback nesting
aggregation in the world. Nesting there had been declining at about 15% per year since 1987
through the 1990s. From the period 1979-1986, however, the number of nests had been increasing
at about 15% annually. As explained in Section 3, there is a great degree of uncertainty and
inconsistency regarding the leatherback sea turtle population status and trends. The uncertain
trends in nesting at U.S. beaches versus South American beaches complicates our evaluation.
Additionally, because of a lack of sufficient data, the population modeling scenarios performed for
loggerhead sea turtles are not possible at this point for leatherback sea turtles. Therefore, we are
using Spotila et al. (1996) as the latest, most complete estimation of leatherback populations
throughout the Atlantic basin (from all nesting beaches in the Americas, the Caribbean, and West
Africa) (approximately 27,600 nesting females with an estimated range of 20,082-35,133).
In contrast to the situation with loggerheads, which are mostly impacted by longline fishing early
in their development, the leatherbacks captured in the longline fishery are adults and large
juveniles. An exact assessment of the leatherback life stages affected by longlining is hampered by
the animals’ size; it is almost always impossible to bring a captured leatherback safely aboard for
any detailed measurements. Therefore, the POP records leatherback size information based on the
observer’s best estimate of the turtle’s carapace length, to the nearest foot, so the information is not
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very precise. The POP data show that 56% of the leatherbacks are 5' or greater in carapace length.
Average straight carapace lengths of nesting females in St. Croix is about 5' (~150 cm) (Eckert et
al. 1984). Therefore, it appears that at least half of the bycaught leatherbacks are mature breeders,
and the rest are sub-adult animals.
The death of mature breeding females can have an immediate effect on the reproduction of the
species. Sub-lethal effects on adult females may also reduce reproduction by hindering foraging
success, as sufficient energy reserves are probably necessary for producing multiple clutches of
eggs in a breeding year. Additionally, because leatherback sea turtles reach sexual maturity in only
5-15 years, the importance of sub-adults taken in the pelagic longline fisheries is relatively much
higher than for loggerhead sea turtles. According to Spotila et al. (1996), survivorship in the
juvenile/sub-adult stage of leatherback sea turtles is vitally important to the future of the species;
population models are most sensitive to variation in juvenile/sub-adult survival. The number of
individuals in the various stages would also not be as disparate in leatherbacks as in loggerheads.
Because of the duration of the stages and the required, associated survivals (see Spotila et al.
1996), the total number of subabult leatherbacks is probably similar to the total number of adults in
the population, and is certainly within the same order of magnitude. The roughly equal
distribution of subadults and adults in the POP database support this conclusion. Once juvenile
leatherbacks become susceptible to capture in longline gear (whether by size, behavior, or
distribution), we believe susceptibility likely remains relatively constant.
We do not have good information on the sex ratios of the leatherbacks caught in the longline
fishery, or even leatherbacks generally. We assume the population sex ratio is 50%. In their
published leatherback population model, Spotila et al. (1996) also assume a 50% sex ratio.
As with loggerhead sea turtles, leatherbacks are highly migratory and have the potential to interact
with the pelagic longline fishery wherever it is prosecuted in the Atlantic. Throughout the Atlantic
basin, including the Mediterranean Sea, a total of 30,250-70,000 leatherback sea turtles are
estimated to be captured every year by pelagic longline fisheries (Lewison et al. 2004). Using a
middle value from the take range (50,000), a 32.8% post interaction mortality, a 50% sex ratio, and
a 50% adult to juvenile ratio, total annual international longline mortality of adult females is
estimated to be 4,100 per year. According to these calculations, this accounts for approximately
15% of the total 27,600 nesting female population estimated by Spotila et al. (1996) (20,082 35,133).
Under the proposed action, the U.S. pelagic longline fleet is expected to take 805 individuals (266
mortalities) in 2004, and 588 per year (198 mortalities per year) in subsequent years. Using the
same calculations as above for the rest of the fishery, the estimated mortality of breeding-age
females is expected to be 67 in 2004, and 50 per year thereafter. The U.S. fleet would therefore
account for 1.2% of the total longline fishery mortality annually (1.6% in 2004). This is equivalent
to 0.18% (0.14 - 0.24%) of the total nesting female population annually (0.24% [0.19 - 0.33 %] in
2004). Another estimated 50 subadult females per year (67 in 2004) are expected to be killed by
the U.S. fleet as a result of the proposed action. If numbers of adult females and subadult females
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are similar, as we believe, the proportional impact to the subadult stage from the proposed action
would also be similar.
The overall numbers of leatherback takes reported in Lewison et al. (2004) are very high, and the
U.S. contribution appears small relative to the overall pelagic longline fishery in the Atlantic and
Mediterranean. The mortality of adult and subadult leatherbacks – 50 females from each stage,
every year – is not discountable, however. If the mortality were one-time or short-term, there
seems little doubt that a species with a life history like leatherbacks would easily replace the losses
and that level of mortality would not have a noticeable effect on the population. Continued year
after year, as the pelagic longline fishery is expected to continue, however, the loss of 50 adult
females and 50 subadult females, from a population whose adult females number only in the low
tens of thousands, is expected to have appreciable population effects. The loss of the adult females
will directly affect our only population metric – nesting – and will also eliminate those nesters’
immediate contribution to the species reproduction. The fact that similar numbers of subadult
females are also being removed directly reduces the likelihood that the population will replace the
lost adults quickly, as those sub-adults are the exact animals that would recruit to the breeding
population soonest. Continued depressed reproduction from the reduced replacement of the lost
adult females will, in turn, further depress the numbers of hatchlings and juveniles going into the
population that could eventually replace the lost sub-adults. At some point, compensatory effects
(e.g., increased hatching success on the nesting beach as the density of nests declines) may slow or
even stop such a decline, but the population would already be reduced and thus more vulnerable to
extirpation. On the other hand, depensatory effects may also occur with ever smaller populations
(e.g., increased risk of predation to solitary individuals or nests or inability to find a mate) and
further accelerate the decline.
Despite some apparent similarities between the situations with loggerhead and leatherback
mortality in the longline fishery in the Atlantic, there are some notable differences. First, the
leatherback populations are probably smaller than loggerheads. Second, the mortality from the
longline fishery is acting directly on leatherback breeders and soon-to-be breeders, rather than
small juveniles. Third, while the impacts from the U.S. longline fleet are small compared to the
international fleet for both species, the U.S. fleet’s relative contribution to leatherback mortality is
an order of magnitude higher than for loggerheads. At over 1% of the total annual longline
mortality, and annually killing about 0.2% of the estimated number of adult and subadult females
in the population, we believe that the long-term continuation of the proposed action can be
expected to appreciably affect leatherback populations in the Atlantic. Fourth, while we stated that
our concern for loggerheads was lessened by the absence of evidence that the western Atlantic
subpopulations are currently declining, that was based on loggerhead nesting data that is
exponentially more accurate, precise, and longer-term than what is available for leatherbacks. Our
concern for leatherbacks is heightened by the fact that any assessment of the status and trends of
the largest remaining leatherback nesting assemblage in the world is so confused and confounded.
The U.S. longline fishery primarily affects leatherbacks from this assemblage, and the absence of
evidence on the effects on that population is not a reasonable assurance that those effects are not
occurring. Fifth, while we have well-parameterized population models for loggerhead turtles that
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allow us to assess the effects of changes in pelagic and coastal fishery mortality on population
growth rates, we have little or no knowledge of the life history parameters for leatherbacks. We
therefore do not have robust population models with relatively optimistic outlooks, as we do for
loggerheads. Sixth, the beneficial effects of the proposed action for leatherbacks are much less
certain than for loggerheads. The effects of the 16/0 circle hook on leatherback catch rates have
not been measured, but we are assuming they will be the same as observed with the 18/0 circle
hook. With loggerheads on the other hand, the effect of 16/0 circle hooks on hooking location –
and thus post-hooking mortality – has been studied.
We believe that the effects of the proposed action on leatherbacks, considering the species status
and cumulative effects, can be reasonably expected to appreciably reduce the likelihood of the
survival and recovery of leatherbacks in the Atlantic, by reducing their numbers and reproduction.
Taking into consideration the global status of leatherback sea turtles and that the Pacific population
is known to be much smaller than the Atlantic population and is in drastic decline, an action that
appreciably reduces the likelihood of leatherbacks’ survival and recovery in the Atlantic most
certainly reduces the likelihood of the species’ survival and recovery globally.
6.4 Summary
Based upon our review of the best available information, including the effects of the proposed
action, the status of the species, and cumulative effects, we believe that the proposed action is not
likely to reduce appreciably the likelihood of the survival and recovery of loggerhead, green,
hawksbill, Kemp’s ridley, or olive ridley sea turtles in the wild by reducing their reproduction,
numbers, or distribution. Based on the same review, we believe that the proposed action is likely
to reduce appreciably the likelihood of the survival and recovery of leatherback sea turtles in the
wild by reducing their reproduction and numbers.

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7.0 CONCLUSION
We have analyzed the best available scientific and commercial data, the current status of the
species, environmental baseline, effects of the proposed action, and cumulative effects to
determine whether the proposed action is likely to jeopardize the continued existence of any sea
turtle species. In doing so, the analysis focused on the impacts and population response of sea
turtles in the Atlantic Ocean. However, as discussed in section 4.1.1 Scope of the Analysis, the
impact of the effects of the proposed action on the Atlantic populations is directly linked to the
global populations of the species, and the final jeopardy analysis is for the global populations as
listed in the ESA.
Based upon the analyses described above, it is our opinion that long-term continued operation of
the Atlantic pelagic longline fishery, authorized under the Atlantic Highly Migratory Species FMP:
- is not likely to jeopardize the continued existence of loggerhead, green, hawksbill,
Kemp’s ridley, or olive ridley sea turtles; and
- is likely to jeopardize the continued existence of leatherback sea turtles.
Critical habitat has not been designated for these species in the action area; therefore, the
destruction or adverse modification of critical habitat will not occur.

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8.0 Reasonable and Prudent Alternative
This opinion has concluded that the HMS pelagic longline fishery, as proposed, is likely to
jeopardize the continued existence of leatherback sea turtles. The clause “jeopardize the continued
existence of” means “to engage in an action that reasonably would be expected, directly or
indirectly, to reduce appreciably the likelihood of both the survival and recovery of a listed species
in the wild by reducing the reproduction, numbers, or distribution of that species” (50 CFR
§402.02).
Regulations implementing section 7 of the ESA (50 CFR §402.02) define RPAs as alternative
actions, identified during formal consultation, that: (1) can be implemented in a manner consistent
with the intended purpose of the action; (2) can be implemented consistent with the scope of the
action agency's legal authority and jurisdiction; (3) are economically and technologically feasible;
and (4) we believe would avoid the likelihood of jeopardizing the continued existence of listed
species or result in the destruction or adverse modification of critical habitat.
Throughout this opinion, we have recognized that threatened and endangered sea turtles face a risk
of global extinction because of a wide array of human activities and natural phenomena. We
recognize, for example, that the number of turtles killed by foreign longline fleets poses a much
larger and more serious threat to the survival and recovery of sea turtles than U.S. HMS fisheries in
the Atlantic Ocean. Further, this opinion recognizes that sea turtles will not recover without
addressing the full range of human activities and natural phenomena that could cause these animals
to become extinct in the foreseeable future. The existence of these other threats, however, does not
affect NOAA Fisheries’ responsibility to ensure that the proposed action is not likely to jeopardize
the continued existence of leatherback turtles. An RPA that ensures that the HMS pelagic longline
fishery is not likely to jeopardize the continued existence of listed species may not necessarily
ensure that the species will recover in the wild and may not prevent other human activities from
causing their ultimate extinction.
8.1

Specific Elements of the Reasonable and Prudent Alternative

NOAA Fisheries must undertake management and conservation measures to address and reduce
the adverse effects to leatherback populations expected to result from the proposed action.
Specifically, NOAA Fisheries must (1) reduce post-release mortality of leatherbacks, (2) improve
monitoring of the effects of the fishery, (3) confirm the effectiveness of the hook and bait
combinations that are required as part of the proposed action, and (4) take management action to
avoid long-term elevations in leatherback takes or mortality. These measures are necessary to
avoid the likelihood of jeopardy and to authorize the continued prosecution of the HMS pelagic
longline fishery. The RPA is designed to reduce the effects of the HMS pelagic longline fishery to
such a degree that the effects are not likely to appreciably reduce these turtles’ likelihood of
surviving and recovering in the wild. What follows is a single RPA, with four elements, that must
be implemented in its entirety to avoid jeopardizing leatherback sea turtles.

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8.1.1

Maximize Gear Removal to Maximize Post-release Survival

Sea turtle post-release survival is not only dependent on the type of interaction (i.e., where hooked,
entangled or not), but also on the amount of gear left following the release. Removal of some or
all of the gear – except deeply-ingested hooks – is likely to improve the probability of a sea turtle
surviving an interaction event. The January 2004 draft post-release mortality criteria account for
the probable improvement in survivorship resulting from removal of gear, where appropriate, for
each injury. Maximizing gear removal therefore is critical for lowering mortality ratios (see
section 4.3).
In this opinion, our jeopardy conclusion for leatherbacks was based on an estimated 805 takes and
266 mortalities in 2004, and an estimated 588 takes and 198 mortalities in subsequent years,
continuing indefinitely. The post-release mortality ratio used in estimating the anticipated lethal
takes was 32.8%. This post-release mortality ratio was based on the observed fishery’s (non-NED
experiment) gear removal proportions and the NED experiment’s hooking locations with circle
hooks. That post-release mortality ratio, therefore, represents the level of post-release mortality we
expect if the fishery is being required to use circle hooks, and gear removal rates remain the same.
Based on results from the NED experiment, substantial reductions in mortality can be achieved by
maximizing the amount of gear removed from hooked sea turtles. The post-release mortality ratio
for leatherbacks using the NED gear removal proportions and circle hook data was only 13.1%.
The NED experiments had 100% observer coverage and captains and crew that were well trained,
well equipped, and experienced in gear removal from sea turtles. That post-release mortality ratio,
therefore, represents the level of mortality we expect if the fishery is required to use circle hooks
and to have all required gear-removal equipment on board, and has the training, experience, and
willingness to use the equipment.
It is critical that the same level of gear removal achieved in the NED be attained throughout the
fishery. Improving the post-release mortality ratio in the entire HMS pelagic longline fishery to
levels associated with circle hook use in the NED experiment would decrease total leatherback
mortality caused by the fishery by 58%. The NED experience shows that extensive training,
experience, and high motivation are needed to achieve these high rates of success. Therefore,
NOAA Fisheries must provide outreach and training to maximize gear removal and must monitor
the effectiveness of its efforts though the POP.
8.1.1.1 Outreach
NOAA Fisheries must establish a comprehensive outreach program to ensure that fishermen are
aware of the safe handling and gear removal requirements of the proposed action, understand how
to use the required gear, and understand the importance of maximizing gear removal to
maximizing post-release survival of sea turtles. NOAA Fisheries must carry out the following
specific tasks:

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Training materials
HMS Division must develop and distribute training materials on safe handling of sea turtles and
gear removal techniques to all HMS pelagic longline permitted vessels by September 30, 2004.
We believe that video (VHS or DVD) is the most effective training format and the most likely
format to be reviewed by vessel crews. Development and distribution of a training video should be
the first priority for training materials. Additional training materials may include booklets,
laminated placards, etc., and electronic versions of these materials to further enhance availability.
A significant number of participants in the fishery are Vietnamese-Americans or LatinoAmericans. Critical outreach materials must be translated into Vietnamese and Spanish and
distributed to vessels likely to have Vietnamese-speaking or Spanish-speaking crew. Translation
may be time-consuming. Every effort must be made to complete distribution of translated
materials by September 30, 2004. Distribution of translated materials must be completed,
however, no later than November 30, 2004.
Fishery outreach point of contact
NOAA Fisheries possesses technical expertise on longline gear, sea turtle science, and HMS
regulatory requirements in multiple offices. NOAA Fisheries must select a single office, or even
an individual, as the point of contact (POC) for permittees and fishermen with questions on
requirements for safe handling of turtles and gear removal. Point of contact information must be
published in the final rule implementing the sea turtle conservation requirements in the longline
fishery and should be included in the training materials, as appropriate.
The POC will have a critical role in ensuring that fishermen learn the requirements, the techniques,
and the reasons for maximum gear removal. In addition to simply answering fishermen’s
questions, the POC must actively reach out to fishermen to learn about their experiences,
troubleshoot problems, and share solutions and successful experiences with other fishermen and
NOAA Fisheries’ scientists and managers.
Training workshops
NOAA Fisheries must conduct training workshops to explain the final sea turtle conservation
requirements to fishermen. We recommend that the POC conduct the training workshops to
maximize the POC’s overall rapport and effectiveness; however, NOAA Fisheries may design and
staff the training workshops as deemed appropriate. At least three voluntary training workshops
must be given by September 30, 2004: one each in the Gulf of Mexico, the mid-Atlantic, and the
New England regions. Additional workshops beyond the minimum three are encouraged, as are
workshops after September 2004, to ensure the broadest possible contact with affected fishermen.
Outreach through the POP
Pelagic longline observers are the face of NOAA Fisheries to many longline fishermen. Observers
will interact longer and more closely with a greater depth of the fishery participants than any
training workshops, and they will do so under actual fishing conditions where the effectiveness of
the learning can be much greater. The SEFSC must train and require the POP observers to provide

8-3

additional outreach and training to captains and crews on sea turtle safe handling and gear removal
techniques.
At the outset of trips, the observer must offer to review the safe handling and gear removal
techniques with the captain and crew and to provide instruction in the use of the required onboard
equipment. Because the observer’s fundamental role is to document how the fishery is conducted
and its effects on sea turtles, and because the integrity of the data they collect on sea turtle release
condition must be protected if it is to be valid for extrapolations to the overall fishery, observers
may not assist the crew in any way during sea turtle handling and release. Observers may still
handle turtles that have been brought aboard by the crew to carry out permitted scientific tasks
(e.g., attaching standard or telemetry tags, identifying and measuring animals, taking genetic
samples, etc.). During the course of a trip, observers should be encouraged to share with the
captain and crew the turtle handling and gear removal experiences, both successes and problems,
that they have observed. Observers should provide constructive feedback to captain and crew at an
appropriate opportunity after a turtle is captured and released. Before disembarking, the observer
must inspect any sea turtle safe handling and gear removal equipment onboard and record whether
the required gear was available. The SEFSC must include this information in its quarterly reports
(see 8.1.2 below) so that the HMS Division and SERO-PRD can assess the implementation of this
RPA. The information is not intended to be used for enforcement purposes.
The SEFSC must strive to place an observer on each active, permitted longline vessel at least once
over the course of 2004, 2005, and 2006. The Director, SEFSC, may specify the most appropriate
way to implement this requirement to preserve the accuracy of take estimates based on observer
data. If the Director, SEFSC, determines that this requirement cannot be achieved in any form
without seriously compromising the scientific validity of the take estimates, this requirement need
not be implemented. In any event, the SEFSC must include in its quarterly reports (see section
8.1.2 below) the number of unique vessels that were observed. Through 2006, the quarterly report
must also include the cumulative number of unique vessels observed since the effective date of the
final rule implementing the sea turtle conservation requirements and an estimate of the number of
active vessels that have not been observed over the same period.
Maintenance of Outreach Function
NOAA Fisheries must maintain a viable outreach function, beyond the time necessary merely to
accomplish the initial steps identified in this sub-element of the RPA. While demand for training
workshops will likely diminish over time, interaction with fishermen will remain critical for longterm success, and materials may need occasional reproduction or updating based on industry
experiences or new scientific information.

8-4

8.1.1.2 Fisherman Training Certification
The HMS Division must develop and implement a training and certification program to ensure that
the captain of each permitted HMS vessel authorized to fish with pelagic longline gear has
successfully completed training on sea turtle safe handling and gear removal by December 31,
2005. Training must include demonstrations of safe turtle release equipment and protocols and
pelagic longline equipment modifications required under proposed HMS regulations. Training
should also include hands-on instruction, which has proven highly effective in transferring
technical information. Training content must be developed in consultation with the SEFSC. The
certification process must reasonably ensure that the certified individual has actually completed
and understood the training material. The certification process must also include documentation
requirements so that law enforcement officers can readily verify a vessel’s compliance with the
requirement to have a certified captain. Provision must be made for periodic training and
certification opportunities, after 2005, so new captains can receive training.
8.1.1.3 Verification of Maximized Gear Removal
We believe that the outreach and certification requirements specified in this RPA element, along
with experience the fishermen gain with time, will bring the whole fleet up to the high level of gear
removal performance that was seen in the NED experiment. The fleet will receive initial outreach
in 2004, mandatory training and certification in 2005, and will gain experience after that training
throughout 2006. By the beginning of 2007, then, we believe that the fleet will have reached the
maximum performance level seen in the NED experiment.
NOAA Fisheries must monitor the overall expected mortality of sea turtles caught in the longline
fishery, based on their release condition and the January 2004 draft post-release mortality criteria
discussed in section 4.3 above. The SEFSC must instruct POP observers to continue collecting
detailed information on all sea turtle interactions including initial interaction type, hooking
location, amount of gear remaining upon release, and the animal’s condition upon release. The
SEFSC must use this information to determine the net mortality ratio associated with the observed
captures, according to the method of Epperly and Boggs (2004). The net mortality ratio calculated
for leatherbacks and loggerheads3 must be included in the quarterly and annual reports (see section
8.1.2 below).
We have established net mortality ratio targets to ensure that the fleet’s progress in improved sea
turtle handling and gear removal reach the net mortality ratios of 13.1% for leatherbacks and
17.0% for loggerheads by the beginning of 2007 (the long-term targets). These targets are based
on even, annual progress in 2004, 2005, and 2006. The targets are presented in Table 8.1.1.3.

3

This RPA is designed to remove jeopardy for leatherback turtles. Implementing the measures in
this RPA will also benefit loggerhead turtles. Where those benefits affect the anticipated impact on
loggerhead turtles in a quantifiable way, we are including those reduced impacts in the RPA.

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Table 8.1.1.3 Net Mortality Rate Performance Standards
Assumed 3rd & 4th
Quarters, 2004

Target for 1st
Quarter, 2005

Target for 1st
Quarter, 2006

Target for 1st
Quarter, 2007
and onward

Leatherbacks

32.8%

26.2%

19.6%

13.1%

Loggerheads

21.8%

20.2%

18.6%

17.0%

8.1.2

Improve the Accuracy and Timeliness of Reporting and Analysis

The sea turtle take estimates used in our jeopardy analysis are produced from observed bycatch
rates and logbook effort data. Bycatch rates (currently catch per hook) are quantified based on
observer data by geographic area and quarter. The estimated bycatch rate is then multiplied by the
total fishing effort (currently number of hooks) reported in the mandatory logbook to obtain
estimates of the total interactions for sea turtles. Both the accuracy of the data and the timeliness
of its reporting are critical to monitoring the effects of the fishery and assessing whether the RPA
avoids jeopardy for leatherbacks. Observer coverage must be sufficient to produce a statistically
reliable sample of the HMS pelagic longline fishery that accurately represents the entire fishery.
These data must also be available in a timely fashion to monitor the fishery and take corrective
action to avoid long-term elevation of turtle takes beyond those authorized in this opinion. Levels
of observer coverage and timeliness of reporting have been insufficient in the past. Improvement
in the level of observer coverage and within-year and annual reporting are needed.
The June 14, 2001, opinion included terms and conditions concerning observer coverage and
reporting that were intended to ensure that monitoring would: (1) detect adverse effects resulting
from the HMS pelagic longline fishery; (2) assess the actual level of incidental take in comparison
with the anticipated incidental take documented in that opinion; and (3) detect when the level of
anticipated take is exceeded. As in previous consultations, 5 percent observer coverage in the
pelagic longline fishery was required. Observer coverage was required to be distributed according
to a stratified random sampling scheme that would adequately sample the fishery to determine
levels of protected species takes. At a minimum, the regime had to ensure that sampling occurs
annually at a statistically reliable level of coverage within all statistical areas fished. Reporting
requirements included quarterly reports of observed takes and annual reports of estimated takes.
Between 1992 and 2000, the overall average coverage was 4 percent (Beerkircher et al. 2002). The
only time the 5 percent coverage was actually achieved was between 1993 and 1995, when POP
funding was at its highest level. From 1996 to 2000, funding and logistical problems (e.g. not
being able to place observers on all selected trips) resulted in an average of only 3.4 percent
observer coverage, and the 5 percent target level was never achieved in any single year.
In 2001 through 2003, there was 100 percent coverage for the NED experiment which was
technically not part of the fishery authorized in the 2001 opinion. Observer coverage in areas
excluding the NED was only 2 percent during 2001 and overall coverage averaged only 3.7 percent
8-6

for that year. The POP target coverage level was raised to 8 percent in 2002 to meet new ICCAT
targets and to improve the precision of catch and bycatch estimates specified in NOAA Fisheries’
guidelines for fisheries observer coverage levels (NMFS 2003). Overall observer coverage
(including the NED experiment) achieved the new target level in 2002, but was only 3.7 percent
excluding the NED experiment. Thus, a representative cross section of the fishing effort in each
area and during each quarter of the year was not achieved. Reported effort data in 2003 are not
available. Quarterly reports, which estimate the percent coverage obtained based on the previous
year’s reported effort data, estimate overall coverage was 6.3 percent. It is critical that NOAA
Fisheries achieve not only its new target level, but achieve that target level in as many areas and
quarters as possible.
Garrison (2003a) identifies several sources of bias and uncertainty in the take estimates from a lack
of observer coverage in certain statistical fishing areas and quarters. Fishery observer effort is
allocated across 11 large geographic areas and the calendar quarters based on the historical fishing
range of the HMS pelagic longline fishery (see Figure 2.3.1 C). Offshore areas in the SAR, TUN,
and TUS areas have only rarely been included in the POP observer coverage. Bycatch rates for
year-quarter-area strata with greater than 10 reported HMS pelagic longline fishery sets and no
corresponding observer coverage were replaced in the take estimation method with the mean
bycatch rate observed in the quarter-area stratum across the previous five years. For some strata,
there was no observer coverage within the previous five years, thus no bycatch estimates were
made, and turtle catches were assumed to be zero, despite reported fishing effort in those strata.
Applying observer data from previous years is inherently uncertain since bycatch rates can vary
strongly in time and space. The most glaring omission is the generally low current and historical
coverage of the offshore areas including the SAR, TUN, and TUS. It is currently unknown,
therefore, if there are significant interactions with listed species in these sectors of the longline
fishery
Although all of the required quarterly and annual reports have been completed to date, they have
not always been done in a timely fashion. The timeliness of reporting and take analysis are
dependent on the availability of POP observer data and pelagic longline logbook data. Observer
data collected during a fishing trip are entered into a computer usually within seven days upon the
observer’s return to port. Because observers are sometimes still at sea at the end of a quarter, it
takes a minimum of 30 days after the close of each quarter before all the data are available to
complete the quarterly report. Quarterly reports, therefore, are typically completed by the middle
of the subsequent quarter. Because of the work load caused by the 2001-2003 NED Experiment
project, the submission of protected species summary documents by the POP was often greatly
delayed. Annual reports have taken significantly longer to prepare than the quarterly reports and
have sometimes been prepared only every other year. For example, the estimated sea turtle takes in
2001 were presented in the same report as the estimated sea turtle takes in 2002, which was not
completed until December 2003. Annual reports of estimated takes depend on the availability of
observer data, and also on reported effort data. Late logbook forms and quality control procedures
have resulted in final effort data not being available until six-months into the subsequent year.

8-7

Quarterly reports are presently required to include observed take data, the number of sets observed
by statistical area, and an estimate of the observed coverage level. Because the SEFSC does not
compile effort data until the end of the year, however, they have not developed take estimates for
the quarterly reports. Thus, the fishery is ultimately monitored by the annual take estimate reports.
The delay in receiving theses takes estimates caused exceedances of the incidental take level
established in the June 2001 opinion in 2001 and 2002 to go undetected until November 2003.
Had the 2001 take estimates been available in a timely manner, corrective action may have been
taken to avoid exceeding take in 2002.
In our jeopardy analysis, we concluded that the long-term, incidental mortality of 198 leatherback
turtles annually, based on the estimated annual capture of 588 animals, was expected to reduce the
likelihood of leatherback turtles’ survival and recovery in the wild. The first element of this RPA
will, over the next two-and-a-half years, reduce the net post-release mortality for leatherback
turtles by about 60%, and we have specified requirements to monitor this reduction. No measures
are specified, however, in this RPA that further reduce the estimated annual bycatch levels of
leatherbacks beyond the level predicted for the proposed action. Because the basis of our jeopardy
determination – total estimated mortality – is the product of the post-release mortality ratio and the
estimated take levels, we must also ensure that take levels do not become elevated.
In the jeopardy analysis, we stressed that one-time or short-term mortality on leatherbacks, on the
scale of the proposed action’s annual impacts, is not likely to produce any noticeable effect on the
population. Similarly, minor, short-term exceedance of estimated take and mortality levels is not
expected to have noticeably worse population effects, as long as take and mortality do not also
increase on average over the long term. High degrees of variability in natural and anthropogenic
mortality, nesting levels, recruitment success, and the inherent ability of long-lived animals to
withstand short-term impacts require us to focus on long-term, rather than short-term effects,
because of both the biological significance of long-term effects and our likely inability to detect a
population response from short-term impacts.
NOAA Fisheries has issued incidental take for the fishery on an annual basis in the past. Annual
take estimates have high variability, however, because of natural and anthropogenic variation. For
example, leatherback takes over the history of the observer program have ranged from as low as
308 in 1997 to the all time high of 1,208 in 2001. This high variability and the absence of withinyear take monitoring of estimates have prevented HMS Division from being able to detect possible
take exceedance early and pursue corrective action to prevent exceedance of the annual authorized
levels of incidental take.
To ensure that the long-term operation of the fishery does not jeopardize the continued existence of
leatherback turtles, NOAA Fisheries must improve its ability to monitor takes in the fishery and
must be able to take timely corrective action. However, corrective action within any one single
year will likely never be practicable, and minor or short-term exceedance of annual predicted take
levels is not believed to be sufficient to jeopardize leatherbacks. Therefore, this RPA and the
associated ITS will establish a three-year authorized take level for sea turtles. The SEFSC must
8-8

provide timely take information during the course of each three-year period to allow the HMS
Division ample time to detect significant problems in remaining within the authorized take levels
and to take corrective action (e.g., closure of sea turtle interaction hot spots, additional gear
restrictions). We believe a three-year period is the shortest practicable time period for the SEFSC
and the HMS Division to detect and avoid potential long-term take exceedance. We also believe
that three years is sufficiently protective of leatherback turtles: within a reporting period, highly
elevated takes could only theoretically continue for two consecutive years before corrective action
would be taken in the third year to maintain the total take at the authorized annual average level.
Maintaining long-term takes at the average 3-year level considered in this opinion, even though
higher take levels may occur in certain years, will ensure that the effects of elevated takes do not
reduce appreciably the likelihood of leatherbacks’ survival and recovery in the wild.
8.1.2.1 Improve Observer Coverage
The SEFSC must achieve at least 8% observer coverage in the HMS pelagic longline fishery, based
on total annual reported sets. For this RPA, the 8% observer coverage level is a minimum level,
not a target. NOAA Fisheries must provide the POP funding at a level that will ensure the
availability of an observer for any scheduled trip. The SEFSC must adjust the POP’s internal
target number of observed sets to achieve the 8% minimum coverage level, taking into account the
program’s average success rate of observing only 81% percent of the planned sets. The SEFSC
must strive to improve communication between vessel operators and the POP to increase the
POP’s success rate in placing observers on longline trips. The SEFSC must increase efforts to
achieve observer coverage in areas and quarters where sampling has historically been low: by
December 31, 2006, there must be no quarter-area stratum with an assumed sea turtle take of zero
because of lack of current or historic observer coverage and current year reported effort over 30
sets.
8.1.2.2 Improve Observer Data Collection
The different types of hooks and baits authorized for use in the pelagic longline fishery may have
different effects on rates of sea turtle and target species catch (see 8.1.3 below for in-depth
discussion). The POP currently records some information on hooks and bait used on observed
trips. To be able to use POP data to analyze the potential effects of the newly required hooks and
baits, the SEFSC must improve the detail of hook and bait information collected by the POP. The
SEFSC must train and require the POP observers to record not only hook size and brand, but also
amount of hook offset and whether different sizes, brands, and/or offset hooks are used on a given
set. In the case of sets with multiple hook or bait styles, observers must record the proportion of
each hook and bait style used, and if any sea turtles are captured, the exact hook and bait involved.
It is also recommended that exact hook and bait details be recorded for catches of the primary
target species.

8-9

8.1.2.3 Improve Within-Year Monitoring
The SEFSC must improve within-year monitoring to detect high take levels as soon as possible by
improving the existing quarterly reports:
a)
Sea turtle take estimates must be prepared using observer data and preliminary
effort data for that quarter. If preliminary effort data are not available, quarterly
take estimates must be prepared based on effort data from previous years.
b)
Quarterly reports must be submitted to SERO, HMS Division, the Northeast
Regional Office Protected Resources Division, and the Office of Protected
Resources no later than 45 days into the subsequent quarter. In addition to the
information previously provided in the quarterly reports, they must include the
quarterly take estimates specified here, the number of unique vessels observed, the
cumulative number of unique vessels observed since the effective date of the sea
turtle conservation regulations, and the percent of observed vessels that had the
required turtle handling and gear removal results.
c)
Observed takes by statistical area and quarter over the history of the POP must be
reviewed for any notable trends or patterns that can be used to further interpret the
significance of the number of observed takes reported during each quarter. A
summary of that review should be completed by March 31, 2005. Any take
prediction hypotheses stemming from that review must be tested retrospectively
using the 2004 quarterly and annual take estimates. Results should be included in
the 2004 final estimated takes report.
8.1.2.4 Improve Timeliness of Reporting Yearly Take Estimates
The SEFSC must improve the timeliness of reporting yearly sea turtle take estimates by:
a)
Compiling logbook effort data in computer databases and conducting quality
control as logbooks are submitted throughout the year, so that effort data are
available for analysis as soon as possible after the end of the year;
b)
Completing annual take estimates based on observer and effort data by March 15 of
each year;
c)
Subsequently revising the annual estimates by May 31, if quality control of the
effort data for ICCAT purposes results in changes in the effort data; and
d)
Immediately providing these take estimates to SERO, HMS Division, the Northeast
Regional Office Protected Resources Division, and the Office of Protected
Resources.
8.1.3

Confirm Effectiveness of Hook and Bait Combinations

By far the most comprehensive study of the effects of varying hooks and baits on sea turtle bycatch
rates and hooking locations is the NED experiment. The NED experiment conclusively
demonstrated that significant reductions in loggerhead and leatherback catch rates can be achieved
by the use of 18/0 or larger circle hooks or large mackerel bait, instead of the industry-standard J8-10

hooks and squid bait. The NED experiment also demonstrated that an 18/0 or larger circle hook
with a 10/ offset, in combination with mackerel bait, could outfish the industry-standard J-hook
and squid for the target species of swordfish in cold waters, primarily by catching and retaining
larger fish. Thus, in the NED at least, the NED experiment produced a fishing gear solution that
was beneficial to fishermen and sea turtle conservation.
Concerns have been raised, however, about the economic impacts of applying the NED
experiment’s results to other areas or other target species. For example, the 18/0 circle hookmackerel bait combination’s ability to catch larger swordfish may not be realized in other
swordfish grounds, if those larger fish are not available. In addition, a large portion of the U.S.
longline fleet – and probably the large majority of the international longline fleet globally – targets
tunas or a mixture of tunas and swordfish. The effect of the 18/0 or larger circle hook on catch
rates of tuna has not been extensively studied. The smaller 16/0 circle hook is the gear of choice
for tuna-directed fishing in some other fleets (e.g. Canada), and the 16/0 circle hook has been
demonstrated to outfish a 7/0 J-hook (the industry standard in the U.S. Gulf of Mexico tuna
fishery) by 150% (Falterman and Graves 2002). Thus, the 16/0 circle hook is assumed to be an
effective gear choice for tuna-directed fishing. In a limited number of sets in the NED experiment
directly comparing the target-species performance of 16/0 vs. 18/0 circle hooks in tuna-directed
sets, there was no difference in catch rates of yellowfin or bigeye tuna between the two hook sizes,
although the sample size was small. In a more extensive hook and bait comparison in the NED
experiment, the 18/0 circle hooks baited with squid nominally, but not significantly, outperformed
9/0 J-hooks in catch of bigeye tuna, but this was during swordfish directed catch, where the tuna
was only a desirable bycatch
The work of Bolten in the Azores is similar to the NED experiment’s approach and is also
excellent, with controlled hook-type comparisons. Bolten did examine the effect of 16/0 circle
hooks, compared to 9/0 J-hooks, on sea turtle captures and found that the 16/0 hook, either offset
or non-offset, did not reduce captures of loggerheads. Fishing in the Azores, Bolten did not have
high enough leatherback encounter rates to develop any conclusions on effects of 16/0 hooks for
leatherbacks. In the NED experiment, where leatherback encounters were much more frequent,
16/0 circle hooks were not investigated for sea turtle effects, because of Bolten’s earlier negative
results with loggerheads. Watson et al. (2004b) postulate convincingly that the reduction in
leatherback captures seen in the NED experiment with the 18/0 circle hook is the result of the
circle hook’s shape alone and not a function of its size; therefore, the bycatch reduction rate of the
16/0 circle hook should be equivalent to the 18/0 circle hook. We believe that this reasoning is
likely correct, although it has not been empirically demonstrated.
Because of the concern over economic impacts in tuna- and swordfish-directed components of the
longline fishery outside the NED, the proposed action will require the use of 16/0, non-offset, or
18/0 or larger, with up to 10/ offset, circle hooks. The 16/0 hook has been proven to be successful
for tuna-directed fisheries, even though it has not been much used in the U.S. longline fleet, while
the 18/0 hook has not been fully tested. Giving fishermen the option of using the smaller circle
hook is intended to minimize the risk of adverse economic consequences to fishermen, while still
8-11

reducing the catch rate of leatherbacks and the post-release mortality rates of loggerheads. This
rationale depends on two hypotheses that are reasonable and supported by the best available
information, but that have not been scientifically confirmed:
a) Economic impacts to fishermen from required use of the 18/0 or larger circle hook –
demonstrated to reduce both loggerhead and leatherback catch rates – would be severe, compared
to current industry-standard J-hooks, but the economic impacts from required use of the 16/0 circle
hook – demonstrated not to reduce loggerhead catch rates and believed, but not yet demonstrated,
to reduce leatherback catch rates – would be more acceptable; and
b) Leatherback catch rates on 16/0 and 18/0 circle hooks would be equivalent.
Also in this opinion, we have made conservative decisions on the use of offset hooks, even though
the databases to compare the effects of non-offset vs. 10/ offset hooks are small. Additional
research on the effect of offsetting hooks is needed to determine how significant a factor hook
offsets are in turtle catch rates. If 10/offsets can be demonstrated not to increase turtle catch rates
significantly, then our assessment of turtle impacts could be less pessimistic. Also, restrictions on
the use of offset hooks could potentially be eased, improving acceptance of the required circle
hooks by the U.S. longline industry and possibly other fleets as well. On the other hand, if our
conservative decision is confirmed, there would be less question about the necessity of the current
offset restrictions in the proposed action, again, both domestically and internationally.
It is critical to validate these assumptions. NOAA Fisheries must ensure that the long-term
implementation of the proposed action is at least as effective for leatherback take reduction as we
have assumed in this opinion (a 50% reduction compared to U.S. longline industry-standard
practice). In addition, while this opinion focuses on the effects just of the U.S. Atlantic longline
fleet, the sea turtle population impacts from the longline fleets of other nations, both in the Atlantic
and globally, are much more severe than the effects of the U.S. fleet. Convincing other nations to
adopt comparable gear and/or bait modifications to reduce the impacts of the global longline fleets
is essential if there is to be hope of conserving leatherback and loggerhead turtles globally. And
convincing those other nations will likely depend on solid information on target-species catch
effects. As long as uncertainty remains about the economic effects of the use of the 16/0 or the
18/0 circle hook, there is little hope that the international longline fleets will adopt alternate fishing
gear and therefore little hope of achieving significant threat reduction for sea turtles from
international longline gear. NOAA Fisheries must undertake a research project, with an expected
completion date of December 31, 2006, to address these outstanding uncertanties.
8.1.3.1

Evaluation of Leatherback Bycatch

NOAA Fisheries must conduct experiments and/or monitoring of the longline fishery to confirm
whether the assumed bycatch reduction rate of leatherbacks with the use of the 16/0 circle hook is
equivalent to the 18/0 circle hook by:
a)
comparison of the effects of the 16/0 and 18/0 hooks in controlled fishing
experiments, or

8-12

b)
c)

comparison of the effects of the 16/0 hook to the former status quo hooks in
controlled fishing experiments, or
comparison of fishery dependent data.
8.1.3.2

Evaluation of Effect of Offset Circle Hooks

NOAA Fisheries must conduct experiments and/or monitoring of the longline fishery to determine
more precisely the effect of offsets up to 10/ on rates of sea turtle bycatch, hooking location, and
post-release mortality by:
a)
comparison of the effects of the 16/0, non-offset and 16/0, 10/ offset circle hooks in
controlled fishing experiments, or
b)
comparison of the effects of the 18/0, non-offset and 18/0, 10/ offset circle hooks in
controlled fishing experiments.
8.1.3.3

Evaluation of Economic Impacts

NOAA Fisheries must conduct experiments and/or monitoring of the longline fishery to verify the
target species catch effects of the 18/0 circle hook in tuna-directed fishing by either:
a)
comparison of the effects of the 16/0 and 18/0 hooks in controlled fishing
experiments, or
b)
comparison of the effects of the 16/0 hook to the former status quo hooks in
controlled fishing experiments.
8.1.3.4

Principles for Conducting Evaluations

NOAA Fisheries must continue its successful practice of working cooperatively with government
and academic researchers, the U.S. longline industry, and foreign partners to accomplish the
required research effectively, efficiently, and with broad buy-in. The SEFSC, the Southwest
Fisheries Science Center, and the Pacific Islands Fisheries Science Center are the most likely actors
within NOAA Fisheries to carry out these evaluations; they are encouraged to collaborate with
each other and their external partners in developing actual research designs. Separate evaluations
may be combined in individual projects for efficiency. In particular, sea turtle and target species
evaluations may be particularly amenable to combined study.
In selecting among the various alternatives and designing actual experiments, NOAA Fisheries will
be cognizant that some catch rate effects will be difficult to detect because of the low rates of catch
and bycatch in the pelagic longline fishery, and the high variability in those rates. Experiments
looking at negative effects (i.e., intended to support a conclusion that two rates are not different),
in particular, will be carefully statistically designed with an understanding of the power of the test
and an understanding that decisions involving conservation of endangered and threatened species
are to be risk-averse. That is, statistical analysis of sea turtle catch effects shall err on the side of
assuming an adverse effect does exist or a beneficial effect does not exist, rather than the converse.

8-13

Research funded or implemented by NOAA Fisheries may be subject to permit requirements under
the ESA or the MSA. NOAA Fisheries conducts section 7 analyses on the issuance of any such
permits. Some of the research may not require additional authorizations or section 7 analysis,
however, if it would involve fishing with allowed gear (under the requirements of the proposed
action) and interventions with any bycaught sea turtles would be consistent with the proposed
action and the currently authorized operation of the pelagic observer program or any other properly
authorized research program.
8.1.3.5

Application of Evaluation Results

Within 3 months of the completion of each fishing season (i.e., before April 2005, April 2006, and
April 2007), NOAA Fisheries must analyze the results of the previous years' scientific experiment
(or require reporting from government-funded researchers) for the effects of all the tested
parameters on sea turtle and target species catch rates. The research results must be communicated
and coordinated with research partners and other interested parties in a timely manner, so that
continuing research might be adapted or modified appropriately.
HMS Division must evaluate the interim and final research results against the requirements of the
proposed action. HMS Division must consider the possible application of the results through
rulemaking to modify the proposed action, if necessary to reduce sea turtle interactions or improve
fishery economic performance. Because element 2 of this RPA (section 8.1.2) is designed to limit
sea turtle interactions to prevent long-term exceedance of authorized take levels, we do not
perceive a need at this time to mandate application of the evaluation results in any particular way.
We expect, however, that the evaluation results would be critical to HMS being able to take
corrective action that would be minimally disruptive to the fishery, in the event that estimated takes
are projected to exceed the authorized takes.
8.1.4

Take Corrective Action to Prevent Long-Term Elevated Take and Mortality
8.1.4.1 Implement Adaptive Management Strategy to Prevent Exceedance of 3Year ITS

The ITS accompanying this opinion specifies authorized incidental take levels for sea turtles, over
three-year periods, beginning with 2004. The final annual reports of take estimates prepared by the
SEFSC will be the basis for assessing actual vs. authorized takes. During the course of each threeyear period, the HMS Division must review each quarterly and annual report as soon as it becomes
available. If these reports indicate that the fishery is not likely to stay within the authorized threeyear take levels, the HMS Division must take protective/corrective action to avoid long-term
elevations in sea turtle takes and ensure that take levels in the ITS are not exceeded. Such actions
may include time-area closures, additional gear modifications or restrictions, or any other action
deemed appropriate. HMS Division should consider establishing a rule that would allow
implementation of corrective measures through framework action. Such a rule would provide

8-14

industry with greater certainty on the types of management responses that may occur and would
allow for more timely action, reducing the need for later, more drastic action.
8.1.4.2 Reduce Near-Term (2004-2006) Mortality of Leatherbacks by Reducing
Fishery Interactions, If Necessary
The conservation measures in the first and third elements of this RPA will be carried out over the
next two-and-a-half years. The post-release mortality reduction is not expected to be fully
effective until 2007. Likewise, completion of testing that can confirm the effectiveness of the
required hook and bait combinations is not required or likely to be completed before 2007. When
those elements are successfully implemented, after 2006, long-term average annual capture and
mortality of leatherback turtles are expected to be 588 interactions and 84 mortalities, and the
three-year authorized incidental take for leatherback turtles would be 1,764 interactions, with a
corresponding 252 mortalities. In the meantime, however, mortality will be quite a bit higher as
gear removal and post-release survival incrementally improve. Estimated three-year capture and
mortality of leatherbacks for 2004-2006 would be 1,981 interactions and 548 mortalities. The 548
mortalities in 2004-2006 would be more than double the level expected in 2007-2009 and beyond,
and they represent only a 17% reduction in mortalities, compared to the proposed action without
the first element of the RPA. Also, the risk to leatherbacks from the proposed action during this
initial three-year period will be higher, as the effectiveness of the required hook and bait
combinations will not have been confirmed. Therefore, it is particularly important that mortality
rates associated with the fishery not be allowed to exceed the targets laid out in the first element of
the RPA.
The RPA requirements of section 8.1.4.1 will ensure that total leatherback sea turtle takes do not
exceed long-term average take rates, over three year periods. HMS Division may also need to take
additional management action to reduce leatherback mortality in the near-term (2004-2006), while
the other elements of this RPA are being implemented and reaching full effectiveness. Because the
impacts to leatherbacks during the near-term are already expected to be greater than the future
impacts, NOAA Fisheries must monitor post-hooking survival particularly carefully during the
next two-and-a-half years. If fleet-wide gear removal rates are not sufficient to meet the
performance targets in Table 8.1.1.3, HMS Division must take immediate action to offset the
increased mortality rates and bring overall anticipated mortality back down to the level specified in
the first element of the RPA. The proposed action and the first element of this RPA already
include requirements to use circle hooks, known to reduce leatherback bycatch rates, and to
maximize gear removal to maximize post-release survival. Therefore, the only remaining way to
achieve further reductions in leatherback mortality in the pelagic longline fishery would be through
closures that reduce fishing effort in areas of high leatherback bycatch.
Closure of the Gulf of Mexico to Pelagic Longline Fishing
We believe that most closures of small, discrete areas will not produce significant sea turtle catch
reductions because of the relative ease of shifting fishing to nearby areas. For example, HMS
Division analyzed an alternative in their DSEIS to close, year-round, a 25,000 nm2 area in the
8-15

central Gulf of Mexico that accounted for about 41% of the fishery’s total leatherback takes. The
DSEIS estimated, however, that the net reduction in leatherback interactions from that closure
would only be about 16%, because fishermen would simply relocate their effort to other areas
where leatherback interactions would still occur. Following the June 30, 2000, jeopardy opinion,
HMS Division closed an “L-shaped” portion of the NED to reduce sea turtle captures. However,
NMFS SEFSC (2001) analyzed the effects of closing only a limited portion of the NED and found
that interactions were spread throughout the area and not just a small portion. Consequently, HMS
Division’s closure of the NED area, following the June 14, 2001, jeopardy opinion, was a total
closure.
The Gulf of Mexico fishing area in the second and third quarters (April-September) accounted for
fully half of the estimated leatherback bycatch in the longline fishery, based on 2002 observer data.
We believe that a large-scale closure of the Gulf of Mexico during that time is the most effective
available alternative that will significantly reduce fishing effort – and thus turtle interactions – and
likely not simply result in effort displacement. The effect of such a closure would be a 41%
reduction in leatherback interactions, annually, if there is no effort redistribution. Some
redistribution of longline effort would likely occur, but we believe it will be minimized under the
large-area closure scenario. Many Gulf of Mexico-based vessels may convert to other fisheries or
stay idle for a six-month closure.
If fleet-wide gear removal rates are not sufficient to meet the performance targets in Table 8.1.1.3,
HMS Division must immediately implement a closure for the entire Gulf of Mexico (to minimize
redistribution of effort). The timing and duration of the closure must be sufficient to offset,
through reduced interactions, the effects of the higher post-release mortality associated with the
poor gear removal levels, and may be longer or shorter than the six-month closure discussed above.
Substitution of Equally Effective Alternative Closure
HMS Division may substitute an alternative closure or closures to the required Gulf of Mexico
closure, if their analysis shows that the alternative closure(s) would be equally effective at reducing
leatherback sea turtle bycatch, after accounting for redistribution of fishing effort. HMS Division
may consider whether alternative closure formulations would be more desirable because of reduced
socioeconomic impacts, increased bycatch reduction of other species (e.g. loggerhead turtles,
billfish, bluefin tuna, undersize target species), or other relevant factors.
Removal of Closure Requirement
The time-area closure(s) may be removed when data collected on gear removal and post-release
survival show that fleet-wide interaction types and gear removal rates have met the post-release
mortality targets. With successful implementation of the other elements of this RPA, those criteria
should be met by early 2007. If they are not met, the closure(s) must remain in effect until they
are.
Corrective Action to Achieve Post-Release Survival Targets

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If the 2005 and 2006 targets (Table 8.1.1.3) are not achieved, in addition to the closure discussed
above, HMS Division must consult with the SEFSC to determine whether there are identifiable
problems in training, compliance in the fishery, effectiveness of the circle hooks, or effectiveness
of the gear removal tools and techniques. HMS Division must then take corrective action, as
appropriate, to ensure that the long-term targets are successfully achieved. If HMS Division and
SEFSC determine that the long-term target for leatherbacks cannot be achieved because of some
unseen circumstance, HMS Division must determine whether and how it intends to proceed with
the continued authorization of the fishery in light of the requirement to avoid jeopardizing the
continued existence of leatherback turtles, and inform SERO of its intended course of action.
8.2 Effect of the Reasonable and Prudent Alternative
This RPA includes requirements intended to reduce post-release mortality of sea turtles, improve
monitoring of the effects of the fishery, confirm the effectiveness of the hook and bait
combinations that are required as part of the proposed action, and take management action to avoid
long-term elevations in sea turtle takes. The RPA is designed to reduce the effects of the HMS
pelagic longline fishery to a level where they are not likely to appreciably reduce the leatherback
sea turtle’s likelihood of surviving and recovering in the wild. The measures in the RPA will also
necessarily affect the impacts of the action on loggerhead and other hardshell turtles, which were
not found likely to be jeopardized by the proposed action. In this sub-section, we will briefly
summarize the effects of the proposed action, as modified by the RPA, on all affected species of
sea turtles. Then we will specifically evaluate the population effects to leatherback turtles to
ensure that the RPA will remove the action’s appreciable reduction of the leatherback’s likelihood
of survival and recovery.
Section 4 of this document explained the anticipated annual take levels and the status quo
anticipated post-release mortality rates for each sea turtle species. The first element of the RPA
provides measures to minimize post-release mortality over a two-and-a-half year period. The
second element of the RPA requires improvements in the monitoring of the fishery’s effects. The
third element of the RPA requires NOAA Fisheries to undertake a comprehensive research
program to confirm the presumed effects of the required hook and bait types. The fourth element
of the RPA requires the HMS Division to ensure long-term average take rates are not exceeded.
The fourth element also requires careful monitoring of the progress the fishery makes towards
maximum gear removal and conditionally requires the closure of the Gulf of Mexico area (or an
equivalent alternative) for a period necessary to offset the mortality effects if the fishery does not
meet the necessary post-release mortality reduction targets. Table 8.2 summarizes the anticipated
take levels and associated mortality based on implementation of the RPA and contrasts it with the
mortality associated with the proposed action without the RPA (shown in parentheses). Because
the Gulf of Mexico closure is conditional, Table 8.2 does not reflect the effect of a closure in the
take levels. The purpose and effect of such a closure would be to reduce the total number of
captures and maintain the total estimated mortality.

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Table 8.2 Anticipated triennial incidental takes and mortality of listed species in the longline
fishery with implementation of the RPA. Total estimated mortality without the RPA is shown in
parentheses.
Total
Captures

Post-Release Mortality

Total Estimated
Mortality

2004-2006

1981

32.8% in 2004,
declining to 26.2% in 2005,
declining to 19.6% in 2006

548 (662)

2007-2009,
2010-2012...

1764

13.1%

252 (594)

2004-2006

1869

40.3% in 1st & 2nd Qtrs 2004,
declining to 20.2% in 2005,
declining to 18.6% in 2006

438 (468)

2007-2009,
2010-2012...

1905

17.0%

339 (429)

2004-2006

105

40.3% in 1st & 2nd Qtrs 2004,
declining to 20.2% in 2005,
declining to 18.6% in 2006

25 (25)

2007-2009,
2010-2012...

105

17.0%

18 (21)

Species

Time Period

Leatherback

Loggerhead

Other
hardshells

Long-term mortality under the RPA is reduced by 21% for loggerhead turtles and by 15% for the
other hardshell species. Because we found in the jeopardy analysis that the mortality of
loggerhead, green, Kemp’s ridley, hawksbill, and olive ridley turtles under the proposed action is
not likely to jeopardize the continued existence of those species, we reach the same conclusion for
the reduced level of mortality under the RPA.
Leatherbacks receive even greater benefits from the RPA in reduced total mortality, both over time
and compared to the proposed action. In the near-term, 2004-2006, the RPA reduces total
estimated mortality by 17% for leatherback turtles. The gains that can be made in the near-term are
limited, because 2004 will be at least halfway over before the benefits from the required use of
circle hooks will begin to accrue, and because we expect that the benefits from improved sea turtle
handling and gear removal will take two-and-a-half years to fully materialize. Long-term, the
benefits to leatherbacks from the RPA will be large: a 58% in mortality compared to the proposed
action without the RPA.
Our jeopardy analysis for leatherback turtles focused on the action’s effects on females. We expect
that the effects on males would be the same as on females, with an assumed 50:50 sex ratio and no
reason to believe that there is a sex-selectivity in pelagic longline captures of leatherbacks. Female
8-18

turtles were critical to our analysis, however, as their numbers are most measurable as nesters and
their survival more directly affects the species’ reproduction. In the analysis, we stated that, “If the
mortality were one-time or short-term,... [it] would not have a noticeable effect on the population.
Continued year after year..., however, the loss of 50 adult females and 50 subadult females, from a
population whose adult females number only in the low tens of thousands, is expected to have
appreciable population effects.” We also highlighted a number of concerns resulting from aspects
of the species’ biology, the impacted segments of the population, and the scientific uncertainty
about the species’ status, the species’ life history, and the effectiveness of the hook and bait
combinations in the proposed action.
With implementation of the first element of the RPA, continued prosecution of the longline fishery
is expected to result, long-term, in mortality of only 21 adult and 21 subadult females annually.
This reduced level of mortality represents only 0.5% of the total leatherback mortality from pelagic
longline fleets in the Atlantic and the Mediterranean and less than 0.1% of the estimated adult
female leatherback population in the Atlantic. In addition, the second and fourth elements of the
RPA will ensure that the fishery’s effects will not exceed the predicted take levels for three-year
periods. Previous monitoring and management of the HMS pelagic longline fishery had allowed
significant increases in interactions to go undetected and/or uncorrected for extended periods,
increasing the risk posed to leatherback populations. The third element of the RPA further reduces
the risk to leatherback populations associated with the proposed action by more definitively
confirming the effects of hook and bait combinations and the implications of the sea turtle
conservation rulemakings. The third element is also expected to have important conservation
implications for sea turtles, beyond just the RPA, by improving the scientific and management
arguments available to convince other nations – whose sea turtle impacts are much larger than the
HMS pelagic longline fleet’s – to adopt hook and bait requirements for sea turtle conservation.
The fourth element also provides an important check on the effectiveness of the first element by
requiring that closures be implemented if the post-release survival gains are not achieved in a
timely manner. Our jeopardy analysis did state that one-year or short-term mortality – at the level
of the proposed action – would not have a noticeable population effect, but we were aware that it
would be part of a continuing action. Therefore, during the near-term period when mortality will
be higher than the long-term target for the RPA, but below the level of the proposed action without
the RPA, the fourth element assures that mortality will be tightly controlled and not allowed to
exceed the near-term targets. With the near-term risks controlled and long-term annual leatherback
mortality reduced to exceedingly low levels, compared to the overall mortality (half-a-percent of
longline mortality in the basin) and the population’s size (less than a tenth of a percent), we believe
that the effects of these losses will be below the threshold where they would produce a detectable
change in Atlantic leatherback populations. Taken together, the elements of the RPA are expected
to reduce the threat posed by the HMS pelagic longline fishery to leatherback sea turtles to a level
where it is unlikely that the proposed action would appreciably reduce the likelihood of the
species’ survival and recovery. Therefore, we conclude that – if NOAA Fisheries fully implements
all of the elements of this RPA – the long-term continued operation of the Atlantic pelagic longline
fishery is not likely to jeopardize the continued existence of leatherback sea turtles.

8-19

9.0 Incidental Take Statement
Section 9 of the ESA and protective regulations pursuant to section 4(d) of the ESA prohibit the
take of endangered and threatened species, respectively, without a special exemption. Take is
defined as to harass, harm, pursue, hunt, shoot, wound, kill, trap, capture or collect, or attempt to
engage in any such conduct. Incidental take is defined as take that is incidental to, and not the
purpose of, the carrying out of an otherwise lawful activity. Under the terms of section 7(b)(4) and
section 7(o)(2), taking that is incidental to and not intended as part of the agency action is not
considered to be prohibited taking under the ESA provided that such taking is in compliance with
the reasonable and prudent measures and terms and conditions of the ITS.
Section 7(b)(4)(c) of the ESA specifies that in order to provide an incidental take statement for an
endangered or threatened species of marine mammal, the taking must be authorized under section
101(a)(5) of the MMPA. Since no incidental take of listed marine mammals is expected or has
been authorized under section 101(a)(5) of the MMPA, no statement on incidental take of
endangered whales is provided and no take is authorized. Nevertheless, the HMS Division must
immediately (within 24 hours, if communication is possible) notify the NOAA Fisheries’ Office of
Protected Resources should a take of an endangered whale occur.
9.1 Amount or extent of take
We believe that the levels of incidental take shown in Table 9.1 may be expected to occur as a
result of the proposed action and the implementation of the RPA. These numbers represent the
total takes over three-year periods, beginning with 2004. Total annual takes in the fishery are
estimated by the SEFSC based on their pelagic observer program, the NED experiment results, and
reported fishing effort. The reasonable and prudent measures specified in this ITS, with their
implementing terms and conditions, are designed to minimize the impact of incidental take that
might otherwise result from the proposed action. If, during the course of the action, this level of
incidental take is exceeded, such incidental take represents new information requiring reinitiation
of consultation and review of the reasonable and prudent measures provided. The HMS Division
must immediately reinitiate formal consultation, providing an explanation of the causes of the take
exceedance, and review with the SERO PRD the need for possible modification of the reasonable
and prudent measures (50 CFR 402.16). The RPA contains specific requirements to prevent the
incidental take levels from being exceeded, so take exceedance should only occur under
exceptional circumstances.

9-1

Table 9.1 Anticipated incidental takes of listed species in the longline fishery
Species

Number Captured
from 2004-2006

Number Captured
each Subsequent 3-Year
Period

Leatherback turtle

1981

1764

Loggerhead turtle

1869

1905

Green, Hawksbill, Kemp’s ridley,
and Olive Ridley turtle, in
combination

105

105

9.2 Effect of the Take
NOAA Fisheries has determined that the level of anticipated take specified in Table 9.1 is not
likely to result in jeopardy to the green, hawksbill, Kemp’s ridley, olive ridley, or loggerhead sea
turtle. This level of take is also not likely to result in jeopardy to leatherback sea turtles when the
RPA specified in section 8 is enacted, and the following reasonable and prudent measures are fully
implemented. The RPA reduces the level of mortality affecting captured sea turtles, improves
monitoring and reporting, requires management action to avoid long-term elevations in sea turtle
takes, and confirms the effectiveness of hook and bait combinations.
9.3 Reasonable and Prudent Measures
Section 7(b)(4) of the ESA requires that, when an agency action is found to comply with section
7(a)(2) of the ESA and the proposed action may incidentally take individuals of listed species,
NOAA Fisheries will issue a statement specifying the impact of any incidental taking. It also states
that reasonable and prudent measures necessary to minimize impacts, and terms and conditions to
implement those measures be provided and must be followed to minimize those impacts. Only
incidental taking by the federal agency or applicant that complies with the specified terms and
conditions is authorized.
The reasonable and prudent measures and terms and conditions are specified as required by 50
CFR § 402.14 (i)(1)(ii) and (iv) to document the incidental take by the HMS pelagic longline
fishery and to minimize the impact of that take on sea turtles. These measures and terms and
conditions are non-discretionary, and must be implemented by NOAA Fisheries in order for the
protection of section 7(o)(2) to apply. NOAA Fisheries has a continuing duty to regulate the
activity covered by this incidental take statement. If NOAA Fisheries fails to adhere to the terms
and conditions of the incidental take statement through enforceable terms, and/or fails to retain
oversight to ensure compliance with these terms and conditions, the protective coverage of section
7(o)(2) may lapse. In order to monitor the impact of the incidental take, the HMS Division must
report the progress of the action and its impact on the species to NOAA Fisheries as specified in
the incidental take statement [50 CFR 402.14(i)(3)].
9-2

We note that the HMS pelagic longline fishery has been the subject of several previous biological
opinions which have specified their own reasonable and prudent measures to monitor and
minimize the impacts of incidental take. Most of those reasonable and prudent measures have
been permanently implemented by NOAA Fisheries through regulations or as standard operating
procedures. In addition, the purpose of HMS Division’s February 11, 2004, proposed rule is to
reduce the bycatch rates and bycatch mortality of sea turtles in the pelagic longline fishery. Thus,
the proposed action already includes many measures to monitor and minimize the impact of the
longline fishery’s incidental take of sea turtles. Further, the RPA in this opinion contains
additional sea turtle conservation measures, necessary to remove jeopardy to leatherback sea
turtles, that also monitor and minimize the impact of the proposed action’s incidental take of sea
turtles. We believe the following reasonable and prudent measures are necessary and appropriate
to monitor and minimize the effect of take of listed species considered in this opinion:
a) NOAA Fisheries must improve the understanding of leatherback sea turtle life history and
population status and provide updated information to be used in management decisions
b) NOAA Fisheries must continue efforts to better understand sea turtle post-release mortality
rates and the factors affecting these rates.
c) NOAA Fisheries must take action to ensure improved compliance with safe handling and
release gear required on board.
d) NOAA Fisheries must improve the HMS pelagic longline fishery’s compliance with vessel
safety requirements to reduce the number of inadequate or unsafe vessels for purposes of
carrying an observer and for allowing operation of normal observer function vessels in the
fleet.
9.4 Terms and Conditions
In order to be exempt from the prohibitions of section 9 of the ESA, NOAA Fisheries must comply
with the following terms and conditions, which implement the reasonable and prudent measures
described above and outline required reporting/monitoring requirements. These terms and
conditions are non-discretionary.
a) Convene an expert working group on leatherback sea turtles. By December 31, 2004, NOAA
Fisheries must select and assemble a group of population biologists, sea turtle scientists, and
life history specialists, and natural resource managers who are known experts on sea turtle
conservation issues, especially for leatherback sea turtles. These experts may come from
academic, government, industry, and/or non-profit organization backgrounds. This group will
be charged with compiling the best, most up-to-date information on leatherback sea turtle life
history, ecology, population status, and threats. The information is then to be synthesized and
presented in a NOAA technical memorandum to be used as a reference on the ecology and
9-3

status of leatherback sea turtles in the Atlantic and to provide information to be used in making
sound management and conservation decisions.
b) Leatherback research plan. NOAA Fisheries must develop and implement a research plan to
obtain the necessary demographic data to conduct stock assessment analysis and determine the
status of the Atlantic leatherback sea turtle. These include, but are not limited to survivorship
in each life history stage, age and growth, age and size at stage, age and size at maturity,
fecundity and the associated variability of each, and recruitment and dispersal.
c) Finalize post-release mortality criteria. OPR must issue final post-release mortality criteria by
December 31, 2004.
d) Post-release mortality studies. NOAA Fisheries must initiate a full study of post-hooking
mortality of loggerheads based on the results of the pilot study conducted in the NED and begin
a pilot study for leatherbacks. NOAA Fisheries has demonstrated the ability to capture control
(fishery independent) and treatment (fishery dependent) loggerheads, and should now
implement a full study in order to attain an appropriate sample size to compare survival
between the two groups. A similar study should be initiated for leatherbacks as well. Results
of these studies would refine post-hooking mortality estimates currently used by the OPR.
e) Compliance with Safe Handling and Release Equipment On Board. NOAA Fisheries must
ensure NOAA Fisheries’ Office of Law Enforcement (OLE), in cooperation with the U.S.
Coast Guard and state law enforcement partners, receive training on the new safe handling and
release equipment requirements and conduct dock-side and at-sea boardings that ensure that the
gear is on board.
f) Compliance with vessel safety requirements for observer coverage. NOAA Fisheries must
establish procedures to notify OLE of any vessel authorized to fish with pelagic longline gear
and selected for observer coverage that is found to be inadequate or unsafe for purposes of
carrying an observer and for allowing operation of normal observer function. Such vessels are
prohibited from fishing without observer coverage. NOAA Fisheries must establish procedures
for those vessels issue regulations requiring vessels authorized to fish with HMS pelagic
longline gear to notify the OLE and POP when safety problems have been corrected, before the
vessel conducts another fishing trip.

9-4

10.0

Conservation Recommendations

Section 7(a)(1) of the ESA directs federal agencies to utilize their authorities to further the
purposes of the ESA by carrying out conservation programs for the benefit of endangered and
threatened species. Conservation recommendations are discretionary agency activities to minimize
or avoid adverse effects of a proposed action on listed species or critical habitat, to help implement
recovery plans, or to develop information.
(a) In-water Abundance Studies. In order to better understand sea turtle populations and the
impacts of incidental take in HMS fisheries, NOAA Fisheries should support in-water
abundance estimates of sea turtles to achieve more accurate status assessments for these species
and improve our ability to monitor them.
(b) Population Modeling. Once reasonable in-water estimates are obtained, NOAA Fisheries
should support population modeling or other risk analyses of the sea turtle populations affected
by HMS, as well as other, fisheries. This will help improve the accuracy of future assessments
of the effects of different levels of take on sea turtle populations.
(c) International Fisherman Education. NOAA Fisheries should ensure that the Sea Turtle
Handling Guidelines and Careful Release Protocols for Release with Minimum Injury are
translated into various languages (e.g., Portuguese, Spanish, Italian, Greek, Vietnamese,
Japanese, Chinese), printed, and distributed appropriately throughout the longline fisheries
operating in the North Atlantic and Mediterranean in order to enhance survival of all
turtles/subpopulations hooked, even those taken by foreign countries (as these fisheries all
impact shared sea turtle populations).
(d) International Negotiations. NOAA Fisheries should focus efforts on the broader impacts from
longline fishing on loggerhead and leatherback populations throughout the Atlantic by using
its available legal authorities (e.g., Sec. 202(h) of the MSFCMA and Sec. 609(a) of Public Law
101-162) to pursue bilateral or multilateral agreements for the protection and conservation of
sea turtles with other nations whose commercial longline fleets may affect sea turtles. NOAA
Fisheries, in partnership with the U.S. Department of State, should make every effort to use
existing bilateral and multilateral mechanisms to which the U.S. is a party to focus the actions
of those mechanisms on the problem of sea turtle-longline bycatch and to promote the use of
the mitigation measures described in the proposed action. Such existing multi-lateral
mechanisms may include ICCAT, the U.N. Food and Agriculture Organization Committee on
Fisheries (FAO/COFI), the Inter-American Convention for the Protection and Conservation of
Sea Turtles, the Asia Pacific Fisheries Commission, and the Convention on the Conservation
and Management of Highly Migratory Fish Stocks in the Western and Central Pacific. Another
potential additional mechanism includes the Indian Ocean Regional MOU for the Conservation
and Management of Sea Turtles. Efforts should focus on strenghthening information collection
on rates of sea turtle interactions, promoting bycatch reduction measures that have proven
effective, stimulating international research on reducing sea turtle-longline interactions, and
10-1

promoting the development of binding international mechanisms to address sea turtle-longline
interactions. If successful adoption of bycatch reduction measures by foreign fleets does not
occur, NOAA Fisheries should seek additional legislative authority to address the threat of
international longline fisheries to sea turtles, similar to section 609(b) of Public Law
101-162.In addition, NOAA Fisheries should pursue similar avenues to promote international
sea turtle conservation in general, but with particular emphasis on protecting leatherback sea
turtles in the Guianas on their nesting beaches and from incidental capture in coastal gillnet and
trawl fisheries.
(e) Enhance understanding of leatherback nesting status. NOAA Fisheries should examine ways
to obtain more accurate, consistent surveys of leatherback nesting beaches in the Guianas,
Suriname, and Trinidad. These beaches are by far the largest and most important nesting
beaches for leatherbacks in the western Atlantic. A better understanding of the dynamics of
these beaches, as well as more consistent data, are necessary to be able to utilize the
information to make valid assessments about the population status and trends, and therefore to
make better management decisions.
(f) Effectiveness of MARPOL. NOAA Fisheries should meet with representatives of the U.S.
Coast Guard to determine what benefits, if quantifiable, have accrued since the signing of the
MARPOL agreement limiting pollution and dumping at sea; and explore ways with the Coast
Guard to make this agreement more effective and to improve compliance through enforcement
and outreach.
(g) Improved method of evaluating take levels. The SEFSC should devise a probability-based
approach or other statistical method to evaluate take in the HMS pelagic longline fishery. Use
of such a method, instead of using a single number to indicate exceedance of the ITS, may
provide a better approach to evaluating the actual risk of greater than expected take levels
occurring. Such an approach would allow NOAA Fisheries to establish a trigger that reduces
the likelihood of requiring reinitiation unnecessarily because of inherent variability in take
levels (which is expected to be large), but still allows for an accurate assessment of how the
fishery is performing versus expectations. Once such a method is devised, SEFSC and SEROPRD would then consult to determine whether the new approach is biologically valid and
equivalent to the current method, and provides a better tool for evaluating and managing takes
in the HMS pelagic longline fishery.

10-2

11.0

Reinitiation of Consultation

This concludes formal consultation on the continued operation of the HMS pelagic longline
fishery, as regulated by the HMS FMP, as amended. As provided in 50 CFR §402.16, reinitiation
of formal consultation is required where discretionary federal agency involvement or control over
the action has been retained (or is authorized by law) and if: (1) the amount or extent of taking
specified in the incidental take statement is exceeded, (2) new information reveals effects of the
action that may affect listed species or critical habitat in a manner or to an extent not previously
considered, (3) the identified action is subsequently modified in a manner that causes an effect to
listed species or critical habitat that was not considered in the Opinion (i.e., proposed quota
reduction and limited access rules are changed), or (4) a new species is listed or critical habitat
designated that may be affected by the identified action. If the amount or extent of incidental take
is exceeded, the HMS Division must immediately request reinitiation of formal consultation.

11-1

12.0

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Jekyll Island, Georgia.
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mammals taken incidental to commercial fishing operations: Report of the serious injury
workshop 1-2 April 1997, Silver Spring, Maryland. NOAA Technical Memorandum
NOAA Fisheries-OPR-13. January, 1998.
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Balazs, G.H. 1983. Recovery records of adult green turtles observed or originally tagged at
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Shomura, R.S. and H.O. Yoshida (eds.), Proceedings of the workshop on the fate and
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Hawaiian green turtle stock. Submitted to Biological Conservation. August, 2003.

12-1

Balazs, G.H., S.G. Pooley, and S.K.K. Murkawa. 1995. Guidelines for handling marine turtles
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Honolulu, Hawaii, March 15-17, 1995. NOAA Technical Memorandum NOAA-NMFSSWFSC-222.
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