Post-conflict movements of polar bears in western Hudson Bay, Canada

Abstract

Human-carnivore conflicts have increased as habitat has been affected by development and climate change. Understanding how management-decisions affect the behaviour of animals may reduce conflicts. We examined how biological factors, sea ice conditions, and management decisions affected the autumn migratory movement of polar bears (Ursus maritimus) from 2016 to 2021 following their capture near Churchill, Manitoba, Canada, and release after a mean of 20 days (SE 2) in a holding facility. We deployed eartag satellite transmitters on 63 bears (26 males, 37 females), with 49% adults (> 5 years old), 48% subadults (3-5 years old), and 3% < 2-years-old. We compared variation in on-ice departure of bears released post-conflict (conflict) to adult females without a conflict history (non-conflict). Conflict bears departed 89 km further north (mean = 59.7°N, SE 0.2) of non-conflict bears (mean = 58.9°N, SE 0.1). Bears released later during the migratory period were less likely to re-enter a community at a rate of 5.9-6.4% per day. Of 69 releases (6 individuals requiring multiple releases), 12 bears re-entered Churchill and 13 entered Arviat, Nunavut. We suggest that the holding facility was effective at preventing additional conflicts and individuals with a high likelihood of recidivism should be held longer.