EARLY MIGRATION OF NORTHERN FUR-SEAL PUPS FROM ST-PAUL ISLAND, ALASKA

The early migration of northern fur seal (Callorhinus ursinus) pups wa s investigated using very high-frequency (VHF) radiotelemetry. In 1989 -1990, 184 pups were radiotagged and monitored to determine the date o f their departure from St. Paul Island, Alaska. After their departure, 70 pups were located by receiver stations in the eastern Aleutian Isl ands and by aerial surveys. Mean (+/-1 SD) time of travel between St. Paul Island and the Aleutian passes was 11 +/- 6 days (n = 63), sugges ting that, on average, pups progressed southward at the rate of ca. 36 -40 km/day. Near the Aleutians, they were distributed throughout the s tudy area from Unimak Pass to Samalga Pass, and Unimak Pass was not th e main migratory route from the Bering Sea into the North Pacific Ocea n. The pups remained dispersed as migration continued south of the Ale utian Islands. The migratory routes of northern fur seal pups in the B ering Sea and North Pacific Ocean have important implications for thei r pelagic ecology, including the type and availability of prey, oceano graphic conditions encountered, population dynamics (e.g., survival an d reproductive recruitment), and potential for interaction with human activities.