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Landscape-scale accessibility of livestock to tigers: Implications of spatial grain for modeling predation risk to mitigate human-carnivore conflict

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Innovative conservation tools are greatly needed to reduce livelihood losses and wildlife declines resulting from human–carnivore conflict. Spatial risk modeling is an emerging method for assessing the spatial patterns of predator–prey interactions, with applications for mitigating carnivore attacks on livestock. Large carnivores that ambush prey attack and kill over small areas, requiring models at fine spatial grains to predict livestock depredation hot spots. To detect the best resolution for predicting where carnivores access livestock, we examined the spatial attributes associated with livestock killed by tigers in Kanha Tiger Reserve, India, using risk models generated at 20, 100, and 200-m spatial grains. We analyzed land-use, human presence, and vegetation structure variables at 138 kill sites and 439 random sites to identify key landscape attributes where livestock were vulnerable to tigers. Land-use and human presence variables contributed strongly to predation risk models, with most variables showing high relative importance (≥0.85) at all spatial grains. The risk of a tiger killing livestock increased near dense forests and near the boundary of the park core zone where human presence is restricted. Risk was nonlinearly related to human infrastructure and open vegetation, with the greatest risk occurring 1.2 km from roads, 1.1 km from villages, and 8.0 km from scrubland. Kill sites were characterized by denser, patchier, and more complex vegetation with lower visibility than random sites. Risk maps revealed high-risk hot spots inside of the core zone boundary and in several patches in the human-dominated buffer zone. Validation against known kills revealed predictive accuracy for only the 20 m model, the resolution best representing the kill stage of hunting for large carnivores that ambush prey, like the tiger. Results demonstrate that risk models developed at fine spatial grains can offer accurate guidance on landscape attributes livestock should avoid to minimize human–carnivore conflict.
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... Spatial modelling of con ict or predictive risk modelling has become one of the major tools to understand human-carnivore con ict (HCC) ( However, most studies employ aspatial models to predict predation risk using spatial correlates (Soh et al. 2013;Miller et al. 2015). Since most ecological variables exhibit a certain degree of spatial autocorrelation, therefore, it is important to account for the spatial nature of the data (Gri th 1992; Legendre 1993), when modelling predation risk by carnivores. ...
... Scale and variable selection: To construct a multiscale model, each of these variables (except human footprint, LULC and FRAGSTATS variable) were resampled at ve scales: 30m (the highest resolution available), 50m (average kill drag distance for tiger, as indicated by literature (Karanth and Sunquist, 2000;Miller et al., 2015)), 100m (midpoint between ne and coarse resolution), 350m (maximum kill drag distance from literature), 1200m (coarsest resolution used by us and at which most global environmental data is available). Thus, in total there were 118 variables. ...
... Tiger is an ambush predator, therefore in areas where there is very low cover, it might be very di cult to make a kill, but in areas where cover is high the chances of success may improve (Greene 1986;Murray et al. 1995;Karanth and Sunquist 2000;Sunquist 2010). Studies done on tiger and other carnivores have also found that livestock predation risk was higher in habitats with high shrub density, because it provides cover for these predators (Davie et al. 2014;Miller et al. 2015). However, if the cover is too dense it is also less likely for grazers like livestock to venture into such patches because they would be devoid of grasses. ...
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Context Spatial modeling of human-carnivore conflict has recently gained traction and predictive maps have become a great tool to understand the distribution of present and future conflict risk. However, very few such studies consider scale and use appropriate spatial modeling tools. Objectives This study aimed at understanding the ecological predictors of human-tiger conflict and predicting livestock predation risk by reintroduced tigers in Panna Tiger Reserve, Central India, by modelling livestock kill as a function of various tiger relevant ecological variables, at multiple scales employing spatially explicit statistical tools. Methods Geostatistical modeling was used to create raster layers of covariates (prey, cover, human activities) following which univariate scaling was done. Livestock loss by tiger was then modelled using geoGAM and spatially explicit conflict risk predicted. Results It was found that prey and shrub cover both selected at fine scale, were key ecological determinants of human-tiger conflict. Prey showed an inverse relationship with livestock predation and shrub non-linear, livestock predation increasing with increase in shrub cover, but decreasing beyond a certain point. Thus, in habitats where optimum ambush cover is available but prey presence is low at fine-scale, carnivores are more likely to depredate domestic livestock since livestock have lost most of their anti-predator behaviours. Conclusions Livestock kill by tiger is a culmination of predator choice and foraging tactics, and, prey vulnerability and defence mechanism. Thus, the spatially explicit predation risk map can provide a basis to guide adequate mitigation measures, as per the risk probability.
... Therefore, large carnivores residing outside the protected areas in highly human-dominated landscapes require effective management for their conservation (Linnell et al., 2001). For instance, snow leopards (Panthera uncia) in the Himalayan region and leopards (Panthera pardus) in India and Pakistan tend to kill more livestock near the human habitation where the livestock is high in number and easily accessible (Dar et al., 2009;Aryal et al., 2014;Miller et al., 2015), whereas tigers (Panthera tigris) generally depredate livestock inside the forest, away from villages and human habitation (Wang and Macdonald, 2006;Miller et al., 2015). However, due to the degraded status of their habitats, wolves (Canis lupus pallipes) in India generally reside outside the protected areas where most of the interactions between wolves and humans occur . ...
... Therefore, large carnivores residing outside the protected areas in highly human-dominated landscapes require effective management for their conservation (Linnell et al., 2001). For instance, snow leopards (Panthera uncia) in the Himalayan region and leopards (Panthera pardus) in India and Pakistan tend to kill more livestock near the human habitation where the livestock is high in number and easily accessible (Dar et al., 2009;Aryal et al., 2014;Miller et al., 2015), whereas tigers (Panthera tigris) generally depredate livestock inside the forest, away from villages and human habitation (Wang and Macdonald, 2006;Miller et al., 2015). However, due to the degraded status of their habitats, wolves (Canis lupus pallipes) in India generally reside outside the protected areas where most of the interactions between wolves and humans occur . ...
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Gray wolves are capable of adapting to human-dominated landscapes by utilizing domestic prey as a source of food. Livestock depredation by wolves incurs a heavy economic loss to the villagers, resulting in negative attitudes toward the species and leading to increased conservation conflict. We used multi-state occupancy modeling on the interview data to assess the ecological factors governing livestock depredation by wolves. We also assessed the socio-demographic factors that may govern the attitude of villagers toward the wolf using ordinal regression. Over the past year, 64% of respondents reported a loss of livestock, in which goats (63%) comprised the major share, followed by sheep (22%) and cattle calves (15%). Wolves tend to hunt medium-sized domestic prey (sheep and goats) that commonly graze in open agricultural areas. The estimated livestock depredation probability of wolves was 0.84 (SD = ± 0.23). Depredation probability was influenced by habitat use by wolves, the extent of agricultural areas, scrubland area, and settlement size. Respondents with prior experience of livestock loss held more negative attitudes. Shepherds held more negative attitudes than other occupations. Increases in the respondent's age and education level reflected a positive shift in attitudes toward the wolf. High economic loss caused by livestock depredation by wolves can lead to retaliatory persecution of wolves. Adequate compensation for livestock loss, along with better education and awareness can help lead to coexistence between wolves and humans in multi-use landscape of Kailadevi Wildlife Sanctuary, Rajasthan, India.
... Without spatial mapping and geo-spatial connections, spatial interactions between human and Common Leopard cannot be studied. A spatial statistical approach identifying highpriority conflict hotspot is also widely adopted (Miller 2015). Human wildlife conflict is a serious threat to the survival of endangered species and human's mankind in the world (Madden 2004). ...
... As per the incidents recorded in Division Forest Office, Syangja, Aadhikhola Rural Municipality experienced more livestock damage from Common Leopard than by any other predators; however the possible risk zonation associated in this site was unexamined. Spatial-temporal analysis explores movement of Common Leopard to the human landscapes and provides locations, where the attacks were concentrated (Miller 2015). Thus, the aim of this study was to investigate the possible geospatial connections between the livestock depredation and its surrounding impact zone due to Common leopard attack. ...
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This paper explores the status of Invasive Alien Plant Species in an urban forest of Hetauda, Nepal. The study is based on a quadrate survey (130 quadrants) within the transect line at an interval of 30 m within different six habitat types. This study identified a total of 22 invasive alien plant species representing 20 genera and 12 families out of recorded 26 species representing 24 genera and 15 families in the country. This study identified four species namely Chromolaena odorata, Eichhornia crassipes, Lantana camara and Mikania micrantha in the study area that were listed as the world’s 100 worst invasive species. The invasion was found to be negatively correlated with canopy cover. The higher the canopy cover; the lower the abundance of invasive alien species. Regarding the habitat type, settlement area had the highest number of invasive species followed by forest and roadside. Mikania micrantha, Lantana camara, Ageratum houstonianum and Chromolaena odorata were mostly abundant in forest whereas Eichhornia crassipes was highly abundant in wetlands. Mikania micrantha was mostly abundant in settlement area and Senna tora was confined to open land. The relative abundance of Ageratum conyzoides, Senna occidentalis, Ageratum adenophora, Leersia hexandra, Mimosa pudica, Bidens pilosa, Oxalis latifolia, Ipomoea carnea, Amaranthus spinosus, Argemone mexicana, Esosphaerum suaveolens were lower
... The observed and expected zones of conflict risk produced in this study offer visual guides to conservation agencies, policy makers and stakeholders (Rambaldi et al. 2006;Brown & Raymond 2007) to prioritize areas for intervention, accurately allocate financial and human resources , and improve land-use planning. Due to the success in using ENM's in the realm of HWC, the continual gathering of information and updating of the maps to track changes in conflict hotspots using longterm data is suggested (Miller et al. 2015 Species richness estimators, diversity indices, and relative cultural importance (RCI) ...
Thesis
Three major forms of hunting are believed to be on the increase in the Western Cape Province of South Africa, posing independently and synergistically some of the greatest threats to the continued survival of local wildlife. Firstly, there is growing evidence of the presence and reliance of local communities on bushmeat harvesting by means of wire-snare poaching, potentially implying severe reductions or extirpations of target species, high rates of non-target off-take, and the loss of entire communities. Secondly, human-wildlife conflict poses a threat to the livelihoods and agricultural security of many stakeholders living at the interface of human development and natural habitat in the Boland, resulting in the vast eradication of damage-causing animals (DCA’s). Finally, the use of animals and animal-derived materials in traditional medicine constitutes an important part of the belief-systems of indigenous African cultures, and is believed to be rapidly expanding. Due to the severity of the consequences reported elsewhere globally, and the general lack of local information with which to quantify the extent and impact of these hunting practices locally, structured interviews were conducted with farmers (n = 103) and labourers (n = 307) on private agricultural properties bordering protected areas (PA’s). In addition, semi-structured interviews were conducted with traditional healers (n = 36) operating from impoverished, rural communities near PA’s. Our reliance on the knowledge and experiences of local people elucidated several dynamic and interwoven social, economic and ecological factors underlying wildlife off-take, and subsequently allowed for the quantification, documentation and mapping of vertebrate off-take at the human-wildlife interface. Wire-snare poaching incidence and behaviour was strongly influenced by economic factors relating to poverty, a lack of governing regulations and punitive measures, interpersonal development, and abiotic factors such as proximity to major residential areas, roadways and PA’s. Results showed that local, male farmers managing large commercial properties affiliated with regional conservancies were most likely to rely on the lethal control of DCA’s. The highest level of tolerance by farmers was shown for primates and ungulates, while tolerance for carnivores, avifauna and invasive or feral species was comparatively lower. The spatial location of observed and expected zones of species-specific risk on a regional level was also mapped using a maximum entropy algorithm. We recorded 26 broad use-categories for 12 types of animal parts or products from 71 species used in traditional medicine. The most commonly sold items were skin pieces, oil or fat, and bones. To conclude, we conducted a synergistic assessment of species’ vulnerability to the combined impacts of the above-mentioned hunting practices, and subsequently found that leopard, grey duiker, chacma baboon, caracal, Cape porcupine, aardvark, genet spp., and cape clawless otters experience the highest potential endangerment. This study provided the first demonstration of the multifaceted and complex nature of hunting practices in the Boland Region, opening a dialogue between local communities and conservation agencies. The primary goals being to broaden our understanding of the heterogeneity in local-scale socio-ecological dynamics, to apply policies for effective management and eradication, to prioritize areas and species for intervention, to provide for more accurate allocation of conservation resources, and to provide grounds for future research in the area and elsewhere.
... Next came India and Nepal, with 20 and 14 publications respectively, focusing mostly on big cats depredation on livestock(Figure 2.4). The depredating species involved were tiger (Panthera tigris), leopard (Panthera pardus), snow leopard (Panthera uncia) and Indian lion (Panthera leo persica)(Athreya et al., 2015;Carter et al., 2012Carter et al., , 2014Chetri et al., 2017Chetri et al., , 2019Dhungana et al., 2016Dhungana et al., , 2018Hanson et al., 2020;Karanth et al., 2013;Karanth & Ranganathan, 2018;Khanal et al., 2020;Kusi et al., 2020;Lamichhane et al., 2019;Loch-Temzelides, 2021;Meena et al., 2014;Miller et al., 2015Miller et al., , 2016aMiller et al., , 2016bNaha et al., 2020;Sharma et al., 2015;Upadhyaya et al., 2020;Watts et al., 2019;Zabel et al., 2011). Twelve publications studied Italian and Tanzanian cases(Figure 2.4). ...
Thesis
Les espèces qui se nourrissent de plantes ou d’animaux élevés ou capturés par l’homme, un comportement appelé « déprédation », entraînent souvent de graves Conflits Homme-Faune sauvage (CHF). La déprédation a été signalée dans le monde entier et, dans les écosystèmes marins, elle a été développée par de nombreux grands prédateurs se nourrissant des prises de pêche, ce qui a un impact à la fois sur les activités de pêche et les interactions écologiques. Cependant, bien que les approches écosystémiques soient de plus en plus utilisées dans la gestion des pêches, les effets de la déprédation sur l’ensemble de l’écosystème sont encore rarement considérés de manière holistique. Par conséquent, cette thèse a (i) identifié les limites, manques et priorités pour le développement d’approches de modélisation intégrant la déprédation et (ii) évalué la capacité de deux approches de modélisation existantes pour caractériser les conséquences de la déprédation marine et, plus spécifiquement, comprendre les enjeux et conditions requises pour que les activités d’exploitation halieutique et les déprédateurs marins puissent co-exister. Cette thèse est composée de cinq chapitres. Le chapitre 1 présente le contexte dans lequel s’inscrit ces travaux. Le chapitre 2 identifie les principales lacunes dans les connaissances et met en évidence les principales orientations futures pour parvenir à une inclusion efficace de la déprédation dans les études de modélisation en réalisant une revue systématique. Le chapitre 3 utilise le cadre Ecopath pour évaluer les effets de la déprédation sur l'écosystème dans une étude de cas bien documentée impliquant des mammifères marins et une pêcherie commerciale. Le chapitre 4 s'appuie sur une modélisation qualitative pour évaluer les conditions de persistance d'une ressource exploitée, d'une pêcherie et d'une espèce déprédatrice dans les systèmes marins touchés par la déprédation, et la façon dont la déprédation marine affecte les réponses à long terme à des scénarios alternatifs. Enfin, la discussion générale présentée dans le chapitre 5, fournit des recommandations qui vise à mieux comprendre et prévoir les effets de la déprédation au niveau du socio-écosystème.
... Depredation risk models are most often informed solely by successful carnivore attack on livestock data (Treves et al., 2004;Miller, 2015;Hoffmann et al., 2019). These models, often termed "spatial risk models, " typically use the count of these attacks to associate abiotic and biotic conditions with depredation (Hebblewhite et al., 2005;Baruch-Mordo et al., 2008;Behdarvand et al., 2014;Miller et al., 2015;Broekhuis et al., 2017). Here, carnivore depredation data are collated across space and time to map spatial, and sometimes temporal, variation in depredation risk. ...
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Carnivore depredation of livestock is one of the primary drivers of human-carnivore conflict globally, threatening the well-being of livestock owners, and fueling large carnivore population declines. Interventions designed to reduce carnivore depredation typically center around predictions of depredation risk. However, these spatial risk models tend to be informed by data depicting the number of livestock attacked by carnivores. Importantly, such models omit key stages in the predation sequence which are required to predict predation risk, or in this case depredation risk. Applying the classic predation risk model defined by Lima and Dill demonstrates that depredation risk is dependent upon quantifying the rates at which carnivores encounter livestock before attacking. However, encounter rate is challenging to estimate, necessitating novel data collection systems. We developed and applied such a system to quantify carnivore-livestock encounters at livestock corrals (i.e., bomas) across a 9-month period in Central Kenya. Concurrently, we monitored the number of livestock attacked by carnivores at these bomas. We calculated carnivore-livestock encounter rates, attack rates, and depredation risk at the boma. We detected 1,383 instances in which carnivores encountered livestock at the bomas. However, we only recorded seven attacks. We found that the encounter rate and attack rate for spotted hyenas were almost six and three times higher than that for any other species, respectively. Consequently, spotted hyenas posed the greatest depredation risk for livestock at the boma. We argue that better understanding of carnivore-livestock encounter rates is necessary for effective prediction and mitigation of carnivore depredation of livestock.
... We present a new method to quantify predation risk that incorporates where prey may encounter but also be killed. We found it produced predictions of predation risk comparable to those based on kill-sites, the most common approach to quantify the risk of mortality (Kauffman et al., 2007;McKay et al., 2021;McPhee et al., 2012;Miller et al., 2015). ...
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Cambridge Core - Ecology and Conservation - People and Wildlife, Conflict or Co-existence? - edited by Rosie Woodroffe
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