Pinniped Abundance and Distribution in the San Juan Channel, and Haulout Patterns of Steller Sea Lions at Cattle Point

Abstract

Two species of pinnipeds were focused on in this study, the Harbor seal (Phoca vitulina), and the Steller sea lion (Eumatopias jubatus). In this study the abundance and distribution of Harbor seals and Steller sea lions in the San Juan Channel was studied in fall 2014 using the strip transect method. Results were compared with data collected by previous Pelagic Ecosystem Function Research Apprenticeship students from fall 2007- 2013. Harbor seal numbers were found to be stable, but steller sea lion’s numbers have been declining for the past three years. Over the course of fall 2014 harbor seal numbers declined, possibly due to the fall transition, while steller sea lion numbers stayed low throughout the season. Steller sea lion haulout patterns were also examined at Cattle Pass, Washington, and found to have a correlation with current speed.