Predation of cougar kittens following the aggregation of American black bears

Abstract

The prevalence, intensity, or outcome of interference competition and interspecific killing between predominantly solitary species operating on large spatial scales is challenging to document or test. Here, we present a detailed account of inter‐ and intraspecific interactions from contemporaneous GPS location data and in‐field investigation. In June 2018, a GPS‐collared female cougar (Puma concolor) maintained strong site fidelity for a period of 19 days, indicative of parturition behavior and establishment of a nursery site. In early July 2018, three GPS‐collared black bears (Ursus americanus) arrived at the nursery site, after which the female cougar abandoned the site. Site investigation showed that one or more bears predated an unknown number of cougar kittens. The evidence supports ecological theory suggesting that body size, mass, or group number is an important predictor of outcome. Our observation provides an example of bears potentially making risk–reward trade‐offs by eliminating a potential competitor that at the same time provisions carrion as critical food resources. These real‐time inter‐ and intraspecies competitive interactions as documented using GPS collars allow for greater insight into individual fitness and community‐level effects.