Recolonizing carnivores: Is cougar predation behaviorally mediated by bears? Cougar Killsite Data

Conservation and management efforts have resulted in population increases and range expansions for some apex predators, potentially changing trophic cascades and predatory behavior. Changes in sympatric carnivore and dominant scavenger populations provide opportunities to assess how carnivores affect one another. Cougars (Puma concolor) were the apex predator in the Great Basin of Nevada, USA, for over 80 years. Black bears (Ursus americanus) have recently recolonized the Great Basin and are known to heavily scavenge on cougar kills; however, competitive interactions between the two species in the Great Basin have yet to be examined. We investigated kill sites of 31 cougars between 2009 and 2017 across a range of bear densities to evaluate the impacts of sympatric, recolonizing bears on cougar foraging behavior. We modeled the variation in feeding bout duration (number of nights spent feeding on a prey item) and the proportion of primary prey, mule deer (Odocoileus hemionus), in cougar ...