0380 ss rev part b 042208

SUPPORTING STATEMENT
LARGE PELAGIC FISHING SURVEY
OMB CONTROL NO.: 0648-0380

B. COLLECTIONS OF INFORMATION EMPLOYING STATISTICAL METHODS
1. Describe (including a numerical estimate) the potential respondent universe and any
sampling or other respondent selection method to be used. Data on the number of entities
(e.g. establishments, State and local governmental units, households, or persons) in the
universe and the corresponding sample are to be provided in tabular form. The
tabulation must also include expected response rates for the collection as a whole. If the
collection has been conducted before, provide the actual response rate achieved.
The LPS utilizes a "complemented surveys" approach, which includes both a telephone survey of
permit holders (about 22,500 potential respondents) to estimate fishing effort and an intercept
survey of anglers and captains at fishing sites to obtain catch data and biological data. This
approach was developed and tested over a period of several years to minimize response and
sampling errors for the different data elements. NMFS is a leader in the field of survey sampling
of marine recreational fishermen.
Refusal rates of eligible LPS respondents intercepted for dockside interviews and biological
sampling are consistently less than 5%. Large pelagic telephone survey refusal rates (of those
eligible respondents actually contacted) vary by state but are typically between 5% and 10%. In
general, higher response rates are expected on the Large Pelagic Survey since participation is
mandatory and is a condition of receiving an HMS permit to fish for large pelagic species.
2. Describe the procedures for the collection, including: the statistical methodology for
stratification and sample selection; the estimation procedure; the degree of accuracy
needed for the purpose described in the justification; any unusual problems requiring
specialized sampling procedures; and any use of periodic (less frequent than annual) data
collection cycles to reduce burden.
The LPS is used by NMFS to monitor recreational fisheries for large pelagics including tunas,
billfish, sharks, dolphinfish, amberjack and wahoo. The LPS is used to collect the data needed
for generating estimates of both the recreational fishing effort directed at large pelagic fishes and
the recreational landings of these species.
Accurate landings estimates are needed for effective quota monitoring of the recreational fishery
for bluefin tuna because the International Commission for the Conservation of Atlantic Tunas
(ICCAT) has recommended that countries limit harvest of school size West Atlantic bluefin tuna
(BFT) to 8% of the national quota. The LPS is also used to collect landings data for seasonal
catch estimates for billfishes, sharks, and tunas other than BFT (e.g., yellowfin, albacore), and to
collect biological data on BFT and other large pelagic species.
The LPS estimates recreational BFT landings by multiplying the estimated average number of
BFT landed per trip by the total number of vessel trips. Due to the migratory nature of large
pelagic fishes, the LPS design considers geographic and seasonal variation in fish distribution
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and the differences in effort catch characteristics of the fishing fleet. Given this variation and the
data requirements for estimating the components of the generalized catch equation, the survey
incorporates a multi-frame, stratified random sampling design. Specifically, the LPS consists of
two complementary components: a directory frame telephone survey of tuna and/or HMS permit
holders to obtain fishing trip information, and a dockside survey that collects landings
information from anglers as they complete each trip and that also estimates the proportion of
vessels fishing for large pelagics that are not in the telephone frame (non-permitted vessels and
vessels fishing out of state).
The telephone sample frame is determined by sorting vessels by state and boat type using tuna
and/or HMS permit listings. The stratification scheme includes seven geographic strata,
corresponding to a state or groups of states, weekly (or bi-weekly) temporal strata, and two
fishing vessel strata, private boats and charter boats. This level of stratification is necessary due
to the pulsed nature of the fishery as pelagic fish undertake summer feeding migrations through
the mid-Atlantic and southern New England areas. Thus, estimates of sample frame size, average
catch, and average fishing effort are needed for each combination of geographic, temporal and
vessel type strata and the estimated total annual catch is the sum of the estimates produced for
each stratum.
Landings data are collected by interviewing boat captains or boat owners at the completion of a
fishing trip for large pelagics and recording data on permit status of the vessel and the size,
number, and species composition of the catch by all anglers on the vessel from that trip.
Dockside interviews are conducted throughout the fishing season on a weekly basis, generally
from June through October. The intercept sample frame consists of a random cluster of
individual vessel trips at selected fishing sites. Selection of sampling sites or sites clusters (i.e.,
nearby sites grouped together for sampling) is based on the expected number of large pelagic
fishing trips at each site/cluster, a determination based not only on the number of vessels docked
at a port but also on the expected fishing pressure given the current distribution of large pelagic
fish. Thus, heavily used sites/clusters are more likely to be selected for sampling.
Fishing effort data are collected through a weekly (charter boats) or bi-weekly (private boats)
telephone survey of boat captains and vessel owners about trips taken during the previous one or
two week period. The telephone survey sample frame consists of a list of boat owners and
captains compiled from tuna and/or HMS permit files. Data collected on the telephone survey
include participation status and, if verified as a participant in the fishery, the number of large
pelagic fishing trips taken during the week (or two weeks) prior to the call, on a per boat basis.
To calculate total trips, the number of vessels on the frame multiplies the average number of trips
by respondents. An adjustment is necessary because a vessel may not be present on the permit
frame, or may be intercepted in a state other than the vessel’s identified homeport. This
adjustment provides a better estimate the total number of vessel trips by both in and out of frame
vessels, and allows the matching of information from the dockside survey with that from the
telephone survey.
The total landings are estimated by multiplying the adjusted total trips for each state and boat
type by the average landings recorded for that state and boat type. Variances, standard errors
and coefficients of variation are estimated for each estimate of effort and catch. Control of
response biases such as time-related recall error, telescoping, fish misidentification and
prestige bias have resulted in the choice of the unique complemented surveys approach.
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3. Describe the methods used to maximize response rates and to deal with nonresponse.
The accuracy and reliability of the information collected must be shown to be adequate for
the intended uses. For collections based on sampling, a special justification must be
provided if they will not yield "reliable" data that can be generalized to the universe
studied.
As discussed in Item #1 above, due to the mandatory nature of the survey response rates for
Large Pelagics Surveys are typically high. Field interviewers are instructed on how to be nonintrusive in soliciting cooperation. Providing telephone survey respondents with the option of
faxing in their data or calling back a toll-free number at their convenience were put in place to
maximize response rates.
Intensive interviewer training and tested methodological approaches are employed to maximize
response rates. Interviewers are tested for skills in fish identification, effective communication
with potential respondents, and/or accurate coding of responses before they are hired for
training. Training familiarizes interviewers with procedures and develops their interviewing
skills through role playing exercises. Supervision and additional training of interviewers occurs
during the conduct of both the telephone and intercept surveys. Field supervisors visit intercept
survey interviewers periodically to observe their performance and provide additional training as
needed. Contractor staff and NMFS staff to ensure consistency in survey administration
monitor telephone interviewers. Other data quality assurance and quality control measures
include phone validation of dockside interviews, surprise field visits by interviewer
supervisors, data review meetings (local and coast-wide), and automated error-checking
programs. Procedures for maintaining the integrity of the various sampling designs are clearly
outlined in the statement of work and closely tracked by NMFS to ensure proper execution.
4. Describe any tests of procedures or methods to be undertaken. Tests are encouraged as
effective means to refine collections, but if ten or more test respondents are involved,
OMB must give prior approval.
More than 10 years of testing, methodological research and professional experience in survey
work were used in formulating the present methodology.
5. Provide the name and telephone number of individuals consulted on the statistical
aspects of the design, and the name of the agency unit, contractor(s), grantee(s), or
other person(s) who will actually collect and/or analyze the information for the agency.
Ronald Salz (301-713-2328) is the NMFS contact for the Large Pelagics Survey. The present
contractor for the dockside intercept survey is QuanTech, Inc. of Rosslyn, Virginia. The present
contractor for the telephone interview survey is also QuanTech. Data collections are performed
under contract; NMFS staff performs analyses.

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