Linking moose habitat selection to limiting factors

Abstract

H. 2005. Linking moose habitat selection to limiting factors. Á/ Ecography 28: 619 Á/628.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 Alces alces 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 because moose reacted to several factors at each scale. 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 associated primarily 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, when the risk associated with several potential limiting factors varies with scale, we should expect animals to make trade-offs among these.

Habitat use and selection by male and female moose (Alces alces) in a boreal landscape.

“…Average annual range sizes o f moose in this study were similar to those in northern Canada and Alaska (Doerr 1983, Cederlund and Okarma 1988, Cederlund and Sand 1994, Dussault et al 2005b). In the South Canol area o f Yukon, we observed significant differences in size of seasonal ranges.…”

A comparison of forest resource inventory, provincial land cover maps and field surveys for wildlife habitat analysis in the Great Lakes – St. Lawrence forest

“…An understanding of the abundance and distribution of these tree species is therefore important to understanding demographics of black bear populations in the Great Lakes -St. Lawrence forest. Hemlock stands may be an important source of cover for moose in our study areas (Minzey andRobinson 1991, Forbes andTheberge 1993), and distribution of cover can limit the range of available feeding area and therefore the quantity of viable moose habitat (Thompson and Vukelich 1981, Allen et al 1991, Dussault et al 2005. In the same region of Ontario, life history traits of other wildlife species, such as deer mice (Peromyscus maniculatus Wagner), are also strongly influenced by seed crops (Falls et al 2007), and abundance of these prey species influences population growth of their predators (Fryxell et al 1999).…”

Home ranges, habitat and body mass: simple correlates of home range size in ungulates

“…However, within a habitat different diets may result in different energy trade-offs [59], or alternatively the habitat may determine the diet [60], making the distinction between the two important. Moreover, habitat affects the mortality risk associated with predation [39,61], and exposure to extreme weather conditions [62,63]. Habitat composition also affects movement among foraging patches [64,65], and thereby factors such as resource encounter rate and scale of perception [66].…”