Entanglement of Pinnipeds in Synthetic Materials at South-east Farallon Island, California, 1976–1998

Abstract

Entanglement records of hauled out pinnipeds are useful for monitoring trends in impacts of synthetic materials, a principal contaminant, upon pinniped populations. This report documents entanglement of five species (California Sea Lions, Northern Elephant Seals, Steller Sea Lions, Pacific Harbor Seals, and Northern Fur Seals) at South-east Farallon Island (SEFI), an island in Northern California, 1976–1998, when a total of 914 pinnipeds were observed entangled in or with body constrictions from synthetic material. There was a significant decrease in entangled Northern Elephant Seals over the study period. Of the 27 Steller Sea Lions observed entangled, 37% were adult Steller Sea Lions entangled in salmon fishing gear. This report highlights an ongoing problem of entanglement of pinnipeds in synthetic materials in Northern California.