PARENT SESSION
Poster Session 25: Mammalian Ecology
Thursday, August 11, 5:00 PM - 6:30 PM, Exhibit Hall 220 A-E, Level 2, Palais des congrès de Montréal

Linking moose habitat selection to limiting factors.

Dussault, Christian^{*,1, 2}, Ouellet, Jean-Pierre¹, Courtois, Réhaume², Huot, Jean³, Breton, Laurier², Jolicoeur, Hélène², ¹ Département de biologie, Rimouski, Québec, Canada² Direction de la recherche sur la faune, Québec, Québec, Canada³ Département de biologie, Sainte-Foy, Québec, Canada

ABSTRACT- It has been suggested that patterns of habitat selection of animals across spatial scales should reflect the factors limiting individual fitness in a hierarchical fashion. Animals should thus select habitats that permit avoidance of the most important limiting factor at large spatial scales while the influence of less important factors should only be evident at fine scales. We tested this hypothesis by investigating moose (iAlces alces/i) habitat selection using GPS telemetry in an area where the main factors limiting moose numbers were likely (in order of decreasing importance) predation risk, food availability and snow. At the landscape scale, we predicted that moose would prefer areas where the likelihood of encountering wolves was low or areas where habitats providing protection from predation were dominant. At the home-range scale, we predicted that moose selection would be driven by food availability and snow depth. Wolf territories were delineated using telemetry locations and the study area was divided into 3 sectors that differed in terms of annual snowfall. Vegetation surveys yielded 6 habitat categories that differed with respect to food availability, and shelter from predation or snow. Our results broadly supported the hypothesis but moose reacted to several factors at both scales. At the landscape scale, moose were spatially segregated from wolves by avoiding areas receiving the lowest snowfall, but they also preferentially established their home range in areas where shelter from snow bordered habitat types providing abundant food. At the home-range scale, moose also traded off food availability with avoidance of deep snow and predation risk. During winter, moose increased use of stands providing shelter from snow along edges with stands providing abundant food. Habitat selection patterns of females with calves differed from that of solitary moose, the former being primarily associated with habitats providing protection from predation. Animals should attempt to minimize detrimental effects of the main limiting factors when possible at the large scale. However, animals are expected to make trade offs to minimise the influence of several potential limiting factors when avoidance of the main factor implies an adverse effect.

Key words: Habitat selection, Limiting factors, Moose, Scale