Assessing Spatial Factors Affecting Predation Risk to Boreal Caribou Calves: Implications for Management

In 2013, we completed the last year of data collection for the project. Across the project’s three years, we collected GPS data from 57 female caribou, 19 wolves (Canis lupus) and 19 black bears (Ursus americanus). We used these data to compare annual rates of parturition and calf survival as well to evaluate caribou and predator habitat selection during the calving season. For caribou, we further evaluated relative calving habitat quality by determining how variation in maternal habitat selection impacts neonate survival.
In the past year, we developed novel movement-based methods for inferring parturition and neonate survival rates. For 2013, we followed the movements of 30 females and estimated a parturition rate of 60-77%. This range was similar to our predicted rate in 2012 but below our 2011 estimate (80%) and lower than rates recorded in other studies. Adverse snow conditions in late winter and early spring may have contributed to the low rate of 2013 and likely caused the peak calving period to be delayed by approximately one week compared to the study’s previous two years.