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

Human-carnivore conflicts have increased as habitat has been affected by development and climate change. Understanding how biological factors, environment, and 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 Phipps, 1774) 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 year old), and 3% <2-year 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 = 59.7N, SE 0.2) of non-conflict bears (mean = 58.9N, 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.

Automated summary

Human-carnivore conflicts have been on the rise due to habitat disruption caused by development and climate change. This study focused on the autumn migratory movement of polar bears and explored the impact of biological factors, sea ice conditions, and management decisions. The findings suggest that conflict bears tend to migrate further north and bears released later in the migratory period are less likely to re-enter communities.