First Year Progress on the Reintroduction of Sea Otters to San Nicolas Island
R.L. Brownell
U.S. Fish and Wildlife Service, Piedras Blancas Research Station, San
Simeon, CA
Sea otters (Enhydra lutris) were captured along the central
California coast between August 1987 and June 1988 and translocated to San Nicolas Island
(SNI). A total of 124 sea otters were collected, but because of sex and size limitations,
only 74 were retained and transported by vehicle to the Monterey Bay Aquarium (MBA). After a
few days at the MBA, the sea otters were flown to SNI. Four sea otters died at the Aquarium
from stress, and an additional animal was returned to its capture site and released. The
remaining 69 Sea Otters (16 males and 53 females) were taken to SNI on 13 flights and
released. By the end of July 1988, 20 sea otters were being routinely identified at the
island, mostly along the northwestern side. The fate of 23 animals is known: 11 returned to
the central coast, I was captured in southern California and returned to the mainland
population, 3 died at the island from stress, 2 died on the mainland, 3 perished in fishing
gear, and 3 that were radio-tagged were presumed dead due to their sudden disappearance. The
fate of the remaining 26 (69 minus 20 and 23) is unknown. Information on the distribution and
movement patterns of the translocated sea otters was gathered at SNI, in addition to
information on their activity budgets, foraging behavior, and diet. In late September 1988,
translocation activity was begun for the second year. This work is in progress and will be
briefly reviewed.