Polar bear distribution and habitat selection in western Hudson Bay.

摘要

Sea ice in Hudson Bay is melting earlier and freezing later as the climate warms, resulting in declines in the condition, survival, and population size of polar bears (Ursus maritimus) in the Western Hudson Bay population. The objectives of this study are to analyze temporal variation in distribution and quantify patterns of seasonal habitat selection for polar bears on the sea ice in Hudson Bay to determine how they respond to changing sea ice conditions. Between 1990 and 2010, 137 satellite collars were deployed on 125 adult females yielding approximately 95 000 locations. Utilization distributions and a habitat selection model were developed. Distribution shifted seasonally and annually, and habitat selection was most affected by ice concentrations. Individual differences were most apparent during ice freeze-up and break-up. This research helps us understand how changes in sea ice alter polar bear habitat use and selection, important for predicting responses to future changes.