Factors affecting gray wolf (Canis lupus) encounter rate with elk (Cervus elaphus) in Yellowstone National Park

Despite encounter rates being a key component of kill rate, few studies of large carnivore predation have quantified encounter rates with prey, the factors that influence them, and the relationship between encounter rate and kill rate. The study’s primary motivation was to determine the relationship between prey density and encounter rate in understanding the mechanism behind the functional response. Elk (Cervus elaphus Linnaeus, 1758) population decline and variable weather in northern Yellowstone National Park (YNP) provided an opportunity to examine how these factors influenced wolf (Canis lupus Linnaeus, 1758) encounter rates with elk. We explored how factors associated with wolf-kill rate and encounter rate in other systems (season, elk density, elk-group density, average elk-group size, snow depth, wolf-pack size and territory size) influenced wolf-elk encounter rate in YNP. Elk density was the only factor significantly correlated with wolf-elk encounter rate, and we found a non-linear density-depen...