Habitat selection when killing primary versus alternative prey species supports prey specialization in an apex predator

Abstract

© 2019 The Zoological Society of London 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.

Determining the diet of an African mesocarnivore, the caracal: scat or GPS cluster analysis?

“…By itself, scat analysis would have likely underestimated the contribution of large prey items to caracal diet. Furthermore, GPS cluster technology can also be used to investigate individual diet/specialization (Elbroch and Wittmer 2013) as well as identify habitat preferences for prey consumption (Cristescu et al 2019), making it a critical tool in studies on the effects of predators on wild and domestic prey.…”

Long‐term changes in habitat selection and prey spectrum in a reintroduced Eurasian lynx (Lynx lynx) population in Switzerland

“…Another driving factor for habitat selection in large carnivores is prey availability (Bouyer et al, 2015; Cristescu et al, 2019; Davidson et al, 2012; Oakleaf et al, 2006; Roder et al, 2020; Soyumert et al, 2019). Roe deer density has been shown to have a positive influence on lynx occurrence (Bouyer et al, 2015; Müller et al, 2014).…”

Biogeographical and ecological factors associated with kill rates of an apex predator

“…Although this aspect of puma foraging ecology may appear less relevant to wildlife managers, abundant secondary prey could impact pumaprimary prey interactions. For example, abundant secondary prey appear to be hunted opportunistically (Cristescu et al 2019) and therefore are likely included in puma diet as explained by their abundance. Increased foraging resources may also influence puma recruitment, especially survival of subadults if young animals select for non-ungulate prey during dispersal (Elbroch et al 2017a).…”