Native prey distribution and migration mediates wolf (Canis lupus) predation on domestic livestock in the Greater Yellowstone Ecosystem

Abstract

Little research has evaluated how the migration and distribution of native prey influence patterns of livestock depredation by large carnivores. Previous research suggests that the presence of native prey can increase depredation rates by attracting predators (prey tracking hypothesis). Alternatively, the absence of native prey may facilitate predation on livestock (prey scarcity hypothesis). In this study, we evaluated support for these competing hypotheses through analysis of 4 years of cattle (Bos taurus L., 1758) depredation data (n = 39 kills), 2 years of summer and fall wolf (Canis lupus L., 1758) predation and tracking data (n = 4 wolves), and 3 years of elk (Cervus elaphus L., 1758) movement data (n = 70 elk). We used logistic regression to compare the relative influence of landscape features and elk distribution on the risk of livestock depredation in areas with migratory and resident elk. Cattle depredations occurred in habitats with increased encounter rates between wolves and livestock. In resident elk areas, depredation sites were associated with elk distribution and open roads. In migratory elk areas, depredation sites were associated with wolf dens, streams, and open habitat. Patterns of carnivore–livestock conflicts are complex, and using ungulate distribution data can predict and minimize such instances.

Seasonal and inter‐annual variation in diet for gray wolves Canis lupus in Prince Albert National Park, Saskatchewan

“…Wolves are opportunistic and prey switching can occur as a result of a number of factors (that are not mutually exclusive), including in response to seasonal and environmental changes (Nelson andMech 1986, Szepanski et al 1999), the occurrence of other predators (Kortello et al 2007, Merkle et al 2017, prey vulnerability (Bergman et al 2006, Garrott et al 2007, Metz et al 2012, or changes in the abundance of prey (Garrott et al 2007, Fortin et al 2015, Sand et al 2016. We found that winter diet for wolves centered on wild ungulates, particularly deer, which is what we had predicted.…”

“…Gray wolves Canis lupus have been studied to examine both the direct and indirect effects of predation on other species, as well as conflicts with humans through predation on livestock (Wilmers et al 2003, Kortello et al 2007, Wit-tmer et al 2013, Nelson et al 2016, Santiago-Avila et al 2018. Wolf predation has been studied on wild ungulates such as deer (Odocoileus spp.…”

Rancher-reported efficacy of lethal and non-lethal livestock predation mitigation strategies for a suite of carnivores

“…These conservation strategies limited the lethal management of predators to a point where some species have recovered (Greater Yellowstone distinct population of grizzly bears delisted in 2017 8 due to recovery; gray wolves delisted nationally in 2013 with the exception of Wyoming which was delisted in 2017 9 ). Thus, while the historical human-predator paradigm has shifted from control to coexistence for some predators 10 , this paradigm shift has not occurred for all predators in all places and the complexity of livestock predation persists today 11 .…”

Reconciling livestock production and wild herbivore conservation: challenges and opportunities

“…Although the impacts of predation on livestock by carnivores is a well-documented conflict in conservation [15,51], the extent to which the occurrence of these impacts is mediated by wild herbivore prey remains unknown. Nelson et al [59] put forward two mechanisms to describe this interaction. The prey tracking hypothesis states that carnivores are attracted to their wild prey but kill livestock as a by-product where both types of herbivore co-occur [59].…”