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Many predators specialize on one or several prey species that they select from the range of potential prey. Predator specialization on primary versus alternative prey is driven in part by encounter rates with prey and a predator's habitat selection. Although habitat selection changes with behavioural state, this has not been well‐recognized in the resource selection function (RSF) literature to date, often because auxiliary data on the predator's behavioural states (e.g. hunting) are absent. We monitored habitat selection of pumas Puma concolor in a multi‐prey system in northern California, where pumas specialized on black‐tailed deer Odocoileus hemionus columbianus. We employed multiple RSF analyses on different datasets to test the following three hypotheses: (1) Pumas utilize habitats in proportion to their availability; (2) Pumas select specific habitat features when killing black‐tailed deer, their primary prey; (3) Pumas do not select distinct habitats from those identified under hypothesis 1 when killing alternative prey. We found that pumas in our study selected for specific habitats and habitat features in general, but that their selection was more pronounced when killing black‐tailed deer. In summer, kill sites of deer were associated with rugged terrain, but gentle slopes and northerly aspects. In winter, pumas killed deer at low elevations, on gentle slopes and on northerly and westerly aspects. Overall, evidence suggested that pumas tracked their primary prey across seasonal migrations, which were short in distance but resulted in pronounced changes in elevation. When killing alternative prey, pumas showed little evidence of habitat selection, suggesting they may kill alternative prey opportunistically. Our results hold implications for how data should be partitioned when modelling baseline habitat selection of predators, hunting habitat selection and predation risk for prey species, as well as for how we model ecological processes such as apparent competition. [ABSTRACT FROM AUTHOR]

Cougars P uma concolor are described as 'habitat generalists', but little is known about which ecological factors drive their home range selection. For example, how do resource distributions and inter-species competition with dominant competitors (i.e. wolves, C anis lupus) over such resources, influence the distributions of cougars on the landscape? We tracked cougars using Very High Frequency (VHF; 2001 to 2005) and G lobal P ositioning S ystem ( GPS; 2006 to 2011) technology in the Southern Yellowstone Ecosystem ( SYE) in northwestern Wyoming, USA. We tested whether data type ( VHF vs. GPS), cougar sex, access to forests (refugia) or hunt opportunity explained the size of 50% and 95% kernel density estimator ( KDE) home ranges. Second, we quantified attributes of cougar home ranges and tested whether they were different from attributes of the overall study area, to address the ecological question: Do cougars select home ranges based on the availability of refugia, hunt opportunity or some combination of the two? Cougar sex and data type proved significant predictors of home range size for both 95% and 50% KDEs, and the amount of forest partly explained the size of 50% KDEs. Cougar home ranges derived from VHF data were 1.4-1.9 times larger than home ranges derived from GPS data; however, home range attributes determined from VHF and GPS data were remarkably equivalent. Female cougars selected home ranges with higher hunt opportunity than males, supporting the assumption that females primarily select home ranges with suitable prey to sustain themselves and their young. All cougars selected home ranges further from known wolf packs, providing evidence for newly established competition between resident cougars and recolonizing wolves, but did not select home ranges with greater access to landscape refugia. Our results provided evidence that cougars in the SYE select home ranges that provide high hunting opportunity and a spatial buffer that mitigates potential conflicts with a dominant competitor. [ABSTRACT FROM AUTHOR]