Introduced wild pigs affect the foraging ecology of a native predator as both prey and scavenger

Introduced species can disrupt trophic interactions by acting as novel predators, prey, or scavengers. Predicting the impacts of these disruptions can be integral to the conservation of native species and the maintenance of ecological function, but is challenging, especially for species involved in multiple trophic interactions. Wild pigs Sus scrofa are a widely introduced ungulate that can function as prey, predator, and scavenger, and disrupt ecosystems through many pathways. One underexplored avenue is how wild pigs alter predator–prey dynamics of mammalian carnivores. We explored how wild pigs affect cougar Puma concolor foraging ecology as both prey for cougars and scavengers of cougar kills. We monitored cougars in an area with wild pigs to evaluate impacts on cougar habitat selection, diet, and feeding behavior. We also monitored wild pigs scavenging at cougar kills to understand if scavenging by pigs affects cougar feeding behavior or kill rates. Habitat selection patterns indicated that cougars selected for areas based on both landscape factors and prey density, but selection was stronger for native black‐tailed deer Odocoileus hemionus columbianus than for pigs. We also documented that wild pigs, especially juveniles, were an important secondary prey item for cougars. Finally, we observed that wild pigs scavenged large prey items killed by cougars, which led to reduced feeding time by cougars at individual kills. However, wild pigs did not scavenge frequently enough to affect cougar kill rates. Our research highlights multiple impacts of wild pigs on cougar ecology, both as prey and as scavenger, to illustrate how wild pigs disrupt ecosystems. Areas with a higher density of pigs or lower density of native prey would likely see stronger impacts of wild pigs on predator–prey interactions, and management of wild pigs should account for these interactions, especially when native predators or prey are species of conservation concern.