Seals in western Hudson Bay: Assessing proportions in natural and human harvests using genetic methods
LE3 .A278 2017
Peterson, Stephen D.
Bachelor of Science
Earth and Environmental Science
Earth & Environmental Sciences
Arctic seals are of great importance to polar bears (Ursus maritimus) and humans, however the ecosystem that supports them is changing as the climate warms. In spite of the importance of seals, little is known about their abundance or the relative abundance of each species. The proportion of seals harvested by hunters and seals killed by polar bears could be used to infer the naturally occurring relative abundance in Hudson Bay. This study compares 104 seal samples harvested by hunters between 2014-2016 and 12 seal samples killed by polar bears in 2014. All samples are from Hudson Bay near Churchill, Manitoba. Analysis of the samples determined which species: harbour seal (Phoca vitulina), ringed seal (Pusa ispida), and bearded seal (Erignathus barbatus) are killed by polar bears and humans. I developed a restriction enzyme digest to determine the species of these samples, quickly and cheaply. I found that there was no difference (p=0.998, Freeman-Halton extension of the Fisher’s exact test) between the proportion of seals harvested by humans or by polar bears, which suggests that both polar bears and humans are harvesting seals in the proportions with which they are encountered in this area. The data also provided insight into polar bear diet, in that they prefer ringed seals over bearded and harbour seals. Understanding predators and their prey in the Arctic is important as climate warming and changes occur in sea ice habitat that seals and polar bears rely on.
The author grants permission to the University Librarian at Acadia University to reproduce, loan or distribute copies of my thesis in microform, paper or electronic formats on a non-profit basis. The author retains the copyright of the thesis.