For the first part of my thesis, I investigated the influence of broad- and local-scale environmental factors such as weather, topography, anthropogenic features (i.e., roads and harvest blocks), and the availability of food resources on the timing of den entry and den exit of grizzly bears, and on their selection of dens in the boreal forest and Rocky Mountains of Alberta, Canada. The timing of den entry and den exit of grizzly bears was driven by sex and reproductive status, food availability in autumn, winter precipitation, and spring temperature. At the landscape scale, grizzly bears avoided wetlands and chose high-elevation dry conifer stands with abundant high-quality spring foods to dig their dens. Within their home-ranges, grizzly bears chose areas with low densities of roads to dig their dens, and at the local scale, grizzly bears also preferred dense conifer stands generally associated with little high-quality autumn food. For the second part of my thesis, I investigated the influence of thermoregulation on patterns of habitat selection during the active season. This chapter highlights the often overlooked thermal constraints of large mammals faced with increasing ambient temperatures. During the active season, grizzly bear habitat selection followed a daily and seasonal pattern that was influenced by ambient temperature, and males showed a stronger response to warm temperatures compared to females. With increasing ambient temperatures, male and female grizzly bears adjusted their habitat selection pattern by increasingly foraging within open stands with abundant food resources during the coolest periods of the day. At the same time, male and female grizzly bears decreased their selection for these open stands during the warmest periods of the day. In summary, my thesis increases our understanding of the respective roles of individual and environmental factors on hibernation behaviour, habitat selection, and constraints associated with thermoregulation for grizzly bears. My thesis offers (1) important advancements towards the long-term conservation of grizzly bear populations in Alberta, Canada, (2) an improved understanding of the factors regulating the distribution of individuals in time and space, and (3) an enhanced ability to predict the potential impacts of climate change on large mammal species.
featured chapters & publications
Timing of den entry & exit
Drivers of hibernation: Linking food and weather to denning behaviour of grizzly bears.
Behavioral Ecology and Sociobiology
Staying cool in a changing landscape: The influence of maximum daily ambient temperature on grizzly bear habitat selection. Oecologia
Assessing den selection and den characteristics of grizzly Bears. Journal of Wildlife Management
Den selection by grizzly bear on a managed landscape. Journal of Mammalogy