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Effectiveness of contemporary techniques for reducing livestock depredations by large carnivores: Human-Carnivore Coexistence

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Mitigation of large carnivore depredation is essential to increasing stakeholder support for human–carnivore coexistence. Lethal and nonlethal techniques are implemented by managers, livestock producers, and other stakeholders to reduce livestock depredations by large carnivores. However, information regarding the relative effectiveness of techniques commonly used to reduce livestock depredations is currently lacking. We evaluated 66 published, peer-reviewed research papers that quantitatively measured livestock depredation before and after employing 4 categories of lethal and nonlethal mitigation techniques (livestock husbandry, predator deterrents and removal, and indirect management of land or wild prey) to assess their relative effectiveness as livestock protection strategies. Effectiveness of each technique was measured as the reported percent change in livestock losses. Husbandry (42–100% effective) and deterrents (0–100% effective) demonstrated the greatest potential but also the widest variability in effectiveness in reducing livestock losses. Removal of large carnivores never achieved 100% effectiveness but exhibited the lowest variation (67–83%). Although explicit measures of effectiveness were not reported for indirect management, livestock depredations commonly decreased with sparser and greater distances from distant vegetation cover, at greater distances from protected areas, and in areas with greater wild prey abundance. Information on time duration of effects was available only for deterrents; a tradeoff existed between the effectiveness of tools and the length of time a tool remained effective. Our assessment revealed numerous sources of bias regarding the effectiveness of techniques as reported in the peer-reviewed literature, including a lack of replication across species and geographic regions, a focus on Canid carnivores in the United States, Europe, and Africa, and a publication bias toward studies reporting positive effects. Given these limitations, we encourage managers and conservationists to work with livestock producers to more consistently and quantitatively measure and report the impacts of mitigation techniques under a wider range of environmental, economic, and sociological conditions.
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Effectiveness of Contemporary Techniques for Reducing Livestock Depredations by Large
Carnivores
JENNIFER. R. B. MILLER,1,2 Yale School of Forestry and Environmental Studies, 195 Prospect
Street, New Haven, CT 06511, USA
KELLY J. STONER,3 Yale School of Forestry and Environmental Studies, 195 Prospect Street,
New Haven, CT 06511, USA
MIKAEL R. CEJTIN, Yale School of Forestry and Environmental Studies, 195 Prospect Street,
New Haven, CT 06511, USA
TARA K. MEYER,4 Yale School of Forestry and Environmental Studies, 195 Prospect Street,
New Haven, CT 06511, USA
ARTHUR D. MIDDLETON,5 Yale School of Forestry and Environmental Studies, 195 Prospect
Street, New Haven, CT 06511, USA
OSWALD J. SCHMITZ, Yale School of Forestry and Environmental Studies, 195 Prospect
Street, New Haven, CT 06511, USA
1 E-mail: jmiller@panthera.org
2 Present address: Panthera, 8 West 40th Street, 18th Floor, New York, NY 10018, USA; Human
Wildlife Institute, Department of Biological Sciences, University of Cape Town, Private Bag X3,
Rondebosch, Cape Town 7701, South Africa; Department of Natural Resources, Cornell
University, 111 Fernow Hall, Ithaca, NY 14853, USA
3 Present address: Ruaha Carnivore Project, Iringa, Tanzania
4 Present address: Washington Department of Fish and Wildlife, 2108 Grand Boulevard,
Vancouver, WA 98661, USA
5 Present address: Department of Environmental Science, Policy, and Management, Mulford
Hall, University of California Berkeley, Berkeley, CA 94720, USA
*This is the authors’ final submitted version of the article. The final, published version of the
article can be found online: http://onlinelibrary.wiley.com/doi/10.1002/wsb.720/abstract
Citation:
Miller, J.R.B., Stoner, K.J., Cejtin, M.R., Meyer, T.K., Middleton, A.D., Schmitz, O.J. 2016.
Effectiveness of contemporary techniques for reducing livestock depredations by large
carnivores. Wildlife Society Bulletin 40(4): 806–815. doi:10.1002/wsb.720
2 | Miller et al.
ABSTRACT Mitigation of large carnivore depredation is essential to increasing stakeholder
support for human–carnivore coexistence. Lethal and nonlethal techniques are implemented by
managers, livestock producers, and other stakeholders to reduce livestock depredations by large
carnivores. However, information regarding the relative effectiveness of techniques commonly
used to reduce livestock depredations is currently lacking. We evaluated 66 published, peer-
reviewed research papers that quantitatively measured livestock depredation before and after
employing 4 categories of lethal and nonlethal mitigation techniques (livestock husbandry,
predator deterrents and removal, and indirect management of land or wild prey) to assess their
relative effectiveness as livestock protection strategies. Effectiveness of each technique was
measured as the reported percent change in livestock losses. Husbandry (42–100% effective) and
deterrents (0–100% effective) demonstrated the greatest potential but also the widest variability
in effectiveness in reducing livestock losses. Removal of large carnivores never achieved 100%
effectiveness but exhibited the lowest variation (67–83%). Although explicit measures of
effectiveness were not reported for indirect management, livestock depredations commonly
decreased with sparser and greater distances from distant vegetation cover, at greater distances
from protected areas, and in areas with greater wild prey abundance. Information on time
duration of effects was available only for deterrents; a tradeoff existed between the effectiveness
of tools and the length of time a tool remained effective. Our assessment revealed numerous
sources of bias regarding the effectiveness of techniques as reported in the peer-reviewed
literature, including a lack of replication across species and geographic regions, a focus on Canid
carnivores in the United States, Europe, and Africa, and a publication bias toward studies
reporting positive effects. Given these limitations, we encourage managers and conservationists
to work with livestock producers to more consistently and quantitatively measure and report the
impacts of mitigation techniques under a wider range of environmental, economic, and
sociological conditions.
KEY WORDS human–carnivore coexistence, human–wildlife conflict, large carnivore
conservation, lethal control, nonlethal management.
Large carnivore species are common priorities for landscape-scale conservation because of their
importance as keystone drivers of ecosystem function, revered cultural symbols, and susceptible
targets of extinction threats (Di Minin et al. 2016). Of the 31 largest terrestrial carnivores (body
mass >15 kg, Ripple et al. 2014; Table S1 in Supporting Information Appendix 1, available
online at www.onlinelibrary.wiley.com), most (77%) are undergoing continued population
declines and many (61%) are listed by the International Union for the Conservation of Nature as
vulnerable, endangered, or critically endangered and threatened with local or global extinction
(Ripple et al. 2014). The loss of large carnivore species can destabilize ecological and human
communities by altering the structure of food webs, disrupting ecosystem services, and
exacerbating social conflicts between people through the decrease or redistribution of natural
resources (Brashares et al. 2014, Ripple et al. 2014). Declines in these valuable species are due to
3 | Miller et al.
a suite of biological traits, including large body size, high energy constraints, large area
requirements, low densities, and slow population growth rates, compounded by exposure to
anthropogenic threats such as habitat degradation and fragmentation, loss of prey, persecution,
and overexploitation by humans (Cardillo et al. 2004, Marshall et al. 2015). Many of these
anthropogenic threats are facilitated by human–carnivore conflict, often stemming from the need
to stop carnivores from attacking livestock and affecting human livelihoods.
Large carnivore livestock depredations can result in substantial economic hardships for
livestock producers and ultimately weaken local support for conservation (Wang and Macdonald
2006, Lindsey et al. 2013). Stakeholders tend to hold especially negative attitudes toward large
carnivores in part because of predators’ reputation for attacking large-bodied, high-value
livestock. Livestock depredation can undermine stakeholder support for conservation as a whole
as well as result in retaliatory killing of predators by livestock owners (Treves and Karanth 2003,
Baker et al. 2008, Inskip and Zimmermann 2009). Reducing conflict between large carnivores
and livestock is thus critical for maintaining viable ecosystems and the human communities that
depend on them.
Global stakeholder interest in reducing large carnivore depredation on livestock has led to
the development of numerous mitigation techniques. These include preventive husbandry (e.g.,
guard dogs or fencing), deterrents (e.g., light–sound devices or shock collars), removal
(translocation or lethal population–problem animal control), and indirect management of land
(e.g., habitat improvements, zoning for designated land uses and protected areas) and wildlife
(e.g., increasing the wild prey base; Shivik 2006, Linnell et al. 2012). Effective implementation
of these techniques can reduce large carnivore attacks on livestock depredations and encourage
species conservation (Hazzah et al. 2014, Lichtenfeld et al. 2014).
Human–carnivore conflicts are complex and shaped by a suite of cultural, economic,
historical, and ecological factors that may affect the use and effectiveness of techniques for
mitigating livestock depredations (Messmer 2000, Messmer et al. 2001, Dickman 2010).
Previous syntheses of the published literature have discussed the relative advantages and
disadvantages of different techniques, but have not quantitatively compared or contrasted
situational effectiveness (Breitenmoser et al. 2005, Shivik 2006, Sillero-Zubiri et al. 2007, Inskip
and Zimmermann 2009, Pettigrew et al. 2012, Redpath et al. 2012). There is currently no
consensus as to which techniques are most useful and under what circumstances, or on the
associated tradeoffs between time duration and effectiveness level. This information could assist
stakeholders in selecting objective-based strategies that optimize livestock protection benefits.
To evaluate the relative effectiveness of techniques used to mitigate livestock depredation by
large wild carnivores, we compared the results of quantitative studies of technique effectiveness
(i.e., percent change in livestock losses or carnivore behavior and the duration of the effects) as
reported in the peer-reviewed scientific literature. We examined the utility of each technique
based on its effectiveness in reducing livestock losses in an attempt to identify patterns of use
that might facilitate more informed selection by potential users.
4 | Miller et al.
METHODS
Literature Search
We searched Web of Science (www.webofknowledge.com) and the database Carnivore Ecology
and Conservation (www.carnivoreconservation.org) for peer-reviewed articles that examined
techniques for reducing depredations of livestock by wild large carnivores. We used compound
search terms that included the technique (e.g., deterrent) or a specific tool (e.g., aversive stimuli
or behavior conditioning; see Table 1) plus 1 of 7 general keywords related to livestock
depredation conflict (human–carnivore conflict, livestock depredation, human–carnivore
coexistence, mitigation, depredation management, depredation prevention, or depredation
control). We defined a large carnivore as one with body mass >15 kg (Ripple et al. 2014). Our
searches followed the formula: (technique or tool name) and (conflict keyword); for example,
“deterrent human carnivore conflict” or “aversive stimuli livestock depredation.” We found
additional literature that matched our criteria by reviewing articles cited in the articles from our
searches that seemed relevant from their title or context in the article (snowball sampling;
Goodman 1961).
We assessed only primary literature in English that provided numeric metrics (or values
for calculating numeric metrics) of effectiveness; reviews were omitted from analysis. We
defined effectiveness as the change in livestock losses or the potential for an attack (e.g., percent
reduction in livestock losses or carnivore visits to a pasture) after techniques were applied. In
addition to measures of effectiveness, we also recorded the amount of time that techniques were
effective in reducing depredation if available. We noted articles that analyzed correlations
between the implementation of tools and livestock depredation to supplement our analysis of the
effectiveness of different tools. We recorded the large carnivore species involved and the country
where the study occurred for each article.
Data analysis
We compared the effectiveness of techniques by calculating the magnitude of change between
conditions before and after a technique was applied. We calculated the magnitude of change (D)
as the percentage deviation from initial conditions following the formula (adapted from Jones
and Schmitz 2009):
[ ]
( )
/ 100DBAB=− ×
where B represents a quantitative measure of conditions (the change in livestock losses or the
potential for an attack; e.g., no. of livestock killed) before the mitigation technique was applied
and A represents conditions after the technique was applied. We compared the differences
between magnitudes of change among techniques using boxplots.
This metric afforded a common basis for comparing different techniques by standardizing
measures of change in terms of a proportion to facilitate data integration from different studies
that used different units in their response metrics. Units from articles were most commonly
expressed in terms of livestock depredation (e.g., no. of livestock lost or no. of farms with
5 | Miller et al.
depredation; original units reported by articles are listed in Table S2). If a study reported the
effectiveness of a technique on a community of predators (e.g., guard dog effects on combined
rates of depredation by brown bear [Ursus arctos], gray wolf [Canis lupus], and Eurasian lynx
[Lynx lynx]; Otstavel et al. 2009), we reported the effectiveness for the predator community as a
whole.
RESULTS
Our literature search yielded 66 articles that matched our criteria (Supporting Information
Appendix 1). These articles primarily assessed husbandry (39% of articles), followed by indirect
management (26%), deterrents (23%), and removal (20%; percentages reported in this section
exceed 100% because some articles addressed >1 category). An equal number of articles
reported on the effectiveness of techniques (measured numerically before and after
implementation) as on the associations between technique use and depredation (correlation
statistics), and 4% of articles reported both metrics. Both metrics were reported in relatively
comparable proportions in articles on husbandry (54% of articles reported effectiveness, 46%
correlations) and removal (50% effectiveness, 67% correlations), but articles on deterrents
exclusively reported effectiveness while articles on indirect management reported only
correlations. The time duration of effects was explored in 20% of articles, all of which focused
on deterrents.
Articles addressed 16 large carnivore species (59% of all species investigated; Table S1)
across 27 countries and 6 continents (Fig. S1). Gray wolf was the most studied species (38% of
articles), followed by lion (Panthera leo, 14%), brown bear (12%), American black bear (U.
americanus, 12%), leopard (P. pardus, 11%), Eurasian lynx (11%), and puma (Puma concolor,
9%; Fig. S1A). The number of articles featuring Canids (47%) nearly equaled those on Felids
(42%), and fewer studies examined Ursids (26%) and Hyaenids (5%). Twenty-five percent of the
articles described the effects of techniques on multiple predators (2–5 species). Articles revealed
a publication bias in favor of species located in North America (39%; primarily in the United
States [33% of all articles]), Europe (23%; primarily in Norway [8%]), and Africa (18%;
primarily in Kenya [6%]; Fig. S1B).
Technique Effectiveness
Husbandry reduced livestock depredation by between 42% and 100% (note that one outlier
reported 3% effectiveness; Hansen and Smith 1999; Fig. 1A). The effectiveness of guard dogs
ranged from 3–100% (n = 7 studies), electric fences from 58–100% (n = 2), night enclosures
from 50% to 89% (n = 4), and non-electric fences from 51% to 78% (n = 2), and human guards
were 70% effective (note that n = 1; Fig. 1B). Correlation studies revealed that enclosing
livestock at night, as well as the presence of human and animal guards, was associated with
decreased depredation, but that the abundance of livestock (total no. or density) had mixed
effects on depredation (Table 2). Articles on husbandry mainly investigated depredation by
Canids (56%) and Felids (50%), with less than one-third of studies on Ursids (23%) and Hyenids
6 | Miller et al.
(11%; percentages exceed 100 because some articles addressed multiple species). Articles
explored effects on 2 or 3 carnivore species except for livestock night enclosures, which were
tested on 4 species (brown bear, gray wolf, lion, puma), and guard dogs, which were tested on 8
species (American black bear, brown bear, cheetah [Acinonyx jubatus], dingo [Canis lupus
dingo], Eurasian lynx, gray wolf, puma, spotted hyena [Crocuta crocuta]; Fig. 1B).
Carnivore removal showed the least overall variation, with 5 out of 6 articles reporting
67–83% effectiveness (Fig. 1A; note that one outlier on leopard translocation reported an
increase in livestock depredation by 56%; Athreya et al. 2010). Most removal studies focused on
translocation (5 of 6 articles). Correlation studies on translocations reported fewer depredations
by lions (Stander 1990) but not by brown bears (Sagor et al. 1997). Lethal population control of
carnivores was quantitatively measured by only one study, which reported 68% effectiveness
with black-backed jackal (Canis mesomelas), caracal (Caracal caracal), and leopard (McManus
et al. 2014; Fig. 1B). Lethal control was associated with decreases in depredation by brown bear,
dingo, and Eurasian lynx but had no effect on livestock killed by Asiatic black bear (U.
thibetanus) or gray wolf (Table 2). Removal studies examined Felids (50% of removal studies),
Ursids (33%), and Canids (25%), but no Hyenid species.
Carnivore deterrents overall demonstrated wide variation, ranging from 0% to 100% in
effectiveness, although most tools (75%) reduced depredation by 30%. In contrast to preventive
husbandry techniques, where a single tool was often effective on multiple carnivore species,
deterrent tools were usually tested on a single species (Fig. 1A). The most effective deterrents
were electrified fladry (100% effective, but note that n = 1), light and sound devices (79–100%;
n = 2), and shock collars (50–87%; n = 5); these were tested only on gray wolves (Fig. 1B).
Chemicals were highly effective in deterring brown bears (89%) but less effective for American
black bears (47%) and polar bears (U. maritimus; 2%; n = 2). Combining multiple deterrents
(sounds, chemicals, rubber bullets, and guard dogs) did not deter American black bears (8%;
note that n = 1); however, the effects were longer lasting than any other combination of
deterrents tested (Fig. 2). Studies involving deterrent techniques examined Canids (50% of
articles) and Ursids (47%) but not Felids or Hyaenids.
No quantitative measures of effectiveness were available for assessing indirect
management but correlation-based studies revealed associations with several environmental
factors (Table 2). Distance to vegetation cover was associated with the number of livestock
losses, with more depredations occurring closer to cover for Eurasian lynx, jaguar (P. onca), lion,
puma, and spotted hyena (Stahl et al. 2002, Ogada et al. 2003, Michalski et al. 2006, Gusset et al.
2009) and farther from cover for gray wolf (Treves et al. 2011). Sites with more vegetation cover
reported greater rates of livestock depredation by African wild dog (Lycaon pictus), brown bear,
jaguar, leopard, puma, and spotted hyena (Wilson et al. 2005, Woodroffe et al. 2006, Zarco-
González et al. 2013). Closer proximity to a protected area was associated with an increased
chance of livestock attacks by leopard, tiger (P. tigris), and spotted hyena (Gusset et al. 2009,
Karanth et al. 2013) but showed positive and negative associations for lion (Van Bommel et al.
2007, Gusset et al. 2009). High abundance of wild prey correlated with fewer depredations by
7 | Miller et al.
African wild dog (Woodroffe et al. 2005; Table 2), gray wolf, and lion (Gula 2008, Valeix et al.
2012), but varied for Eurasian lynx and snow leopards (Uncia uncia; Stahl et al. 2002; Bagchi
and Mishra 2006; Odden et al. 2008, 2013; Suryawanshi et al. 2013). Articles on indirect
management primarily examined Felids (78%), followed by Canids (28%), Hyenids (11%), and
Ursids (6%).
Time Duration of Effectiveness
Data on time duration were only reported for deterrents and by a small number of studies (n =
13). Chemical repellents (n = 2) had the longest lasting effects on carnivores but the duration of
effects from these tools varied widely, with some tools deterring carnivores permanently and
others for only 5 minutes (Fig. 1A; Table S2). The use of multiple deterrents (note that n = 1)
and shock collars (n = 4) also showed long-term effects, preventing revisits for 21 and 17
months, respectively. Advanced technology did not necessarily improve the longevity of tool
effectiveness. For example, non-electrified fladry lasted up to 6 times longer than electric fladry
(90 compared with 14 days, where n = 3 and n = 1, respectively). Acoustics (n = 2) had the
briefest effect on carnivore behavior, deterring bears 1–3 days at most. When comparing
deterrents by the time and level of effectiveness, tools that ranked highest on both scales were
shock collars (tested only on gray wolves) and chemical repellents (tested only on Ursid species;
Fig. 1B; Table S2). Electric fladry and light–sound devices decreased depredation (>80%) over
short periods (2 months). Acoustics ranked low on both scales (5% effective for up to 3 days).
Note that because some tools were tested during timed trials, which measured the minimum time
length of effectiveness, values from these studies likely underestimated the length of time that
tools remain effective (Fig. 2).
DISCUSSION
Our review revealed high variability in the reported effectiveness of techniques for reducing
livestock depredation across a range of large carnivore species, geographic locations, and
environmental conditions. Across all techniques, husbandry and deterrents showed the greatest
upper limits of effectiveness in reducing livestock losses; removal showed the least variation.
Several tools consistently demonstrated great effectiveness (50% change) across
multiple studies: light–sound devices, night enclosures, shock collars, electric and non-electric
fences, and translocation. Electrified fladry, human guards, and lethal control demonstrated high
effectiveness in a single study but require further testing to explore consistency. The
effectiveness of non-electrified fladry varied across one carnivore species (gray wolves),
suggesting that this method may be highly sensitive to field conditions or prone to problems with
implementation. In contrast, the effectiveness of guard dogs, acoustics, and chemical repellents
varied across different carnivore species, indicating that the success of these tools may be limited
to a few species. All the tools in our assessment reduced depredation by some positive measure
except for non-electrified fladry, where one study had no effect, and translocation, where one
study increased conflict, reportedly because of behavioral changes after leopards were
8 | Miller et al.
translocated to sites where residential leopards held pre-established territories (Athreya et al.
2010). Considering the low sample size of studies for carnivore removal, as well as evidence of
translocation increasing conflict, carnivore removal should be implemented with close
monitoring and more rigorous testing to determine whether the necessary resources and potential
impacts on the broader ecosystem are worthwhile (Treves and Karanth 2003, Herfindal et al.
2005).
For deterrents, where the time length of effects was measured consistently across studies,
a tradeoff appears to exist between the effectiveness of tools in reducing livestock losses and the
length of time a tool remains effective. Tools with the greatest effectiveness often lasted for only
a few hours, weeks, or months. These results match the findings of other reviews (Breitenmoser
et al. 2005, Shivik 2006) and indicate that deterrents may be most optimally implemented during
brief times of high risk, such as the calving or lambing season (Schultz et al. 2005), when short-
term protection would achieve the greatest financial benefits. Assessments of the time duration
of effects from preventative husbandry, carnivore removal, and indirect management are needed
to weigh tradeoffs between effectiveness level and duration for these techniques.
We found some evidence to suggest that combining techniques may increase the
longevity of effects by providing different types of stimuli and protecting against multiple
carnivore species. If the effectiveness of tools in our assessment holds when multiple techniques
are combined, an optimal strategy for protecting livestock across carnivore species and systems
could be to implement a baseline of preventative husbandry (e.g., electric fences with animal or
human guards) supplemented by deterrents to briefly boost effectiveness during key times (e.g.,
shock collars and sound–light devices) and the use of translocation or lethal control when
specific problem animals are identified. Though the effectiveness levels of indirect management
of land use and wild prey have not yet been measured quantitatively, environmental conditions
and prey availability have direct ties to livestock depredation and should also be managed to
reduce the likelihood of livestock loss (Inskip and Zimmermann 2009, Linnell et al. 2012,
Pettigrew et al. 2012).
We encountered several inherent biases in the peer-review literature that constrained our
ability to compare effectiveness evenly across techniques. One-third of techniques reported in
the literature were tested by only one study, with techniques that were often repeatedly tested on
a single carnivore species. Articles also focused heavily on Canid carnivores in the United States,
Europe, and Africa. These biases toward species and locations prevented us from drawing
general conclusions about the effectiveness of techniques or tools on carnivore species or
locations.
Our analysis could have been affected by a publication bias toward positive effects
(Møller and Jennions 2001), which may have reduced the number of published articles reporting
low or no effectiveness of techniques. Also, the articles we reviewed were inevitably biased
toward recently published articles (95% were published after 1995), which are more often
indexed in search engines than older papers. Though our assessment represents the best available
quantitative comparison of technique effectiveness in the peer-review literature, these biases
9 | Miller et al.
should be considered when applying our results to select the most optimal livestock-depredation
mitigation techniques.
Though the literature on human–carnivore conflict has greatly matured over the past
decade, one of our most important observations was the lack of frequency, consistency, and
depth in how livestock depredation mitigation efforts were measured and evaluated in the
scientific literature (Graham et al. 2005). Measuring rates of depredation before and after
implementing mitigation techniques and the time duration of effects is critical for understanding
and comparing effectiveness among methods. It may be that these types of studies have been
published more extensively as grey literature, such as government agency reports or educational
pamphlets for landowners, but not evaluated through peer-review. The call for consistent
measures and rigorous assessment has been repeatedly sounded before (Graham et al. 2005,
Inskip and Zimmermann 2009); therefore, we suggest that concerted funding and policy
initiatives may now be necessary to fill the existing knowledge gaps if conflict management
techniques are to become more efficient and effective worldwide.
MANAGEMENT IMPLICATIONS
We compared mitigation techniques by their reported effectiveness, but we encourage future
studies to also consider examining other important indicators of human–carnivore coexistence
such as carnivore population size, livestock producer attitudes toward carnivores, and broader
effects on the environment. We also encourage researchers to partner with livestock producers to
take advantage of real-world conditions where depredation mitigation is needed. Priority should
be given to testing the effectiveness of human guards, indirect management of land use and wild
prey, and lethal carnivore population control because these techniques can involve large financial
and time costs and have detrimental impacts on carnivore populations and ecosystems,
sometimes without realized reductions in human–carnivore conflict. Lethal population control
especially warrants attention because it is used so commonly and yet its effectiveness is poorly
studied. Finally, economic analyses of the tradeoffs between effectiveness and cost are also
critically needed to help stakeholders weigh the financial burdens of implementing mitigation
techniques. As we continue to improve our base of quantitative, evidence-based insight, we will
ultimately strengthen our ability to reduce livestock losses, prevent retaliations against predators,
and achieve more sustainable coexistence between people and carnivores.
ACKNOWLEDGMENTS
This article was motivated by discussions at the 2013 Yale Carnivore Conservation Symposium.
We thank S. Clark, G. Balme, N. Jayasinghe, T. Messmer, and several anonymous reviewers for
valuable feedback on this manuscript. We especially wish to thank the conservationists,
managers, and livestock producers across the world dedicated to reducing conflict and pursuing
coexistence between people and carnivores.
10 | Miller et al.
SUPPORTING INFORMATION
Additional supporting information may be found in the online version of this article at the
publisher’s web-site. The supporting information consists of Supporting Information Appendix 1,
which includes,
Table S1. Large carnivore species with body mass >15 kg included in the review.
Table S2. Data and original units from articles used in Figure 2 on technique effectiveness.
Figure S1. Number of assessed articles by (A) large carnivore species and (B) country.
Appendix 1. Articles included in the assessment.
LITERATURE CITED
Allen, L. R., and E. C. Sparkes. 2001. The effect of dingo control on sheep and beef cattle in
Queensland. Journal of Applied Ecology 38:76–87.
Anderson, C. R., M. A. Ternent, and D. S. Moody. 2002. Grizzly bear-cattle interactions on two
grazing allotments in northwest Wyoming. Ursus 13:247–256.
Athreya, V. R., M. Odden, J. D. C. Linnell, and K. U. Karanth. 2010. Translocation as a tool for
mitigating conflict with leopards in human-dominated landscapes of India. Conservation
Biology 25:133–141.
Azevedo, F. C. C. De, and D. L. Murray. 2007. Evaluation of potential factors predisposing
livestock to predation by jaguars. Journal of Wildlife Management 71:2379–2386.
Bagchi, S., and C. Mishra. 2006. Living with large carnivores: predation on livestock by the
snow leopard (Uncia uncia). Journal of Zoology 268:217–224.
Baker, P. J., L. Boitani, S. Harris, G. Saunders, and P. C. L. White. 2008. Terrestrial carnivores
and human food production: impact and management. Mammal Review 38:123–166.
Bradley, E. H., and D. H. Pletscher. 2005. Assessing factors related to wolf depredation of cattle
in fenced pastures in Montana and Idaho. Wildlife Society Bulletin 33:1256–1265.
Brashares, J. S., B. Abrahms, K. J. Fiorella, D. Christopher, C. E. Hojnowski, R. A. Marsh, D. J.
Mccauley, T. A. Nuñez, K. Seto, and L. Withey. 2014. Wildlife decline and social
conflict. Science 345:376–378.
Breck, S. W., B. M. Kluever, M. Panasci, J. Oakleaf, T. Johnson, W. Ballard, L. D. Howery, and
D. L. Bergman. 2011. Domestic calf mortality and producer detection rates in the
Mexican wolf recovery area: implications for livestock management and carnivore
compensation schemes. Biological Conservation 144:930–936.
Breitenmoser, U., C. Angst, J.-M. Landry, C. Breitenmoser-Wursten, J. D. C. Linnell, and J.-M.
Weber. 2005. Non-lethal techniques for reducing depredation. Pages 49–71 in R.
Woodroffe, S. Thirgood, and A. Rabinowitz, editors. People and wildlife: conflict or
coexistence? Cambridge University Press, Cambridge, England, United Kingdom.
Cardillo, M., A. Purvis, W. Sechrest, J. L. Gittleman, J. Bielby, and G. M. Mace. 2004. Human
population density and extinction risk in the world’s carnivores. PLoS Biology 2:909–
914.
Dickman, A. J. 2010. Complexities of conflict: the importance of considering social factors for
11 | Miller et al.
effectively resolving human–wildlife conflict. Animal Conservation 13:458–466.
Di Minin, E., R. Slotow, L. T. B. Hunter, F. Montesino Pouzols, T. Toivonen, P. H. Verburg, N.
Leader-Williams, L. Petracca, and A. Moilanen. 2016. Global priorities for national
carnivore conservation under land use change. Scientific Reports 6:23814.
Espuno, N., B. Lequette, M.-L. L. Poulle, P. Migot, and J.-D. Lebreton. 2004. Heterogeneous
response to preventive sheep husbandry during wolf recolonization of the French Alps.
Wildlife Society Bulletin 32:1195–1208.
Goodman, L. 1961. Snowball sampling. Annals of Math Statistics 32:148–170.
Graham, K., A. P. Beckerman, and S. Thirgood. 2005. Human–predator–prey conflicts:
ecological correlates, prey losses and patterns of management. Biological Conservation
122:159–171.
Gula, R. 2008. Wolf depredation on domestic animals in the Polish Carpathian Mountains.
Journal of Wildlife Management 72:283–289.
Gusset, M., M. J. Swarner, L. Mponwane, K. Keletile, and J. W. McNutt. 2009. Human–wildlife
conflict in northern Botswana: livestock predation by Endangered African wild dog. Oryx
43:67–72.
Hansen, I., and M. E. Smith. 1999. Livestock-guarding dogs in Norway Part II: different working
regimes. Journal of Range Management 52:312–316.
Harper, E., W. J. Paul, L. D. Mech, and S. Weisberg. 2008. Effectiveness of lethal, directed
wolf-depredation control in Minnesota. Journal of Wildlife Management 72:778–784.
Hazzah, L., S. Dolrenry, L. Naughton, C. T. T. Edwards, O. Mwebi, F. Kearney, and L. Frank.
2014. Efficacy of two lion conservation programs in Maasailand, Kenya. Conservation
Biology 28:851–860.
Herfindal, I., J. D. C. Linnell, P. F. Å. L. F. Moa, J. Odden, L. B. Austmo, and R. Andersen.
2005. Does recreational hunting of lynx reduce depredation losses of domestic sheep?
Journal of Wildlife Management 69:1034–1042.
Huygens, O. C., F. T. van Manen, D. A. Martorello, H. Hayashi, and J. Ishida. 2004.
Relationships between Asiatic black bear kills and depredation costs in Nagano
Prefecture, Japan. Ursus 15:197–202.
Iliopoulos, Y., S. Sgardelis, V. Koutis, and D. Savaris. 2009. Wolf depredation on livestock in
central Greece. 54:11–22.
Inskip, C., and A. Zimmermann. 2009. Human–felid conflict: a review of patterns and priorities
worldwide. Oryx 43:18–35.
Jones, H. P., and O. J. Schmitz. 2009. Rapid recovery of damaged ecosystems. PloS ONE
4:e5653.
Karanth, K. K., L. Naughton-Treves, R. S. DeFries, and A. M. Gopalaswamy. 2013. Living with
wildlife and mitigating conflicts around three Indian protected areas. Environmental
Management 52:1320–1332.
Kolowski, J., and K. E. K. Holekamp. 2006. Spatial, temporal, and physical characteristics of
livestock depredations by large carnivores along a Kenyan reserve border. Biological
12 | Miller et al.
Conservation 128:529–541.
Lichtenfeld, L. L., C. Trout, and E. L. Kisimir. 2014. Evidence-based conservation: predator-
proof bomas protect livestock and lions. Biodiversity and Conservation 24:483–491.
Lindsey, P. A., C. P. Havemann, R. Lines, L. Palazy, A. E. Price, T. A. Retief, T. Rhebergen,
and C. Van der Waal. 2013. Determinants of persistence and tolerance of carnivores on
Namibian ranches: implications for conservation on Southern African private lands. PloS
ONE 8:e52458.
Linnell, J. D. C., J. Odden, and A. Mertens. 2012. Mitigation methods for conflicts associated
with carnivore depredation on livestock. Pages 314–332 in L. Boitani and R. A. Powell,
editors. Carnivore ecology and conservation: handbook of techniques. Oxford University
Press, Oxford, England, United Kingdom.
Marshall, K. N., A. C. Stier, J. F. Samhouri, R. P. Kelly, and E. J. Ward. 2015. Conservation
challenges of predator recovery. Conservation Letters 9:70–78.
McManus, J. S., A. J. Dickman, D. Gaynor, B. H. Smuts, and D. W. Macdonald. 2014. Dead or
alive? Comparing costs and benefits of lethal and non-lethal human–wildlife conflict
mitigation on livestock farms. Oryx 49:687–695.
Mech, L. D., E. K. Harper, T. J. Meier, and W. J. Paul. 2000. Assessing factors that may
predispose Minnesota farms to wolf depredations on cattle. Wildlife Society Bulletin
28:623–629.
Messmer, T. A. 2000. The emergence of human–wildlife conflict management: turning
challenges into opportunities. International Biodeterioration & Biodegradation 45:97–
102.
Messmer, T. A., D. Reiter, and B. C. West. 2001. Enhancing wildlife sciences' linkage to public
policy: lessons from the predator-control pendulum. Wildlife Society Bulletin 29:1253–
1259.
Michalski, F., R. L. P. Boulhosa, A. Faria, and C. A. Peres. 2006. Human–wildlife conflicts in a
fragmented Amazonian forest landscape: determinants of large felid depredation on
livestock. Animal Conservation 9:179–188.
Møller, A. P., and M. D. Jennions. 2001. Testing and adjusting for publication bias. Trends in
Ecology & Evolution 16:580–586.
Odden, J., I. Herfindal, J. D. C. Linnell, and R. Andersen. 2008. Vulnerability of domestic sheep
to lynx depredation in relation to roe deer density. Journal of Wildlife Management
72:276–282.
Odden, J., E. B. Nilsen, and J. D. C. Linnell. 2013. Density of wild prey modulates lynx kill rates
on free-ranging domestic sheep. PloS ONE 8:e79261.
Ogada, M. O., R. Woodroffe, N. O. Oguge, and L. G. Frank. 2003. Limiting depredation by
African carnivores: the role of livestock husbandry. Conservation Biology 17:1521–1530.
Otstavel, T., K. a Vuori, D. E. David, A. Valros, O. Vainio, and H. Saloniemi. 2009. The first
experience of livestock guarding dogs preventing large carnivore damages in Finland.
Estonian Journal of Ecology 58:216.
13 | Miller et al.
Pettigrew, M., Y. Xie, A. Kang, M. Rao, J. M. Goodrich, T. Liu, and J. Berger. 2012. Human–
carnivore conflict in China: a review of current approaches with recommendations for
improved management. Integrative Zoology 7:210–226.
Redpath, S. M., J. Young, A. Evely, W. M. Adams, W. J. Sutherland, A. Whitehouse, A. Amar,
R. A. Lambert, J. D. C. Linnell, A. Watt, and R. J. Gutiérrez. 2012. Understanding and
managing conservation conflicts. Trends in Ecology & Evolution 28:100–109.
Ripple, W. J., J. A. Estes, R. L. Beschta, C. C. Wilmers, E. G. Ritchie, M. Hebblewhite, J.
Berger, B. Elmhagen, M. Letnic, M. P. Nelson, O. J. Schmitz, D. W. Smith, A. D.
Wallach, and A. J. Wirsing. 2014. Status and ecological effects of the world’s largest
carnivores. Science 343:1–11.
Sagor, J. T., J. E. Swenson, and E. Roskaft. 1997. Compatibility of brown bear Ursus arctos and
free-ranging sheep in Norway. Biological Conservation 81:91–95.
Schultz, R., K. W. Jonas, L. H. Skuldt, and A. P. Wydeven. 2005. Experimental use of dog-
training shock collars to deter depredation by gray wolves. Wildlife Society Bulletin
33:142–148.
Shivik, J. A. 2006. Tools for the edge: what’s new for conserving carnivores. BioScience
56:253–259.
Sillero-Zubiri, C., R. Sukumar, and A. Treves. 2007. Living with wildlife: the roots of conflict
and the solutions. Pages 253–270 in D. W. Macdonald and K. Service, editors. Key topics
in conservation biology. Blackwell, Oxford, England, United Kingdom.
Stahl, P., J. M. Vandel, V. Herrenschmidt, and P. Migot. 2001. The effect of removing lynx in
reducing attacks on sheep in the French Jura Mountains. Biological Conservation
101:15–22.
Stahl, P., J. M. Vandel, S. Ruette, L. Coat, Y. Coat, and L. Balestra. 2002. Factors affecting lynx
predation on sheep in the French Jura. Journal of Applied Ecology 39:204–216.
Stander, P. E. 1990. A suggested management strategy for stock-raiding lions in Namibia. South
African Journal of Wildlife Research 20:37–43.
Suryawanshi, K. R., Y. V Bhatnagar, S. Redpath, and C. Mishra. 2013. People, predators and
perceptions: patterns of livestock depredation by snow leopards and wolves. Journal of
Applied Ecology 50:550–560.
Treves, A., and K. U. Karanth. 2003. Human–carnivore conflict and perspectives on carnivore
management worldwide. Conservation Biology 17:1491–1499.
Treves, A., K. A. Martin, A. P. Wydeven, and J. E. Wiedenhoeft. 2011. Forecasting
environmental hazards and the application of risk maps to predator attacks on livestock.
BioScience 61:451–458.
Tumenta, P. N., H. H. de Iongh, P. J. Funston, and H. A. Udo de Haes. 2013. Livestock
depredation and mitigation methods practised by resident and nomadic pastoralists
around Waza National Park, Cameroon. Oryx 47:237–242.
Valeix, M., G. Hemson, A. J. Loveridge, G. Mills, and D. W. Macdonald. 2012. Behavioural
adjustments of a large carnivore to access secondary prey in a human-dominated
14 | Miller et al.
landscape. Journal of Applied Ecology 49:73–81.
Van Bommel, L., M. D. Bij de Vaate, W. F. De Boer, and H. H. De Iongh. 2007. Factors
affecting livestock predation by lions in Cameroon. African Journal of Ecology 45:490–
498.
Van Liere, D., C. Dwyer, D. Jordan, A. Premik-Banič, A. Valenčič, D. Kompan, and N. Siard.
2013. Farm characteristics in Slovene wolf habitat related to attacks on sheep. Applied
Animal Behaviour Science 144:46–56.
Wang, S. W., and D. W. Macdonald. 2006. Livestock predation by carnivores in Jigme Singye
Wangchuck National Park, Bhutan. Biological Conservation 129:558–565.
Wilson, S. M., M. J. Madel, D. J. Mattson, J. M. Graham, J. A. Burchfield, and J. M. Belsky.
2005. Natural landscape features, human-related attractants, and conflict hotspots: a
spatial analysis of human–grizzly bear conflicts. Ursus 16:117–129.
Woodroffe, R., L. G. Frank, P. A. Lindsey, M. K. Symon, S. M. K. ole Ranah, and S. Romañach.
2006. Livestock husbandry as a tool for carnivore conservation in Africa’s community
rangelands: a case–control study. Biodiversity and Conservation 16:1245–1260.
Woodroffe, R., P. A. Lindsey, S. Romañach, A. Stein, and S. M. K. ole Ranah. 2005. Livestock
predation by endangered African wild dogs (Lycaon pictus) in northern Kenya.
Biological Conservation 124:225–234.
Zarco-González, M. M., O. Monroy-Vilchis, and J. Alaníz. 2013. Spatial model of livestock
predation by jaguar and puma in Mexico: conservation planning. Biological Conservation
159:80–87.
Associate Editor: Messmer.
ARTICLE SUMMARY FOR TABLE OF CONTENTS We compared 66 studies that
measured the effectiveness of lethal and nonlethal techniques for reducing large carnivore attacks
on livestock. Preventive husbandry and deterrents demonstrated the greatest effectiveness but
widest variability while lethal removal showed moderate effectiveness with the lowest variation;
however, more studies with consistent metrics of effectiveness are needed to overcome
publication biases toward Canids in the United States, Europe, and Africa and studies reporting
positive effects.
15 | Miller et al.
Figure 1. Assessment of the effectiveness of A) general techniques and B) specific tools for
reducing large carnivore depredation on domestic livestock based on literature review conducted
in 2015 with 66 peer-reviewed papers (published 1980–2014). Effectiveness was calculated as
the percent magnitude of change after a tool was implemented. Positive effectiveness values
More depredation Less depredation
No change after implementation
n = 2 n = 7 n = 4 n = 1 n = 1 n = 2 n = 3 n = 3 n = 5 n = 2 n = 2 n = 1 n = 1 n = 5 n = 1
A
No change after implementation
n = 14 n = 14 n = 6
Multiple carnivores
Black-backed jackal,
caracal, leopard
Brown bear, gray wolf
Brown bear, gray wolf,
Eurasian lynx
Spotted hyena, lion
Ursid
American black bear
Asiatic black bear
Brown bear
Polar bear
Felid
Cheetah
Eurasian lynx
Leopard
Lion
Puma
Tiger
Canid
Dingo
Gray wolf
B
More depredation Less depredation
Preventative husbandry Deterrent Removal
Carnivore species
16 | Miller et al.
indicate decreasing livestock depredation; negative values indicate increasing livestock
depredation. ‘n’ represents the number of studies for each technique or tool; data points indicate
the values provided by studies (some studies reported multiple values, such as from different
sites or species). Data are summarized as boxplots, where boxes indicate the lower, median, and
upper quartiles; vertical lines represent the sample minimum and maximum. Original data are
overlaid on boxplots, where symbol shape represents the carnivore family and symbol color
represents species (see legend).
17 | Miller et al.
Figure 2. Assessment of the effectiveness of carnivore deterrents in reducing livestock
depredation compared with the time duration of effectiveness based on literature review
conducted in 2015 with 66 peer-reviewed papers (published 1980–2014). Panel A shows the
variation in the amount of time that techniques were effective for different carnivore species.
Data are summarized as boxplots, where boxes indicate the lower, median, and upper quartiles;
horizontal lines represent the sample minimum and maximum. Original data are overlaid on
boxplots, where symbol shape represents the carnivore family and symbol color represents
species (see legend). Panel B displays the overall level of effectiveness versus the amount of
time that tool effects lasted. Lines represent ranges of values on the x- or y-axis. Grayscale colors
and dashing are meant to help distinguish between lines and do not represent species. In both
panels, arrows demarcate techniques that were tested during timed trials, which measured the
acoustics
rubber bullets
0
20
40
60
80
100
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Effectiveness (% change)
Time effective (months)
polar bear
Electrified fladry
Light/ sound
device
Unelectrified fladry
17 18 19 20 21
Chemical repellents
Multiple deterrents
Shock device
Acoustics
Shock collar
Gray wolf
American black bear
Brown bear
Polar bear
Indefinite
I
Indefinite
A
B
18 | Miller et al.
minimum time length of effectiveness. Effectiveness was calculated as the percent change in
depredated animals or carnivore behavior when techniques were implemented, where larger
effectiveness values indicate decreasing depredation. The multiple deterrents treatment included
a combination of pepper spray, 12-gauge rubber buckshot, rubber slugs, cracker shells, human
shouting, and guard dogs.
19 | Miller et al.
TABLES
Table 1. Conflict mitigation techniques and tools used as search keywords for literature review
assessing the effectiveness of methods for reducing livestock depredations by large carnivores,
conducted in 2015 with 66 peer-reviewed papers (published 1980–2014).
Tool
Aversive stimuli
Behavior conditioning
Behavior modification
Disruptive stimuli
Repellent
Buffer zone
Core zone
Grazing areas
Land use conflict
Wild prey
Wild ungulate
Contraception
Lethal control
Population control
Problem animal
Retaliation
Retaliatory killing
Translocation
Barrier
Grazing
Guard animal
Guard dog
Guards
Herd
Herder
Hotspot
Husbandry
Livestock breed
Penning
Sensory deterrent or
repellent
Separation
Shepherd
20 | Miller et al.
Table 2. Results from correlation studies found in literature review assessing the effectiveness of techniques for reducing livestock
depredations by large carnivores, conducted in 2015 with 66 peer-reviewed papers (published 1980–2014). Negative or positive
associations indicate that a factor was negatively or positively statistically correlated with livestock depredation, respectively.
Tool type
Factor
Relationship to carnivore attacks on livestock
Negatively associated (depredation
decreases if factor present or increased)
Positively associated (depredation increases
if factor present or increased)
No effect
Livestock
management
No. or density of livestock
African wild dog10, cheetah10, lion10,
leopard10, puma34, spotted hyena10
African wild dog33, cheetah32, gray wolf 6;
jaguar19, leopard15,32, lion32, puma19, snow
leopard4, spotted hyena16,32
Gray wolf 17,28
Mixed herd composition
Gray wolf 17
Amount of free-grazing
livestock
Jaguar34
Year-round calving
Gray wolf 7
Calving season
Jagur19, puma19
Presence of unmanaged
boneyards
Brown bear31
Presence of beehive
Brown bear31
Grazing
management
Pasture size
Gray wolf 6
Leopard16
Confining livestock at
night
Cheetah22, gray wolf 18, leopard22, lion22,
spotted hyena22
Confining livestock at
night with 5 guard dogs
Gray wolf8
Confining livestock at
night with <5 guard dogs
Gray wolf 8
Presence of pole enclosure
Spotted hyena16
Leopard16
Presence of bush
enclosure
Leopard16
Spotted hyena16
Distance to other
enclosuresdwellings
Spotted hyena16
Gray wolf 18, spotted hyena16
Presence of electric fence
Gray wolf 18
21 | Miller et al.
Guarding
Human guards and guard
animals (combined)
Leopard15, tiger15
Presence or no. of human
guards
Gray wolf 14, lion22,29,32, spotted
hyena22,29
Presence or no. of guard
dogs
Gray wolf 14, leopard32, lion22,29,32,
spotted hyena16,29,32
African wild dog33
Leopard22; spotted
hyena22,32
Presence of firearms
Leopards22, spotted hyena22
Lion22
Land-use
management
Distance to cover
Eurasian lynx25, jaguar3,19, lion10,
puma19, spotted hyena10,22,
Gray wolf 28
Leopard16,22, lion16,22,
spotted hyena16
Amount of vegetation
African wild dog33, brown bear31, puma34,
jaguar34, leopard32, spotted hyena32
Cheetah32, lion32
Distance to protected area
Leopard15, lion10, tiger15, spotted
hyena10
Lion5
Wild prey
management
No. or density of wild
prey
African wild dog32, gray wolf 9,
Eurasian lynx21, lion30, snow leopard4
Eurasian lynx20, 25, snow leopard27
Carnivore
removal
Population control
Brown bear23, dingo1, Eurasian lynx12,
Asiatic black bear13, gray
wolf 11
Problem animal control
Brown bear2, Eurasian lynx24
Brown bear23
Translocation
Lion26
Brown bear23
22 | Miller et al.
1Allen and Sparkes 2001; 2Anderson et al. 2002; 3Azevedo and Murray 2007; 4Bagchi and
Mishra 2006; 5Van Bommel et al. 2007; 6Bradley and Pletscher 2005; 7Breck et al. 2011;
8Espuno et al. 2004; 9Gula 2008; 10Gusset et al. 2009; 11Harper et al. 2008; 12Herfindal et al.
2005; 13Huygens et al. 2004; 14Iliopoulos et al. 2009; 15Karanth et al. 2013; 16Kolowski and
Holecamp 2006; 17van Liere et al. 2013; 18Mech et al. 2000; 19Michalski et al. 2006; 20Odden et
al. 2008; 21Odden et al. 2013; 22Ogada et al. 2003; 23Sagor et al. 1997; 24Stahl et al. 2001; 25Stahl
et al. 2002; 26Stander 1990; 27Suryawanshi et al. 2013; 28Treves et al. 2011; 29Tumenta et al.
2013; 30Valeix et al. 2012; 31Wilson et al. 2005; 32Woodroffe et al. 2005; 33Woodroffe et al.
2006; 34Zarco-González et al. 2013.
1
Supporting Information
Table S1. Large carnivore species with body mass >15 kg included in literature review assessing
the effectiveness of techniques for reducing livestock depredations by large carnivores,
conducted in 2015 with 66 peer-reviewed papers (published 1980–2014).
Family
Scientific name
Common name
Canidae
Canis lupus
Gray wolf
Canis rufus
Red wolf
Chrysocyon brachyurus
Maned wolf
Lycaon pictus
African wild dog
Cuon alpinus
Dhole
Canis lupus dingo
Dingo
Canis simensis
Ethiopian wolf
Felidae
Panthera tigris
Tiger
Panthera leo
Lion
Panthera onca
Jaguar
Acinonyx jubatus
Cheetah
Panthera pardus
Leopard
Puma concolor
Puma
Uncia uncia
Snow leopard
Neofelis nebulosa
Clouded leopard
Neofelis diardi
Sunda clouded leopard
Lynx lynx
Eurasian lynx
Hyaenidae
Crocuta crocuta
Spotted hyena
Hyaena brunnea
Brown hyena
Hyaena hyaena
Striped hyena
Ursidae
Ursus maritimus
Polar bear
Ursus arctos
Brown bear
Ursus americanus
American black bear
Tremarctos ornatus
Andean bear
Ursus thibetanus
Asiatic black bear
Melursus ursinus
Sloth bear
Helarctos malayanus
Sun bear
2
Table S2. Data and original units used in Fig. 2A and 2B on technique effectiveness from articles in literature review assessing the
methods for reducing livestock depredations by large carnivores, conducted in 2015 with 66 peer-reviewed papers (published 1980–
2014).
Technique
Tool
Carnivore
species
Units for measuring change
Before
tool use
After
tool use
Effectiveness
(% change)a
Time
effective
Sourceb
Preventive
husbandry
Electric fence
Asiatic black
bear
No. of bears raiding fenced field
NA
100
100
NA
Huygens and
Hayashi 1999
Electric fence
Gray wolf
No. of attacks/year
6.6
0
100
NA
Salvatori and
Mertens 2012
Electric fence
Gray wolf
Frequency of attacks
NA
NA
98
NA
Salvatori and
Mertens 2012
Electric fence
Gray wolf
No. of livestock lost
NA
NA
58
NA
Salvatori and
Mertens 2012
Non-electric
fence
American black
bear
Percent ewes and lambs depredated
1.15
0.25
78
NA
Andelt and
Hopper 2000
Non-electric
fence
Gray wolf
No. of attacks
304
106
65
NA
Ciucci and
Boitani 1998
Non-electric
fence
Puma
Percent ewes and lambs depredated
1.08
0.53
51
NA
Andelt and
Hopper 2000
Guard dog
American black
bear
Percent livestock lost
1.2
0.4
67
NA
Andelt and
Hopper 2000
Guard dog
Brown bear
Percent decrease in depredation
compared to control
NA
3
3
NA
Hansen and
Smith 1999
Guard dog
Cheetah
Percent farms with livestock losses
82
35
47
NA
Marker et al
2005
Guard dog
Dingo
No. farms with livestock losses
93
19
80
NA
Van Bommel
3
Technique
Tool
Carnivore
species
Units for measuring change
Before
tool use
After
tool use
Effectiveness
(% change)a
Time
effective
Sourceb
and Johnson
2012
Guard dog
Eurasian lynx
Proportion of farms with depredation
0.13
0
100
NA
Otstavel et al
2009
Guard dog
Gray wolf
Wolf visits to pasture/day
0.05
0.013
72
NA
Gehring et al.
2010
Guard dog
Brown bear,
gray wolf
Average livestock killed/year
11
6
42
NA
Salvatori and
Mertens 2012
Guard dog
Brown bear,
gray wolf
Average livestock killed/year
15
5
65
NA
Salvatori and
Mertens 2012
Guard dog
Brown bear,
gray wolf,
Eurasian lynx
Proportion of farms with depredation
0.25
0
100
NA
Otstavel et al
2009
Guard dog
Puma
Percent livestock losses
0.8
0.1
88
NA
Andelt and
Hopper 2000
Human guard
Spotted hyena,
lion
No. of livestock lost
60
18
70
NA
Bauer et al
2010
Night
enclosure
Gray wolf
Percent of farms attacked
61
29
52
NA
Van Liere et al.
2013
Night
enclosure
Brown bear,
gray wolf
Average no. of livestock lost
3.6
0.4
89
NA
Rigg et al. 2011
Night
enclosure
Lion
Average no. of livestock lost
2
1
50
NA
Tumenta et al.
2013
Night
enclosure
Puma
Percent of ranches attacked
100
50
50
NA
Mazzolli et al
2002
4
Technique
Tool
Carnivore
species
Units for measuring change
Before
tool use
After
tool use
Effectiveness
(% change)a
Time
effective
Sourceb
Carnivore
removal
Lethal
population
control
Black-backed
jackal, caracal,
leopard
Percent of stock depredated
13.6
4.4
68
NA
McManus et al.
2014
Translocation
American black
bear
No. of bears involved in nuisance
event
123
37
70
NA
Landriault et al.
2009
Translocation
Gray wolf
No. of wolves preying on livestock
63
19
70
NA
Bradley et al.
2005
Translocation
Leopard
No. of attacks on livestock
NA
NA
56
NA
Athreya et al.
2010
Translocation
Lion
No. of lions preying on livestock
18
3
83
NA
Stander 1990
Translocation
Tiger
No. of tigers preying on livestock
3
1
67
NA
Goodrich and
Miquelle 2005
Deterrentb
Acoustics
Dingo
No. dingos consuming bait after
treatment
60
57
5
NA
Edgar et al.
2006
Chemical
repellents
American black
bear
No. of bears remaining in area after
spraying
30
16
47
1 day
Herrero and
Higgins 1998
Chemical
repellents
Brown bear
No. of bears remaining in area after
spraying
36
4
89
1 day
Herrero and
Higgins 1998
Electrified
fladry
Gray wolf
No. of days wolves inside control
versus treatment (fladry) pastures
2
0
100
1–14
days
Lance et al.
2010
Frightening
(light/sound)
device
Gray wolf
No. of calves killed in pastures with or
without devices
16
0
100
3060
days
Breck et al.
2002
Frightening
(light or
Gray wolf
Proportion food consumed by control
versus shock treated wolves
0.84
0.18
79
NA
Shivik et al.
2003
5
Technique
Tool
Carnivore
species
Units for measuring change
Before
tool use
After
tool use
Effectiveness
(% change)a
Time
effective
Sourceb
sound) device
Multiple
deterrents
American black
bear
No. of bears returning to area
62
57
8
1–641
days
Beckmann et al.
2004
Rubber
bullets
American black
bear
Return time after repelling
NA
NA
NA
1–44
days
Leigh 2007
Shock collar
Gray wolf
Mean no. of visits during 40-day
postshock period for control versus
shock treated wolf
17.5
2.2
87
1460
days
Gehring et al.
2006
Shock collar
Gray wolf
Mean no. visits to shock zone before
and after shock treatment (shock
treated animals)
50
19
62
14
days
Hawley et al.
2009
Shock collar
Gray wolf
No. calves killed in year before (1998)
and after (1999) shock collar on alpha
wolf
9
1
89
17
months
Schultz et al.
2005
Shock collar
Gray wolf
Mean no. of visits/day in postshock
period for control vs. shock treated
wolves
1.8
0.2
89
40
days
Rossler et al.
2012
Shock collar
Gray wolf
Proportion food consumed by control
versus shock treated wolves
0.84
0.42
50
NA
Shivik et al.
2003
Shock device
American black
bear
No. of feeders remaining when
protected versus unprotected by shock
device
10
6
40
4.5
months
Breck et al.
2006
Unelectrified
fladry
Gray wolf
No. of wolf approaches that resulted
in crossing fladry
23
0
100
61 days
Musiani et al.
2003
Unelectrified
Gray wolf
Amount of food consumed (kg) by
3.2
2.5
22
NA
Shivik et al.
6
Technique
Tool
Carnivore
species
Units for measuring change
Before
tool use
After
tool use
Effectiveness
(% change)a
Time
effective
Sourceb
fladry
wolves in absence or presence of
fladry
2003
Unelectrified
fladry
Gray wolf
Time with no wolf crossing
NA
NA
NA
90 days
Gehring et al.
2006
Unelectrified
fladry
Gray wolf
No. of times crossing fladry
5
5
0
2 weeks
Lance et al.
2010
‘NA’ indicates that values were not provided by the study. In some cases, effectiveness (magnitude of change) was directly mentioned in the study and did not
need to be calculated.
a Positive values indicate decreasing livestock depredation; negative values indicate increasing livestock depredation. See text for formula and methods.
b Citation details are included in Appendix 1.
7
(A)
0
5
10
15
20
25
Gray wolf
Lion
Brown bear
American black bear
Leopard
Lynx
Puma
Spotted hyena
African wild dog
Dingo
Jaguar
Cheetah
Tiger
Snow leopard
Polar bear
Asiatic black bear
Number of articles
Large carnivore species
(B)
0
5
10
15
20
25
United States
Norway
Kenya
India
France
Cameroon
Australia
Canada
Brazil
Namibia
Botswana
Japan
Italy
Slovakia
Benin
Chad
Guinea
Niger
South Africa
Russia
Croatia
Finland
Greece
Poland
Portugal
Spain
Mexico
Number of articles
Country
Figure S1. Number of articles by (A) large carnivore species and (B) country assessed in
8
literature review on the effectiveness of techniques for reducing livestock depredations by large
carnivores, conducted in 2015 with 66 peer-reviewed papers (published 1980–2014).
9
Appendix 1. Articles included in the literature review assessing the effectiveness of techniques
for reducing livestock depredations by large carnivores, conducted in 2015 with 66 peer-
reviewed papers (published 1980–2014).
Allen, L. R., and E. C. Sparkes. 2001. The effect of dingo control on sheep and beef cattle in
Queensland. Journal of Applied Ecology 38:76–87.
Andelt, W. F., and S. N. Hopper. 2000. Livestock guard dogs reduce predation on domestic
sheep in Colorado. Journal of Range Management 53:259–267.
Anderson, C. R., M. A. Ternent, and D. S. Moody. 2002. Grizzly bear–cattle interactions on two
grazing allotments in northwest Wyoming. Ursus 13:247–256.
Athreya, V. R., M. Odden, J. D. C. Linnell, and K. U. Karanth. 2010. Translocation as a tool for
mitigating conflict with leopards in human-dominated landscapes of India. Conservation
Biology 25:133–141.
Azevedo, F. C. C. De, and D. L. Murray. 2007. Evaluation of potential factors predisposing
livestock to predation by jaguars. Journal of Wildlife Management 71:2379–2386.
Bagchi, S., and C. Mishra. 2006. Living with large carnivores: predation on livestock by the
snow leopard (Uncia uncia). Journal of Zoology 268:217–224.
Bauer, H., H. De Iongh, and E. Sogbohossou. 2010. Assessment and mitigation of human–lion
conflict in West and Central Africa. Mammalia 74:363–367.
Beckmann, J. P., C. W. Lackey, and J. Berger. 2004. Evaluation of deterrent techniques and dogs
to alter behavior of “nuisance” black bears. Wildlife Society Bulletin 32:1141–1146.
Bradley, E. H., D. H. Pletscher, E. E. Bangs, K. E. Kunkel, D. W. Smith, C. M. Mack, T. J.
Meier, J. A. Fontaine, C. C. Niemeyer, and M. D. Jimenez. 2005. Evaluating wolf
translocation as a nonlethal method to reduce livestock conflicts in the northwestern
United States. Conservation Biology 19:1498–1508.
Bradley, E. H., and D. H. Pletscher. 2005. Assessing factors related to wolf depredation of cattle
in fenced pastures in Montana and Idaho. Wildlife Society Bulletin 33:1256–1265.
Breck, S. W., B. M. Kluever, M. Panasci, J. Oakleaf, T. Johnson, W. Ballard, L. D. Howery, and
D. L. Bergman. 2011. Domestic calf mortality and producer detection rates in the
Mexican wolf recovery area: implications for livestock management and carnivore
compensation schemes. Biological Conservation 144:930–936.
Breck S. W., N. J. Lance, and P. Callahan. 2006. A shocking device for protection of
10
concentrated food sources from black bears. Wildlife Society Bulletin 34:23–26.
Breck, S. W., Williamson, R., C. Niemeyer, and J. A. Shivik. 2002. Non-lethal radio activated
guard for deterring wolf depredation in Idaho: summary and call for research.
Proceedings of the 20th Vertebrate Pest Conference 223–226.
Ciucci, P., and L. Boitani. 1998. Wolf and dog depredation on livestock in central Italy. Wildlife
Society Bulletin 26:504–514.
Edgar, J. P., R. G. Appleby, and D. N. Jones. 2006. Efficacy of an ultrasonic device as a
deterrent to dingoes (Canis lupus dingo): a preliminary investigation. Journal of Ethology
25:209–213.
Espuno, N., B. Lequette, M.-L. L. Poulle, P. Migot, and J.-D. Lebreton. 2004. Heterogeneous
response to preventive sheep husbandry during wolf recolonization of the French Alps.
Wildlife Society Bulletin 32:1195–1208.
Gehring, T. M., J. E. Hawley, S. J. Davidson, S. T. Rossler, A. C. Cellar, R. N. Schultz, A. P.
Wydeven, and K. C. VerCauteren. 2006. Are viable non-lethal management tools
available for reducing wolf–human conflict? Preliminary results from field experiments.
Pages 2–6 in R. M. Timm and J. M. O’Brien, editors. Proceedings of the 22nd Vertebrate
Pest Conference. University of California, Davis, USA.
Gehring, T. M., K. C. VerCauteren, M. L. Provost, and A. C. Cellar. 2010. Utility of livestock-
protection dogs for deterring wildlife from cattle farms. Wildlife Research 37:715.
Goodrich, J. M., and D. G. Miquelle. 2005. Translocation of problem Amur tigers Panthera
tigris altaica to alleviate tiger–human conflicts. Oryx 39:454–457.
Gula, R. 2008. Wolf depredation on domestic animals in the Polish Carpathian Mountains.
Journal of Wildlife Management 283–289.
Gusset, M., M. J. Swarner, L. Mponwane, K. Keletile, and J. W. McNutt. 2009. Human–wildlife
conflict in northern Botswana: livestock predation by endangered African wild dog. Oryx
43:67–72.
Hansen, I., and M. E. Smith. 1999. Livestock-guarding dogs in Norway Part II: different working
regimes. Journal of Range Management 52:312–316.
Harper, E., W. J. Paul, L. D. Mech, and S. Weisberg. 2008. Effectiveness of lethal, directed
wolf-depredation control in Minnesota. Journal of Wildlife Management 72:778–784.
Hawley, J. E., T. M. Gehring, R. N. Schultz, S. T. Rossler, and A. P. Wydeven. 2009.
11
Assessment of shock collars as nonlethal management for wolves in Wisconsin. Journal
of Wildlife Management 73:518–525.
Herfindal, I., J. D. C. Linnell, P. F. Å. L. F. Moa, J. Odden, L. B. Austmo, and R. Andersen.
2005. Does recreational hunting of lynx reduce depredation losses of domestic sheep?
Journal of Wildlife Management 69:1034–1042.
Herrero, S., and A. Higgins. 1998. Field use of capsicum spray as a bear deterrent. Ursus
10:533–537.
Huygens, O. C., and H. Hayashi. 1999. Using electric bear fences to reduce Asiatic black
depredation in Nagano prefecture, central Japan. Wildlife Society Bulletin 27:959–964.
Huygens, O. C., F. T. van Manen, D. A. Martorello, H. Hayashi, and J. Ishida. 2004.
Relationships between Asiatic black bear kills and depredation costs in Nagano
Prefecture, Japan. Ursus 15:197–202.
Iliopoulos, Y., S. Sgardelis, V. Koutis, and D. Savaris. 2009. Wolf depredation on livestock in
central Greece. 54:11–22.
Karanth, K. K., A. M. Gopalaswamy, P. K. Prasad, and S. Dasgupta. 2013. Patterns of human–
wildlife conflicts and compensation: insights from Western Ghats protected areas.
Biological Conservation 166:175–185.
Kolowski, J., and K. E. K. Holekamp. 2006. Spatial, temporal, and physical characteristics of
livestock depredations by large carnivores along a Kenyan reserve border. Biological
Conservation 128:529–541.
Lance, N. J., S. W. Breck, C. Sime, P. Callahan, and J. A. Shivik. 2010. Biological, technical,
and social aspects of applying electrified fladry for livestock protection from wolves
(Canis lupus). Wildlife Research 37:708–714.
Landriault, L. J., G. S. Brown, J. Hamr, and F. F. Mallory. 2009. Age, sex and relocation
distance as predictors of return for relocated nuisance black bears Ursus americanus in
Ontario, Canada. Wildlife Biology 15:155–164.
Leigh, J. 2007. Effects of aversive conditioning on behavior of nuisance Louisiana black bears.
Thesis, Louisiana State University, Baton Rouge, USA.
Marker, L. L., A. J. Dickman, and D. W. Macdonald. 2005. Survivorship and causes of mortality
for livestock-guarding dogs on Namibian Rangeland. Rangeland Ecology & Management
58:337–343.
12
Mazzolli, M., M. E. Graipel, and N. Dunstone. 2002. Mountain lion depredation in southern
Brazil. 105:43–51.
McManus, J. S., A. J. Dickman, D. Gaynor, B. H. Smuts, and D. W. Macdonald. 2014. Dead or
alive? Comparing costs and benefits of lethal and non-lethal human–wildlife conflict
mitigation on livestock farms. Oryx 49:687–695.
Mech, L. D., E. K. Harper, T. J. Meier, and W. J. Paul. 2000. Assessing factors that may
predispose Minnesota farms to wolf depredations on cattle. Wildlife Society Bulletin
28:623–629.
Michalski, F., R. L. P. Boulhosa, A. Faria, and C. A. Peres. 2006. Human–wildlife conflicts in a
fragmented Amazonian forest landscape: determinants of large felid depredation on
livestock. Animal Conservation 9:179–188.
Miller, G. D. 1987. Field tests of potential polar bear repellents. International Conference on
Bear Restoration and Management 7:383–390.
Musiani, M., C. Mamo, L. Boitani, C. Callaghan, and C. C. Gates. 2003. Wolf depredation trends
and the use of fladry barriers to protect livestock in western North America. Conservation
Biology 17:1538–1547.
Odden, J., I. Herfindal, J. D. C. Linnell, and R. Andersen. 2008. Vulernability of domestic sheep
to lynx depredation in relation to roe deer density. Journal of Wildlife Management
72:276–282.
Odden, J., E. B. Nilsen, and J. D. C. Linnell. 2013. Density of wild prey modulates lynx kill rates
on free-ranging domestic sheep. PloS One 8:e79261.
Ogada, M. O., R. Woodroffe, N. O. Oguge, and L. G. Frank. 2003. Limiting depredation by
African carnivores: the role of livestock husbandry. Conservation Biology 17:1521–1530.
Otstavel, T., K. A. Vuori, D. E. David, A. Valros, O. Vainio, and H. Saloniemi. 2009. The first
experience of livestock guarding dogs preventing large carnivore damages in Finland.
Estonian Journal of Ecology 58:216.
Rigg, R., S. Finďo, M. Wechselberger, M. L. Gorman, C. Sillero-Zubiri, and D. W. Macdonald.
2011. Mitigating carnivore–livestock conflict in Europe: lessons from Slovakia. Oryx
45:272–280.
Rossler, S. T., T. M. Gehring, R. N. Schultz, M. T. Rossler, A. P. Wydeven, and J. E. Hawley.
2012. Shock collars as a site-aversive conditioning tool for wolves. Wildlife Society
13
Bulletin 36:176–184.
Sagor, J. T., J. E. Swenson, and E. Roskaft. 1997. Compatibility of brown bear Ursus arctos and
free-ranging sheep in Norway. Biological Conservation 81:91–95.
Salvatori, V., and A. D. Mertens. 2012. Damage prevention methods in Europe: experiences
from LIFE nature projects. Hystrix 23:73–79.
Schultz, R., K. W. Jonas, L. H. Skuldt, and A. P. Wydeven. 2005. Experimental use of dog-
training shock collars to deter depredation by gray wolves. Wildlife Society Bulletin
33:142–148.
Shivik, J. A., A. Treves, and P. Callahan. 2003. Nonlethal techniques for managing predation:
primary and secondary repellents. Conservation Biology 17:1531–1537.
Stahl, P., J. M. Vandel, V. Herrenschmidt, and P. Migot. 2001. The effect of removing lynx in
reducing attacks on sheep in the French Jura Mountains. Biological Conservation
101:15–22.
Stahl, P., J. M. Vandel, S. Ruette, L. Coat, Y. Coat, and L. Balestra. 2002. Factors affecting lynx
predation on sheep in the French Jura. Journal of Applied Ecology 39:204–216.
Stander, P. E. 1990. A suggested management strategy for stock-raiding lions in Namibia. South
African Journal of Wildlife Research 20:37–43.
Suryawanshi, K. R., Y. V. Bhatnagar, S. Redpath, and C. Mishra. 2013. People, predators and
perceptions: patterns of livestock depredation by snow leopards and wolves. Journal of
Applied Ecology 50:550–560.
Treves, A., K. a. Martin, A. P. Wydeven, and J. E. Wiedenhoeft. 2011. Forecasting
environmental hazards and the application of risk maps to predator attacks on livestock.
BioScience 61:451–458.
Tumenta, P. N., H. H. de Iongh, P. J. Funston, and H. A. Udo de Haes. 2013. Livestock
depredation and mitigation methods practised by resident and nomadic pastoralists
around Waza National Park, Cameroon. Oryx 47:237–242.
Valeix, M., G. Hemson, A. J. Loveridge, G. Mills, and D. W. Macdonald. 2012. Behavioural
adjustments of a large carnivore to access secondary prey in a human-dominated
landscape. Journal of Applied Ecology 49:73–81.
Van Bommel, L., M. D. Bij de Vaate, W. F. De Boer, and H. H. De Iongh. 2007. Factors
affecting livestock predation by lions in Cameroon. African Journal of Ecology 45:490–
14
498.
Van Bommel, L., and C. N. Johnson. 2012. Good dog! Using livestock guardian dogs to protect
livestock from predators in Australia’s extensive grazing systems. Wildlife Research
39:220.
Van Liere, D., C. Dwyer, D. Jordan, A. Premik-Banič, A. Valenčič, D. Kompan, and N. Siard.
2013. Farm characteristics in Slovene wolf habitat related to attacks on sheep. Applied
Animal Behaviour Science 144:46–56.
Wilson, S. M., M. J. Madel, D. J. Mattson, J. M. Graham, J. A. Burchfield, and J. M. Belsky.
2005. Natural landscape features, human-related attractants, and conflict hotspots: a
spatial analysis of human–grizzly bear conflicts. Ursus 16:117–129.
Woodroffe, R., Æ. L. G. Frank, P. A. Lindsey, Æ. M. K. Symon, L. G. Frank, P. A. Lindsey, S.
M. K. ole Ranah, and S. Romañach. 2006. Livestock husbandry as a tool for carnivore
conservation in Africa’s community rangelands: a case–control study. Biodiversity and
Conservation 16:1245–1260.
Woodroffe, R., P. A. Lindsey, S. Romañach, A. Stein, and S. M. K. ole Ranah. 2005. Livestock
predation by endangered African wild dogs (Lycaon pictus) in northern Kenya.
Biological Conservation 124:225–234.
Wooldridge, D. 1980. Polar bear electronic deterrent and detection systems. Bears: Their
Biology and Management 5:264–269.
Zarco-González, M. M., O. Monroy-Vilchis, and J. Alaníz. 2013. Spatial model of livestock
predation by jaguar and puma in Mexico: conservation planning. Biological Conservation
159:80–87.
... Our results must be interpreted with caution because, as mentioned, we were not able to control for important variables that are known to influence livestock depredation (including predator and prey abundances) or reporting bias. Despite the limitations of this study, our findings are consistent with the global reviews indicating the relative efficacy of non-lethal vs. lethal predator management (van Eeden et al. 2018;Treves et al. 2016;Eklund et al. 2017;Miller et al. 2016). ...
... Several research questions arise out of this and similar work. Given the high variability in the efficacy of most livestock and predation management techniques in reducing livestock predation (Miller et al. 2016), the applicability, efficacy and cost-effectiveness of any management technique appears to be context dependent. Ideally, several studies across multiple contexts (livestock types, breeds and ages, socio-economic and cultural status of the farming community, environmental conditions, grazing pattern, dominant predator, geographic region, etc.) are required to ascertain the usefulness of shepherding in reducing livestock predation (Miller et al. 2016). ...
... Given the high variability in the efficacy of most livestock and predation management techniques in reducing livestock predation (Miller et al. 2016), the applicability, efficacy and cost-effectiveness of any management technique appears to be context dependent. Ideally, several studies across multiple contexts (livestock types, breeds and ages, socio-economic and cultural status of the farming community, environmental conditions, grazing pattern, dominant predator, geographic region, etc.) are required to ascertain the usefulness of shepherding in reducing livestock predation (Miller et al. 2016). For example, the Before-After-Control-Impact (BACI) approach, considered a 'gold standard' (Treves et al. 2016) could consider predation alongside other causes of stock loss and mortality and would compare them under different predator management approaches across multiple environments. ...
Article
Predation threatens the viability of livestock farming, while lethal predator management can negatively influence wildlife ecology. There is renewed interest in non-lethal vs lethal methods of livestock protection, but a systematic comparison is lacking. Using multivariate models, we explored how predator management (shepherd, no shepherd), land tenure, flock characteristics, and environmental factors drive losses of small livestock across the Northern Cape, South Africa. Black-backed jackal and caracal were the dominant livestock predators in both management groups. Predation of small livestock was five-fold lower in the shepherd (1.29% ± 0.38) compared to the non-shepherd group (6.09% ± 0.51; p < 0.0001), with a seven-fold lower-level of lamb predation (1.67% ± 0.51 vs. 11.52% ± 0.99; p < 0.0001). Predator management, livestock type, and flock size (but not land tenure or environmental factors) were predictor variables in a best-fit linear mixed effects model describing small livestock losses (p < 0.0001). We interpret our findings with caution because we could not control for predator and prey abundances, and the non-herder group could have inflated their predation estimates. While the efficacy of shepherding requires more research, we suggest that it is a viable predation management approach in South Africa and beyond.
... Several studies have evaluated their behavior and effectiveness after integration into the herd ( Coppinger et al. 1988 ;Andelt 1992 ;Espuno et al. 2004 ;Gehring et al. 2010b ;Rigg et al. 2011 ;van Bommel and Johnson 2012 ;Marker et al. 2021 ;Lieb et al. 2021 ). Of these, most studies support their efficacy in reducing losses caused by various predators, both solitary ( Woodroffe et al. 2007 ;Marker et al. 2021 ) and social predator species ( van Bommel and Johnson 2012 ;Lieb et al. 2021 ), to livestock, although the values may vary ( Miller et al. 2016 ). Bruns et al. (2020) , on the basis of a review of 30 studies (7 focused on LGDs), found they had the highest variation in effectiveness when compared with other measures (calving control, deterrents, fencing, herding, lethal control, mixed measures, and translocation), ranging from an increase of depredation by 23.3% to a decrease by 100%. ...
... Bruns et al. (2020) , on the basis of a review of 30 studies (7 focused on LGDs), found they had the highest variation in effectiveness when compared with other measures (calving control, deterrents, fencing, herding, lethal control, mixed measures, and translocation), ranging from an increase of depredation by 23.3% to a decrease by 100%. However, in another review, LGDs were found to reduce depredation damage from 3% to 100% (seven studies), and their effectiveness varied across carnivore species ( Miller et al. 2016 ). More recent studies also provide strong evidence of LGDs reducing the depredation of cattle by cheetah (Acinonyx jubatus) in Namibia ( Marker et al. 2021 ), sheep by wolves in Idaho ( Stone et al. 2017 ), and cattle by leopard (Panthera pardus) in South Africa ( McManus et al. 2015 ). ...
Article
Full-text available
The efficacy of livestock guarding dogs (LGDs; Canis familiaris) on modern ranches in the dense multiuse landscape of rural northern Israel is controversial. Minimal time is spent by the ranchers with the herd and LGDs, and the LGDs are known to wander to nearby army bases, homesteads, villages, and other facilities. Thirteen Akbash and six mixed-breed LGDs guarding cattle in a paddock were observed through direct observations and tracking with Global Positioning System collars. Predator presence and interaction with LGDs were recorded using telemetry and trail cameras. In addition, 10 local ranchers were interviewed to assess the effects of management and LGD use on depredation. We expected Akbash LGDs to exhibit behavioral traits consistent with depredation mitigation and that differing ranch-LGD management methods would impact depredation levels. At the study ranch, depredations were at a minimum despite the presence of three wolf packs (Canis lupus) and jackals (Canis aureus) in the vicinity of the observed ranch. The Akbash LGDs spatially displaced wolves and temporally displaced jackals, but they also regularly roamed away from the paddock and returned. In addition, Akbash LGDs were more likely to follow the herd than mixed-breed LGDs; the total number of LGDs in the paddock increased with the number of newborn calves; and LGD intra-aggression increased with the number of LGDs present in the paddock. In the survey, we found little relationship between ranch management type and depredation outcomes. In particular, the use of protective enclosures by some ranches did not mitigate depredation compared with ranches without enclosures. In modern multiuse landscapes, Akbash LGDs show potential for being an important component of depredation mitigation, but their relative contribution needs to be studied further. In addition, the use of protective enclosures, which are known to have negative ecological impacts, should be reconsidered. Several improvements to LGD management are suggested.
... We found no significant effect of whether poultry was fenced on reports of persisting predator issues, although we did not specify the type of fencing or asked if it was likely to be predator proof. Reviews indicate that electrified fencing has strongest and most persisting effect as a predator deterrent (Miller et al., 2016;Moreira-Arce et al., 2018;Khorozyan and Waltert, 2019), while the efficacy of LGDs, which has the largest overall effect as a predator deterrent (Van Eeden et al., 2018a), sometimes shows ambiguous results (Miller et al., 2016;Khorozyan and Waltert, 2019). The combination of LGDs with fencing to reduce the area over A c c e p t e d M a n u s c r i p t which birds move is likely to be the most successful combination. ...
... We found no significant effect of whether poultry was fenced on reports of persisting predator issues, although we did not specify the type of fencing or asked if it was likely to be predator proof. Reviews indicate that electrified fencing has strongest and most persisting effect as a predator deterrent (Miller et al., 2016;Moreira-Arce et al., 2018;Khorozyan and Waltert, 2019), while the efficacy of LGDs, which has the largest overall effect as a predator deterrent (Van Eeden et al., 2018a), sometimes shows ambiguous results (Miller et al., 2016;Khorozyan and Waltert, 2019). The combination of LGDs with fencing to reduce the area over A c c e p t e d M a n u s c r i p t which birds move is likely to be the most successful combination. ...
Article
Full-text available
Growth in the free-range and pastured egg industries has increased globally, necessitating improvements in predator control. Some egg producers are turning to the use of livestock guardian dogs (LGD; Canis familiaris) to protect hens from predation. We worked on a property where pastured layer hens were protected by two Maremma LGD that were released from their chicken enclosure for 2–3 nights a week. GPS tracking showed that the dogs were more strongly bonded to people than the chickens, spending most of their time at night (96.1% of location data) close to the farmhouse and only 0.09% near their chicken paddock. Despite this lack of attendance, we found no change in the paddock space use by chickens with or without the dogs present (p=0.999). Furthermore, camera trapping revealed 40 red fox (Vulpes vulpes) events over the 46-day monitoring period, with less fox activity on nights when the LGDs were allowed to roam the property and motion-activated spotlights were also deployed (P=0.048). An online survey of 59 poultry producers found strong belief in the effectiveness of LGDs, although half the respondents (52%) indicated that they were still experiencing predation issues. There was no association with the reported degree of human bonding of their LGDs, but respondents were more likely to report current issues with predators if they owned 100 or more chickens (P=0.031). The present case study as well as the farmer survey have identified that LGDs can be strongly bonded to people. Although there was no evidence of subsequently increased risk of predation, bonding with people could draw LGDs away from the animals they should be defending, with predation risk for poultry likely to depend on how far away LGDs move from their livestock.
... Ridurre i danni alle attività zootecniche a livelli economicamente e socialmente tollerabili rappresenta quindi una priorità al fine di favorire da un lato il mantenimento e lo sviluppo delle attività economiche tradizionali, dall'altro la conservazione a lungo termine del lupo. Le strategie di mitigazione dei danni che la letteratura scientifica evidenzia come più efficaci, in particolare per il lupo, si possono riassumere in un cambio importante nella gestione del bestiame, con una maggiore attenzione e un maggior investimento in misure tra cui la stabulazione notturna del bestiame, la presenza di uno o più pastori, di cani da guardiania e di recinzioni adeguate (Linell et al. 1996;Miller et al. 2016;Treves, Krofel e McManus 2016;Van Eeden, Eklund et al. 2018;Van Eeden, Crowther et al. 2018;Eklund et al. 2017;Lorand et al. 2022). In generale la combinazione di diverse strategieè raccomandata per un maggiore successo, e l'efficacia delle diverse strategie dipende fortemente dal contesto locale (Van Eeden, Eklund et al. 2018). ...
... When human-carnivore conflict occurs, one management option is to remove individual carnivores (i.e. management removal) involved in conflict (Blejwas et al., 2002;Miller et al., 2016;Moreira-Arce et al., 2018). However, several studies have found that when management removals are used excessively, there can be negative demographic outcomes for carnivores (Quevedo et al., 2018;Woodroffe & Frank, 2005), indicating that the impact of management removal relative to other mortality factors needs to be better understood for recovering carnivore populations. ...
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Recovering and maintaining large carnivore populations is a global conservation challenge that requires better knowledge of the factors affecting their populations, particularly in shared landscapes (i.e. non‐protected areas where people occupy and or utilize the land). The Mexican wolf ( Canis lupus baileyi ) is an endangered wolf subspecies being recovered on shared landscapes in the Southwest United States and Mexico. We used data from the U.S. program to model population growth, evaluate the impact of management removal and illegal killing relative to other demographic factors, and test hypotheses about factors influencing rates of management removal and illegal killing. From 1998 to 2019, the population growth averaged 12% per year. Rates of natural reproduction, illegal killing and other mortality remained consistent over the 22 years; while releases, translocations and management removals varied markedly between two time periods, phase 1:1998–2007 and phase 2:2008–2019. The number of wolves removed for conflict management was higher during phase 1 (average ~ 13 per year, rate = 24.8%) than phase 2 (average of ~5 per year, rate = 5.2%). This decrease in management removal resulted in the wolf population resuming growth after a period of population stagnation. Two factors influenced this decrease, a change in policy regarding removal of wolves (stronger modelling support) and a decrease in the number of captive‐reared adult wolves released into the wild (weaker modelling support). Illegal mortality was relatively constant across both phases, but after the decrease in management removal, illegal mortality became the most important factor (relative importance shifted from 28.2% to 50.1%). Illegal mortality was positively correlated with rates of reintroduction and translocation of wolves and negatively correlated with the rate of management removal. Synthesis and applications . Using management removal to reduce human–carnivore conflict can have negative population impacts if not used judiciously. Recovering and maintaining carnivore populations in shared landscapes may require greater tolerance of conflict and more emphasis on effective conflict prevention strategies and compensation programs for affected stakeholders.
... toxic baits or poisons, traps, hunting) and nonlethal (e.g. enclosure of livestock, livestock-guard dogs, collars, repellents) methods and vary in their effectiveness (Fernandez-Arhex et al. 2016;Miller et al. 2016;van Eeden et al. 2018). Although being highly variable, responses of authorities and farmers to carnivore predation have evolved from a traditional top-down, command and control approach, for example, through lethal control (Holling and Meffe 1996) to aspirations of co-existence (Dickman et al. 2011;Bergstrom 2017). ...
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Lethal control of native carnivores as a principal management strategy can have unforseen ecological consequences and is often of questionable efficacy. Using as a case study a region where the lethal control of native puma and culpeo foxes has been incentivised via legislation for over 50 years, we examined how this policy has affected institutional narratives in the region. We conducted four key informant interviews with members of relevant institutions to establish their perspectives on carnivore management. We also examined the informational basis for the current legislative approach to predation, and identified topics for discussion surrounding legislation and its formation for decision-makers in the province. We identified a duality where two branches of gove rnment have contradictory policies regarding livestock production and carnivore management. All institutions involved in predation management in rural landscapes produced narratives supporting sustainable development, and suggested, in varying degrees, that alternatives to lethal control would be positive. Interviewees stated that modification of the existing laws require livestock producers to demand a change from policy-makers, who generally view carnivores poorly. Furthermore, there is evidence that discussions surrounding management strategies suffer from cultural bias, with rural inhabitants finding themselves marginalised from the decision-making process. We identified a need for empathy regarding the adverse situation of rural inhabitants facing the impacts of predation, and an appreciation of the role that carnivores play within their environments, so as to change the negative discourse surrounding human–carnivore interactions.
... Many factors may influence wolf depredation risk, such as vegetation type, landscape characteristics, livestock availability, natural prey density, wolf density, and husbandry practices (Miller, 2015;Bruns et al., 2020). Husbandry parameters include herd size and species composition, as well as preventive measures, such as surveillance by shepherds, livestock guardian dogs, night confinement, calving control, presence of young livestock, and quality of fences (reviews by Miller et al., 2016;Eklund et al., 2017;Bruns et al., 2020). However, the relative efficacy of each of these preventive measures for each livestock type in quantitative terms remains unclear. ...
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Open Access for 50 days: https://authors.elsevier.com/a/1h2iJ1R%7EeSm9%7E Abstract Livestock depredation is the primary driver of wolf-human conflict worldwide, threatening wolf conservation and impacting human livelihoods. Most countries implement relevant compensation programs, which are however rarely accompanied by proactive husbandry practices vetted with scientific research. We investigated the influence of husbandry practices on wolf depredation losses for 70 sheep/goat and 68 cattle herds with quantitative modeling of data from semi-structured interviews of livestock farmers along a livestock damage gradient in NW Greece. Sheep/goat herds were better protected than cattle herds in seven preventive measures and annual losses of sheep/goat livestock units were three times lower than losses of cattle livestock units in our study area. Furthermore, according to national compensation data from Greece, costs paid for cattle have doubled in recent years, whereas they have been cut in half for sheep/goats. Our modeling identified three core preventive measures that significantly reduced wolf depredation risk for both herd types, namely increased shepherd surveillance, systematic night confinement, and an adequate number of livestock guardian dogs (optimal ratio was 3 Greek guardian dogs per 100 sheep/goats and 7 guardian dogs per 100 cattle). Keeping young livestock in enclosures and not abandoning livestock carcasses in pastures were additional effective preventive measures for cattle herds. Our study provides evidence to inform the subsidizing policy put forth in the Common Agricultural Policy of the European Union. It can also serve to inform or revise wildlife-livestock conflict mitigation policy in countries challenged with the competing goals of conserving large carnivores while maintaining traditional grazing regimes.
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Long-term records of individual Panthera leo permitted the categorization of stock-raiding lions as habitual "problem animals' or "occasional stock raiders'. Management strategies for each group under varying conditions are presented, with optimal solutions emerging as translocation for occasional stock raiders and elimination for problem animals. -from Author
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We determined cause of death for 182 cattle found dead on 2 adjacent public land grazing allotments in northwest Wyoming during 1994-96. Grizzly bears (Ursus arctos) killed fifty-one calves and 6 adults, representing 1.1% (mean) of the annual calf herd and 0.1% of the annual adult herd. An additional 0.9-1.8% of remaining calves were missing each year. Black bears (U. americanus), although present, were not implicated in cattle depredation. We believe that missing calves experienced depredation similar to discovered calves because the proportion killed by bears was similar for those equipped with mortality-sensing transmitters and unmarked calves (P = 0.73). Thus, estimated depredation equaled 78 calves or 1.3-2.2% of the annual calf herd. All observed depredation occurred at night (n = 9). Kills were separated by a mean of 3 days (n = 50) and occurred between 16 June and 13 September (median = 9 August). Radiotagged grizzly bears (n = 17) spent a greater proportion of time in the study area while depredations were occurring, and 10 were located near cattle more frequently than expected (P < 0.05), but most did not kill cattle. Although individuals from all sex and age (subadult, adult) groups except subadult males killed cattle, 3 adult males were responsible for 90% of confirmed losses. We employed management actions including euthanasia, translocation, and aversive conditioning to remove chronic depredators. No depredations were discovered following absence of the 3 depredating males in 1996, unlike the previous 2 years when losses continued for an additional 4 to 6 weeks. This suggests that removal of chronic depredators can reduce losses. Other bears did not become more depredatory, although many were known to utilize cattle carcasses. Removal of cattle carcasses during 1996 appeared to reduce bear densities but did not deter depredatory bear behavior. Identification and removal of depredatory individuals appears key in addressing conflicts with grizzly bears on range-lands.