Polar Bear Conservation in a Period of Arctic Warming

• Author / Creator

  Hamilton, Stephen

• Polar bear conservation faces significant challenges under Arctic warming, especially with respect to habitat loss and the resulting impacts on their seasonal energetic uptake and maintenance. Polar bears rely on sea ice for hunting, mating, denning, and rearing of offspring, and the availability of ice, both spatially and temporally, influences their fitness and survival. The research collected in this thesis includes an assessment of the global polar bear population, identifying gaps in the knowledge, and presenting a model linking polar bear density to prey diversity, providing estimates for missing subpopulations. The majority of subpopulations are found to be vulnerable to continued Arctic warming based on decadal-scale changes to sea ice and population size. A sea ice projection model for the Canadian Arctic Archipelago provided the means to estimate how sea ice degradation and loss may affect polar bears through the 21st century. Projections suggest that, without curbing greenhouse gas emissions, ice conditions in the Archipelago will shift away from a multi-year sea ice regime, and lengthening ice-free conditions will harm polar bear reproductive success and increase starvation rates. An analysis of movement patterns of adult and subadult, males and female polar bears, in the southern Beaufort Sea suggests that the ice-free season is associated with higher movement rates, thus greater demands on energy stores during a season that is expected to get longer with future warming. An assessment of time and space use of harvest risk areas derived from historical harvest locations found that subadult males were more often in risk areas than other age and sex classes, although they avoided the highest risk areas. Landfast ice in the low-risk areas was decreasing faster over time, with the possibility to concentrate polar bears into areas of higher risk to harvest under continued Arctic warming.

• Subjects / Keywords

  • polar bear
  • arctic
  • global warming
  • conservation
  • population
  • sea ice
  • movement
  • harvest
  • Beaufort Sea

• Graduation date

  Spring 2023

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/r3-t0gd-3567

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.