Sightings and Strandings of Guadalupe Fur Seals in Central and Northern California, 1988-1995

Abstract

The Guadalupe fur seal ( Arctocephalus townsendi ) was hunted to near extinction before its natural history was well known. The last known population is currently centered on Guadalupe Island, Mexico, but in recent years northern extralimital records from California have become more frequent. We report 14 new records (3 adults, 11 juveniles) of Guadalupe fur seals stranded (nine) or sighted (five) along the central and northern coast of California. These northern records appear to correspond with El Nino events, seasonal currents in California, and to dispersal behavior in this species. Dietary items retrieved from stomachs and feces included otoliths from Citharichthys sordidus, Lampanyctus, Protomyctophum , and Scopelogadus , and beaks of the squids Loligo opalescens, Gonatopsis , and Onychoteuthis borealojaponica . Emaciation commonly was associated with stranding, but other findings included an umbilical hernia, septicemia, and bacterial pneumonia. Three of the stranded individuals had experienced entanglement in fishing gear or marine debris.