Defense Date


Document Type


Degree Type

Master of Science

Degree Name

Marine Science

First Advisor

Amy C. Hirons, Ph.D.

Second Advisor

David W. Kerstetter, Ph.D.


Sea otter populations in Alaskan waters have presented both growth and declines over the past years, which some researchers have attributed to changes in predator-prey dynamics. This project utilized stable isotope ratios to determine potential differences in the trophic ecology dynamics of the northern sea otter (Enhydra lutris kenyoni) in southern Alaskan waters. Stable carbon (δ13C) and nitrogen (δ15N) isotope ratios from Prince William Sound otters, a relatively stable population, were compared to endangered sea otter populations from the Alaska Peninsula and Aleutian Island Archipelago. Location was a significant factor differentiating trophic ecology between southcentral and southwestern sea otter populations (p