Economic Estimates of Invasive Wild Pig Damages to Crops 2019

University of Nebraska - Lincoln

DigitalCommons@University of Nebraska - Lincoln
USDA National Wildlife Research Center - Staff
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U.S. Department of Agriculture: Animal and
Plant Health Inspection Service

2-16-2020

Economic estimates of invasive wild pig damage to crops in 12
US states
Sophie McKee
USDA/APHIS/WS National Wildlife Research Center & Colorado State University,
[email protected]

Aaron Anderson
USDA/APHIS/WS National Wildlife Research Center

Keith Carlisle
USDA/APHIS/WS National Wildlife Research Center & Colorado State University

Stephanie A. Shwiff
USDA/APHIS/WS National Wildlife Research Center

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McKee, Sophie; Anderson, Aaron; Carlisle, Keith; and Shwiff, Stephanie A., "Economic estimates of
invasive wild pig damage to crops in 12 US states" (2020). USDA National Wildlife Research Center - Staff
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Crop Protection 132 (2020) 105105

Contents lists available at ScienceDirect

Crop Protection
journal homepage: www.elsevier.com/locate/cropro

Economic estimates of invasive wild pig damage to crops in 12 US states
Sophie McKee a, b, *, Aaron Anderson a, Keith Carlisle a, b, Stephanie A. Shwiff a
a
b

USDA/APHIS/WS National Wildlife Research Center, 4101 Laporte Avenue Fort Collins, Colorado, 80521, USA
Colorado State University, USA

A R T I C L E I N F O

A B S T R A C T

Keywords:
Feral swine
Invasive species
Crop damage
Survey
Control methods

We report the results of a survey on invasive wild pig (Sus scrofa L.) damage and control in 12 US states (Ala­
bama, Arkansas, California, Florida, Georgia, Louisiana, Mississippi, Missouri, North Carolina, Oklahoma, South
Carolina, and Texas). The crops chosen for this study represent the “second tier” in terms of economic importance
after the six crops that were the subject of Anderson et al. (2016). The survey was distributed by the USDA
National Agricultural Statistical Service (NASS) in the summer of 2019 to a sample of producers in each of the
states (except California) of the following six crops: hay, pecans (Carya illinoinensis (Wangenh.) K.Koch), melons
(cantaloupe (Cucumis melo L. var. cantalupensis), honeydew (Cucumis melo L. (Inodorus Group)), and watermelon
(Citrullus Schrad.), sugarcane (Saccharum officinarum L.), sweet potatoes (Ipomoea batatas (L.) Lam.), and cotton
(Gossypium L.). In California, where there the crops of economic importance differed from the other states in the
study, damages were calculated for producers of hay, almonds (Prunus dulcis (Mill.) D.A. Webb), grapes (Vitis
vinifera L.), sod, carrots (Daucus L.), lettuce (Lactuca L.), and strawberries (Fragaria L.). In total, 7438 respondents
completed the questionnaire. Findings indicate that damage can be substantial. The highest yield loss estimates
occurred for hay in Texas. Control efforts were common, but no control method was rated by the majority of
producers as very effective. Extrapolating crop damage estimates to the state-level in 12 states with reportable
damage yielded an estimated crop loss of $272 million/yr. Though large, this number likely represents only a
small fraction of the total damage by wild pigs in these states because it only includes crop damage to six crops.
We hope findings from this survey will help guide control efforts and research, as well as serve as a benchmark
against which the effectiveness of future control efforts can be measured.

1. Introduction
Wild pigs (Sus scrofa L.), also known as wild boar, wild/feral swine,
wild/feral hogs, and feral pigs (Keiter et al., 2016), are a non-native,
invasive species in the U.S. that is responsible for a wide range of
negative impacts, including damage to crops and livestock (Harper
et al., 2016). The most widely cited aggregate estimate of wild pig
damages in the U.S. comes from a 2007 study that conservatively esti­
mates annual crop damages and control costs at $1.5 billion (Pimentel,
2007). The author based the estimate on a population of 5 million wild
pigs in the U.S. and $3001 in crop damages and control costs per swine
(Pimentel, 2007). In the decade after the study was published, the
geographic area of wild pig distribution increased by more than 25

percent (Corn and Jordan, 2017) despite substantial investments in
control (Pepin et al., 2019), and evidence suggests that the species’
population density continued to grow in many areas where populations
have long been established (see Fig. 1 from Lewis et al. (2019) below).
Crops are seen as a contributing factor to the expansion of the wild
pig population (Brook and van Beest, 2014; McClure et al., 2015; Lewis
et al., 2017; Snow et al., 2017). Total annual damages and control costs
in the U.S. may therefore be much higher than $1.5 billion, and the
development of a more accurate estimate of total costs and damage has
taken on increased urgency with the growth and spread of wild pig
populations. To that end, recent efforts have been made to produce more
rigorous estimates of wild pig impacts at aggregated levels. In a survey
study focused on six high value crops (corn (Zea mays L.), soybeans

* Corresponding author. USDA/APHIS/WS National Wildlife Research Center, 4101 Laporte Avenue Fort Collins, Colorado, 80521, USA.
E-mail address: [email protected] (S. McKee).
1
Pimentel (2007) provides little information to explain how he arrived at $300 per pig. As a result, it is not possible to build off of, or refine, the figure as our
understanding of the scope and magnitude of wild pig-related costs and damages increases.

https://doi.org/10.1016/j.cropro.2020.105105
Received 6 December 2019; Received in revised form 31 January 2020; Accepted 4 February 2020
Available online 16 February 2020
0261-2194/© 2020 Elsevier Ltd. All rights reserved.
U.S. government works are not subject to copyright.

S. McKee et al.

Crop Protection 132 (2020) 105105

Fig. 1. Predicted potential population density of wild pigs across the United States for 1982 (a), 1988 (b), 2004 (c), 2010 (d), 2013 (e), and 2016 (f). from Lewis
et al. (2019) Predicted population density ranges across values of low (yellow: 0–2 animals/km2), medium (orange: 3–5 animals/km2), and high (red:
6–8 animals/km2).

2

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Crop Protection 132 (2020) 105105

Our focus here is on four types of information collected by the sur­
vey. The first is the presence of wild pigs. Wild pig presence provides a
general indication of the economic threat they pose in the area, either
through direct damage or the risk of disease transmission. We asked two
general questions regarding wild pig presence in the producer’s county
and on their operation (Fig. 2).
General information on damage to crops and property was then
solicited by questions listed in Figs. 3 and 4. Wild pigs damage pasture
and agricultural crops by consumption, rooting, digging, and trampling
(Seward et al., 2004). Producers could choose to respond for up to three
of their highest valued crops harvested on their operation in 2018. Each
producer was asked if there were any crops, including trees/orchards,
hay, and sod, harvested on their operation in 2018. If so, they could
report up to three crops. For each of these crops, they were asked if, to
the best of their knowledge, wild pigs had been present on any field of
the crop, if the presence of wild pigs made the crop more costly to
harvest, and if there was crop damage from wild pigs on acres harvested
in 2018. Sections on livestock production and damage, property dam­
age, wild pig control methods, and hunting followed.
The structure of the questions related to crop damage enabled us to
capture information from producers that experienced no crop damage
from wild pigs so that we could use the survey results to extrapolate to
the state-level. The questions also go beyond simply soliciting a per­
centage yield loss response. Instead, producers were asked how many of
the acres of each crop were damaged by wild pigs, as well as actual yield
with the damage and expected yield without the damage on those acres.
Self-reporting wildlife damages the crops is common and has been
shown to be accurate (Conover, 2002; Johnson-Nistler et al., 2005;
Tzilkowski et al., 2002; Wywialowski, 1994).
To calculate wild pig damage to crops, we compared actual yield
reported by each producer to the expected yield reported if no wild pig
damage had occurred. Specifically, each producer reported total acres
harvested for each of up to three crops, as well as average yield per acre,
giving total yield. For crop j on producer i’s operation, this is:
�
�
Yield ij ¼ acres harvestedij avg: yield per acreij :
(1)

(Glycine max (L.) Merr), wheat (Triticum L.), rice (Oryza L.), peanuts
(Arachis L.), and sorghum (Sorghum Moench)) in 11 states (Alabama,
Arkansas, California,2 Florida, Georgia, Louisiana, Mississippi, Missouri,
North Carolina, South Carolina, and Texas), Anderson et al. (2016)
found an estimated $190 million in crop production was lost in 2014. In
a subsequent survey study focused on the same 11 states plus Oklahoma
and Tennessee, Anderson et al. (2019) found that estimated damages
from wild pigs to livestock on account of predation and disease were $40
million in 2016.
For the present study, a survey was administered by the USDA Na­
tional Agricultural Statistics Service (NASS) in 2019 to producers of
targeted crops in 12 states to determine costs and damages associated
with wild pigs. The 12 states are the same states that were the focus of
Anderson et al. (2016), with the addition of Oklahoma. The crops chosen
for this study represent the “second tier” in terms of economic impor­
tance after the six crops that were the subject of Anderson et al. (2016).
The crops and states were selected through a subjective evaluation of
economic importance, vulnerability of wild pigs, and political consid­
erations. In each of the states except for California, damage costs were
calculated for producers of the following six crop categories: hay, pecans
(Carya illinoinensis (Wangenh.) K.Koch), melons (cantaloupe (Cucumis
melo L. var. cantalupensis), honeydew (Cucumis melo L. (Inodorus
Group)), and watermelon (Citrullus Schrad.), sugarcane (Saccharum
officinarum L.), sweet potatoes (Ipomoea batatas (L.) Lam.), and cotton
(Gossypium L.). In California, where there the crops of economic
importance differed from the other states in the study, damages were
calculated for producers of hay, almonds (Prunus dulcis (Mill.) D.A.
Webb), grapes (Vitis vinifera L.), sod, carrots (Daucus L.), lettuce (Lactuca
L.), and strawberries (Fragaria L.).
The survey was designed to simultaneously capture information
related to wild pig presence, crop damage, livestock losses, control
methods, live sales, and hunting, but the focus of the present analysis is
on wild pig presence, crop damage, and control efforts. We proceed with
a discussion of the survey distribution, NASS rules related to disclosure
of information, and the survey instrument. Results are then presented,
followed by a discussion of the implications of the findings.

If some acres were reported damaged by wild pigs, producers re­
ported: (i) the number of acres damaged, (ii) average yield per acre on
damaged acres, and (iii) expected yield per acre if these acres had not
been damaged. Hypothetical yield losses for each producer’s crops are
then calculated as:
�
�
�
Lossij ¼ acres damagedij avg: yield not damagedij avg: yield w damageij :

2. Methods
A self-administered survey questionnaire was mailed in July 2019 to
15,067 producers in the 12 states, along with a stamped return envelope.
Additionally, representatives of NASS made up to ten follow-up calls to
non-respondents in an effort to administer the survey by phone. In total,
7,438 respondents completed the questionnaire, for a response rate of
49.3%.
To calculate estimates of wild pig impacts at the state level, weights
provided by NASS were used to account for state-wide production of
each crop. Additionally, individual-level responses were weighted to
account for non-response by other producers in the sample, rendering
estimates of wild pig damages representative at the state level. In cases
where either a single producer made up a large portion of responses to a
specific question or only a few individuals responded to the questions,
NASS rules prevent disclosure of values to in order to protect the private
information of producers. At the state level, these disclosure re­
quirements are largely unrestrictive in terms of limiting presentable
results. Some survey responses at the more disaggregated level of crops
within states were not as immune to disclosure concerns and were
consequently suppressed. For this reason, summary statistics at the
state-crop level cannot be reported in some cases, because of the low
response rate results in some categories being dominated by a single
producer.

(2)
Since actual yield on damaged acres was included in the original
calculation of total yield in (1), hypothetical yield without wild pig
damage is the sum of (1) and (2). Hypothetical yield loss due to wild pig
damage as a percentage of total (hypothetical) yield is then:
Percent Lossij ¼ 100 �

Lossij
:
Yieldij þ Lossij

(3)

Equation (3) gives the portion of yield lost to wild pig damage at the
producer-crop level. To calculate the portion of yield lost for each crop
within each state, we summed yield and hypothetical loss across all
producers of each crop in each state as in (1) and (2), and used these to
calculate the portion of each crop’s yield lost to wild pigs across the
state. Along with the producer level responses needed to calculate (3),
each producer was given a calculated weight based on a non-response
adjustment and Multivariate Probability Proportional to Size (MPPS)
weight, as in Kott et al. (1998). These producer-level weights were

2
Estimated damages for California were not included in the publication and
were not taken into account in calculating total estimated damages due to
privacy concerns.

3

S. McKee et al.

Crop Protection 132 (2020) 105105

Fig. 2. Wild pig presence questions from the survey instrument.

adjusted to account for non-response to specific questions and used in
the calculations that follow, specifically by weighting each producer’s
yields and losses in (1) and (2) by their unique weight in order to obtain
a representative value at the state level.
To estimate the dollar value of production lost to wild pig damage for
the selected crops at the state level, we assumed that the weights used to
account for non-response and farm size are also applicable to wild pig
damage. In other words, we assumed that the damage experienced by
the weighted sample of observed producers is representative of all
producers of the same crop in their state. Under this assumption, esti­
mated production value lost to wild pigs is the percentage loss by state
and crop from Table 1. For crop j in state s, the calculation of percentage
loss analogous to (3) is:

3. Results

reported that wild pigs make it more costly for them to harvest their
crop, and 33% reported property damage from wild pigs. Among indi­
vidual states, respondents from Texas and Oklahoma were most likely to
indicate the presence of wild pigs on their land (70%, and 58%
respectively), that wild pigs make it more costly for them to harvest their
crop (55% and 44%), damage by wild pigs to crops (59% and 49%), and
damage by wild pigs to property (73% and 65%). Complete results are
presented in Table A-2 in the Appendix.
We note that some observations of crop-level data were unusable (e.
g. a producer reported wild pig damage to a crop but no acres were
damaged, or a producer reported on crops other than those listed in
Table 1). Table A-3 in the Appendix reports the number of useable ob­
servations for calculating percentage yield loss at the state-crop level.
Hay, tree nuts, and cotton provide the largest sample sizes.
The results of the yield loss calculations for the crops of interest are
presented in Table 1. Mean reported damage to hay was markedly
higher in Texas (6.59%), Georgia (6.51%), and Louisiana (6.03%), while
reported pecan damage was substantially higher in Texas (13.46%) and
Florida (12.56%).
Estimates of production value lost to wild pigs, as calculated in (5),
are presented in Table 2. For the selected crops and states which are
reportable, an estimated $272 million in crop production was lost to
wild pig damage in 2018. A comparison across crops shows that hay has
the highest value of reported crop losses ($162,626). However, given the
total value of production in the 12 states of the different crops, tree nut
production suffers much larger monetary losses as a percentage of total
production value (13.46% in Texas, 12.56% in Florida). The results also
indicate that Texas suffers substantially larger monetary losses than
other states ($115,978).

3.1. Wild pig presence in county and on operation

3.3. Wild pig control

Figs. 6 and 7 present the percentage of respondents by state who
reported wild pig presence in their county and on their operation during
the previous three years. Complete results are shown in Table A.1. in the
Appendix. 59% of the producers of the targeted commodities in these
states reported being aware of wild pig presence in their county, and
38% of the producers reported being aware of wild pig presence on their
operation during this period. The highest proportion of producers
reporting wild pig presence on their property is in Texas at 78%, fol­
lowed by Oklahoma at 67%.

Fig. 9 depicts for each state the percentage of producers who re­
ported making attempts to control wild pigs, both in general and by
specific control method. Full results are presented in Table A-4 in the
appendix. More than one third (34%) mentioned at least one control
method being used on their property in 2018. Across all twelve states,
the most widely used control method was shooting wild pigs on sight
(26%), followed by hunting without dogs and trapping and removing
(both at 16%). The least widely used (1%) was repellents. The state with
the highest rate of control was Texas at 75%. Producers were also asked
if they would be likely to use a reasonably-priced wild pig toxicant on
their operation if it were available and if it caused minimal suffering,
posed no risk to human health, and caused little harm to other wildlife.
The proportion of producers who answered in the affirmative is pre­
sented in the last column of Table A-4. 55% replied positively across the
12 states. The highest proportion of positive responses can be found in
Texas at 68% and the lowest in California at 35%.
Producers were also asked to rate the effectiveness of a control
method if they used it. Results are presented in Table 3. Hunting with
dogs is the method most often rated as very effective.

Percent Lossjs ¼ 100 �

Lossjs
:
Yield js þ Lossjs

The dollar value of lost production in dollars is then
�
�
Percent Lossjs Productionjs
Lossjs ¼
:
100 Percent Lossjs

(4)

(5)

Current production value for the selected crops and states
Productionjs were obtained from NASS Quick Stats for the year20173 (the
most recent available census year at the time of writing).
Additional questions solicited information on wild pig control efforts
(Fig. 5). Producers were asked about the use of each method, the cost of
each method, and their perceptions about the effectiveness of each
method.

3.2. Wild pig damage
Fig. 8 shows responses by state to the following questions: (i) pres­
ence of wild pigs on a respondent’s crops, (ii) additional cost to harvest
crops on account of wild pigs, (iii) damage from wild pigs on crops
harvested, and (iv) damage to any of the property items listed in Fig. 4
from wild pigs in 2018. Across all 12 states, one-third of producers re­
ported wild pig presence on their land, 29% reported crop damage, 23%
3

Or the closest year when 2017 data wasn’t available.
4

S. McKee et al.

Crop Protection 132 (2020) 105105

Fig. 3. Wild pig crop damage questions from the survey instrument.

5

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Crop Protection 132 (2020) 105105

Fig. 4. Wild pig control questions from the survey instrument.

6

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Crop Protection 132 (2020) 105105

Table 1
Percent of crop lost to wild pigs (aggregated by states).
State

Hay, haylage

Pecans almonds

Melons

Sugarcane

Sweet potatoes

Cotton

Grapes

Lettuce

Strawberry

Alabama
Arkansas
California
Florida
Georgia
Louisiana
Mississippi
Missouri
North Carolina
Oklahoma
South Carolina
Texas

4.46%
4.90%
0.45%
2.06%
6.51%
6.03%
0.91%
2.47%
0.15%
3.08%
1.35%
6.59%

6.95%
0.93%
0.04%
12.56%
5.67%
2.90%
0.00%
NA
0.00%
3.93%
0.00%
13.46%

0.00%
(D)
NA
1.84%
0.48%
(D)
(D)
0.00%
0.00%
(D)
1.03%
8.36%

NA
NA
NA
0.90%
NA
0.35%
NA
NA
NA
NA
(D)
0.00%

5.17%
(D)
NA
(D)
1.64%
(D)
1.04%
(D)
1.74%
(D)
0.00%
(D)

0.89%
0.26%
NA
3.01%
2.01%
0.00%
0.05%
0.00%
0.11%
0.35%
1.88%
0.37%

NA
NA
0.22%
NA
NA
NA
NA
NA
NA
NA
NA
NA

NA
NA
0.00%
NA
NA
NA
NA
NA
NA
NA
NA
NA

NA
NA
0.06%
NA
NA
NA
NA
NA
NA
NA
NA
NA

Fig. 5. Wild pig control questions from the survey instrument.

7

S. McKee et al.

Crop Protection 132 (2020) 105105

Fig. 6. Percent of landowners reporting wild pig presence in county.

Fig. 7. Percent of landowners reporting wild pig presence on operation.

8

S. McKee et al.

Crop Protection 132 (2020) 105105

Fig. 8. Percent from each state reporting presence on land and damage.
Table 2
Lost value from feral pigs (1000 US $).
State

Hay

Tree Nuts

Melons

Sugarcane

Sweet Potatoes

Cotton

Grapes

Lettuce

Strawberry

Total

Alabama
Arkansas
California
Florida
Georgia
Louisiana
Mississippi
Missouri
North Carolina
Oklahoma
South Carolina
Texas

9834
13,272
5918
2472
12,263
6335
1212
14,922
272
15,749
1501
78,875

271
33
2065
271
17,873
366
–
NA
–
990
–
17,112

NA
(D)
NA
3062
480
(D)
(D)
–
–
(D)
333
8838

NA
NA
NA
5809
NA
1232
NA
NA
NA
NA
NA
–

642
(D)
NA
(D)
9
(D)
961
(D)
5349
(D)
–
(D)

2746
1110
NA
1820
17,980
–
261
–
319
1330
3494
11,153

NA
NA
1909
NA
NA
NA
NA
NA
NA
NA
NA
NA

NA
NA
–
NA
NA
NA
NA
NA
NA
NA
NA
NA

NA
NA
1501
NA
NA
NA
NA
NA
NA
NA
NA
NA

13,493
14,415
11,393
13,434
48,604
7932
2434
14,922
5939
18,069
5328
115,978

Total

162,626

38,979

12,714

7041

6960

40,212

1909

–

1501

271,942

Fig. 9. Percent from each state reporting control and willingness to use poison.

9

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Crop Protection 132 (2020) 105105

value crops that are attractive to wild pigs to less profitable but less
palatable crops has also probably occurred as their range and density has
increased. Moreover, 23% of respondents reported that wild pigs make it
more costly for them to harvest their crops. These additional costs or lost
revenues are not quantified in this study and are left to further research.
The economic burden of crop damage to crop producers from wild
pigs is not limited to the lost production or increase in harvest costs; it
also includes the substantial additional cost of control efforts. Many
growers reported applying a suite of control methods (34%), the most
common being shooting pigs on sight (26%), but no method was rated as
extremely effective by the majority of the respondents. These results
suggest that more research on effective control methods or combinations
of control methods would be beneficial. The majority of growers (55%)
appear willing to use a wild pig toxicant on their operation if certain
safety criteria were met.
Several limitations of the survey and its analysis should be
acknowledged. First, producers may not have accurate perceptions of
damage. Such biases may be intentional or unintentional. Also, we are
unable to fully characterize all non-response bias that may be present.
NASS expended considerable effort to minimize the number of nonresponses, and the response rate was high at about 49%. However, the
possibility of bias remains because respondents may have been more
likely to incur damage than non-respondents. Furthermore, we use
NASS’s state-level production value estimates to address potential crop
value variability across states, which could occur notably for hay, but we
acknowledge that there may also be variation in crop composition
within states that is not accounted for. Additionally, missing, incom­
plete, or meaningless responses at the individual level, which we
accounted for by scaling up response weights, are another potential
source of bias. Finally, sample sizes for some questions and state-crop
combinations are quite small, and in some cases NASS rules prevent
disclosure of any information garnered from specific questions.

Table 3
Perceived effectiveness by control method.

Shooting wild pigs
on sight
Hunting wild pigs
with dogs
Hunting wild pigs
without dogs
Aerial Hunting
Trapping and
removing
Repellents

Not
effective

Slightly
effective

Moderately
effective

Very
effective

0.14
(0.02)
0.17
(0.05)
0.29
(0.08)
0.55
(0.19)
0.11
(0.04)
0.66
(0.15)

0.49
(0.06)
0.27
(0.07)
0.35
(0.06)
0.06
(0.03)
0.45
(0.10)
0.26
(0.12)

0.24
(0.05)
0.23
(0.06)
0.23
(0.06)
0.21
(0.11)
0.31
(0.11)
0.05
(0.03)

0.13
(0.03)
0.33
(0.13)
0.13
(0.04)
0.18
(0.10)
0.13
(0.04)
0.04
(0.03)

4. Conclusion
Agricultural crops are a resource providing abundant calories, pro­
tein, and essential fatty acids for wildlife, making them particularly
vulnerable to damage and consumption (Birnie-Gauvin et al., 2017). Our
findings suggest that of 12 the states and the subset of crops included in
this study, wild pigs impose the largest burden on agricultural producers
in Texas, which can be explained both by the widespread distribution of
wild pigs and the importance of crop production in the state. Among the
crops surveyed, the highest loss ratio was reported for pecans (Texas
13.46% and Florida 12.56%). During rooting, wild pigs turn up the soil
with their noses in search of food, making large depressions in the
ground, which interfere with pecan harvest machinery, making harvest
less efficient, resulting in loss of yields. Additionally, direct consumption
of agricultural crops further reduces yields and profits to agricultural
producers (Boyer et al., 2019). Overall, the loss ratio for cotton was
lower, ranging from 0% in Missouri to 3.1% in Florida. These results are
in line with observations from a crop use study in described in Wilber
et al. (2019): fruit and nut crops had the greatest crop use per hour of
collaring time, followed by cereal, cotton, sugar, oilseed, and grasses.
Our results suggest that wild pig damage to crops is common across
crop types and widespread geographically. A total production loss of
nearly $272 million represents a substantial loss for crop producers,
many of which typically operate on very small profit margins. Although
such effects are unaccounted for here, a shift in production from high

CRediT authorship contribution statement
Sophie McKee: Formal analysis, Writing - original draft, Writing review & editing. Aaron Anderson: Formal analysis, Writing - review &
editing. Keith Carlisle: Writing - review & editing. Stephanie A.
Shwiff: Conceptualization.

Appendix

Table A-1
Wild pigs Presence in County and on Operation in the Last Three Years.
In county

Alabama
Arkansas
California
Florida
Georgia
Louisiana
Mississippi
Missouri

On operation

Yes

don’t know

No

Yes

don’t know

No

0.61
(0.05)
0.61
(0.10)
0.31
(0.02)
0.62
(0.04)
0.78
(0.03)
0.73
(0.05)
0.70
(0.05)
0.08
(0.03)

0.09
(0.02)
0.09
(0.03)
0.18
(0.02)
0.19
(0.04)
0.06
(0.02)
0.10
(0.03)
0.10
(0.03)
0.29
(0.06)

0.29
(0.05)
0.30
(0.10)
0.51
(0.03)
0.19
(0.03)
0.16
(0.03)
0.17
(0.04)
0.20
(0.04)
0.63
(0.06)

0.35
(0.05)
0.38
(0.08)
0.12
(0.02)
0.38
(0.04)
0.51
(0.04)
0.57
(0.06)
0.30
(0.04)
0.01
(0.00)

0.03
(0.01)
0.19
(0.11)
0.02
(0.01)
0.05
(0.03)
0.02
(0.01)
0.04
(0.02)
0.05
(0.02)
0.01
(0.01)

0.62
(0.05)
0.43
(0.08)
0.85
(0.02)
0.57
(0.04)
0.47
(0.04)
0.39
(0.05)
0.65
(0.05)
0.98
(0.01)
(continued on next page)

10

S. McKee et al.

Crop Protection 132 (2020) 105105

Table A-1 (continued )
In county

North Carolina
Oklahoma
South Carolina
Texas
Total

On operation

Yes

don’t know

No

Yes

don’t know

No

0.36
(0.05)
0.85
(0.03)
0.67
(0.05)
0.91
(0.02)

0.16
(0.03)
0.08
(0.02)
0.11
(0.03)
0.02
(0.01)

0.48
(0.05)
0.07
(0.02)
0.22
(0.04)
0.07
(0.02)

0.10
(0.03)
0.67
(0.04)
0.36
(0.05)
0.78
(0.03)

0.03
(0.01)
0.01
(0.01)
0.02
(0.01)
0.01
(0.01)

0.86
(0.03)
0.32
(0.04)
0.62
(0.05)
0.21
(0.03)

0.59
(0.01)

0.12
(0.01)

0.29
(0.01)

0.38
(0.01)

0.03
(0.01)

0.59
(0.01)

Note: Values are expressed as a fraction of the weighted number of responses in a category to the weighted total of number of responses. Standard errors in parentheses.
Table A-2
Fraction from Each State Reporting Presence on Land and Damage.
Alabama
Arkansas
California
Florida
Georgia
Louisiana
Mississippi
Missouri
North Carolina
Oklahoma
South Carolina
Texas
Total

Present on land

More costly to harvest

Crop damage

Property damage

0.35
(0.05)
0.41
(0.08)
0.08
(0.02)
0.35
(0.05)
0.47
(0.04)
0.54
(0.07)
0.26
(0.05)
0.01
(0.00)
0.12
(0.04)
0.58
(0.05)
0.31
(0.05)
0.70
(0.04)

0.26
(0.05)
0.27
(0.08)
0.04
(0.01)
0.21
(0.04)
0.31
(0.04)
0.34
(0.06)
0.18
(0.04)
0.00
(0.00)
0.08
(0.04)
0.44
(0.05)
0.26
(0.05)
0.55
(0.04)

0.31
(0.05)
0.31
(0.08)
0.04
(0.01)
0.29
(0.05)
0.39
(0.04)
0.37
(0.06)
0.20
(0.05)
0.00
(0.00)
0.10
(0.04)
0.49
(0.05)
0.28
(0.05)
0.59
(0.04)

0.34
(0.05)
0.27
(0.07)
0.11
(0.02)
0.29
(0.04)
0.43
(0.04)
0.51
(0.06)
0.29
(0.05)
0.00
(0.00)
0.10
(0.03)
0.65
(0.04)
0.31
(0.05)
0.73
(0.03)

0.33
(0.01)

0.23
(0.01)

0.29
(0.01)

0.33
(0.01)

Note: Values are expressed as a fraction of the weighted number of responses in a category to the weighted total of number of responses. Standard errors
in parentheses.
Table A-3
Number of Usable Observations.
State
Alabama
Arkansas
California
Florida
Georgia
Louisiana
Mississippi
Missouri
North Carolina
Oklahoma
South Carolina
Texas

Hay, haylage

Tree nuts

Melons

Sugarcane

Sweet potatoes

Cotton

Grapes

Lettuce

Strawberry

43
40
92
47
61
27
56
70
35
118
58
108

24
10
346
25
61
19
7
2
11
20
13
72

5
3
NA
7
7
3
1
4
4
3
8
13

0
0
NA
4
0
16
0
0
0
1
4
4

4
1
NA
1
4
2
6
1
37
1
3
1

56
19
NA
14
71
8
20
20
31
34
27
54

NA
NA
380
NA
NA
NA
NA
NA
NA
NA
NA
NA

NA
NA
7
NA
NA
NA
NA
NA
NA
NA
NA
NA

NA
NA
17
NA
NA
NA
NA
NA
NA
NA
NA
NA

11

S. McKee et al.

Crop Protection 132 (2020) 105105

Table A-4
Fraction from Each State Reporting Control and Willingness to Use Poison ( ).Anderson et al., 2016
State

Attempt to
control

Shooting on
sight

Hunting
with dogs

Hunting
without dogs

Aerial
gunning

Trapping
removing

Repellents

Other

Electric
fencing

Non- electric
fencing

Willing to
use poison

AL

0.34
(0.05)
0.26
(0.07)
0.14
(0.02)
0.32
(0.04)
0.42
(0.04)
0.51
(0.06)
0.27
(0.04)
0.05
(0.03)
0.09
(0.03)
0.55
(0.05)
0.33
(0.06)
0.75
(0.03)

0.25
(0.04)
0.17
(0.05)
0.08
(0.02)
0.26
(0.03)
0.38
(0.04)
0.45
(0.06)
0.20
(0.04)
0.01
(0.01)
0.07
(0.03)
0.45
(0.04)
0.23
(0.05)
0.65
(0.03)

0.03
(0.01)
0.04
(0.03)
0.01
(0.00)
0.13
(0.03)
0.16
(0.03)
0.09
(0.03)
0.05
(0.03)
0.00
–
0.06
(0.03)
0.10
(0.02)
0.13
(0.05)
0.13
(0.02)

0.12
(0.03)
0.06
(0.03)
0.05
(0.01)
0.16
(0.03)
0.24
(0.03)
0.28
(0.06)
0.11
(0.03)
0.00
(0.00)
0.05
(0.02)
0.24
(0.04)
0.16
(0.05)
0.42
(0.04)

0.02
(0.01)
0.02
(0.01)
0.02
(0.01)
0.00
–
0.01
(0.00)
0.00
(0.00)
0.03
(0.02)
0.00
(0.00)
0.07
(0.02)
–
–
0.00
(0.00)
0.04
(0.01)

0.19
(0.81)
0.17
(0.06)
0.05
(0.02)
0.15
(0.03)
0.20
(0.03)
0.25
(0.05)
0.09
(0.03)
0.00
–
0.03
(0.02)
0.33
(0.04)
0.19
(0.05)
0.36
(0.03)

0.01
(0.99)
0.01
(0.01)
0.01
(0.01)
0.00
(0.00)
0.01
(0.01)
0.00
(0.00)
0.04
(0.02)
0.00
–
0.00
(0.00)
0.01
(0.00)
0.02
(0.01)
0.01
(0.01)

0.02
(0.98)
0.01
(0.00)
0.01
(0.00)
0.01
(0.00)
0.01
(0.00)
0.00
(0.01)
0.01
(0.00)
0.00
–
0.00
(0.02)
0.03
(0.02)
0.01
(0.01)
0.04
(0.01)

0.09
(0.91)
0.11
(0.06)
0.01
(0.01)
0.03
(0.02)
0.04
(0.02)
0.04
(0.01)
0.02
(0.01)
0.03
(0.02)
0.00
(0.00)
0.05
(0.02)
0.07
(0.03)
0.11
(0.02)

0.03
(0.97)
0.09
(0.06)
0.07
(0.02)
0.04
(0.01)
0.02
(0.01)
0.02
(0.01)
0.03
(0.01)
0.02
(0.02)
0.00
(0.00)
0.03
(0.02)
0.04
(0.03)
0.17
(0.03)

0.68
(0.05)
0.43
(0.08)
0.35
(0.03)
0.42
(0.04)
0.69
(0.04)
0.77
(0.04)
0.70
(0.04)
0.45
(0.06)
0.59
(0.05)
0.67
(0.04)
0.59
(0.05)
0.68
(0.03)

0.34
(0.01)

0.26
(0.01)

0.07
(0.01)

0.16
(0.01)

0.02
(0.00)

0.16
(0.01)

0.01
(0.00)

0.01
(0.00)

0.04
(0.01)

0.06
(0.01)

0.55
(0.01)

AR
CA
FL
GA
LA
MS
MO
NC
OK
SC
TX
Total

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12