Habitat Utilization By Sea Otters (Enhydra Lutris) In Port Valdez, Prince William Sound, Alaska

Abstract

Environmental constraints and human activity influence sea otter habitat use in Port Valdez. Nonetheless, a small subpopulation consistently uses food and space resources there. Otter number, distribution, response to human activity, energetics, and behavior in the Alyeska Marine Terminal (an industrial area) were compared to Shoup Bay (an area with low human activity) from September 1989 to September 1991. Low numbers averaged 102 otters monthly and were predominantly juvenile males. Shoup Bay densities were higher than the Terminal. Terminal boat traffic was more than twice Shoup Bay, resulting in more otter encounters with moving boats and more behavioral changes. Petroleum hydrocarbon levels were low or undetectable in mussels, the main otter prey in the port. Diets varied more in the Terminal than Shoup Bay. Despite lower mussel caloric content in Shoup Bay, otters spent significantly more time feeding at the Terminal. Time-activity budgets in Shoup Bay were more variable. <p>