University of Alaska Anchorage
Mike Graduated in May 2005 with a MS of Biological Sciences.
PATTERN MATTERS: CHANGES IN THE ORGANIZATION OF SWIMMING AND DIVING BEHAVIOR BY STELLER SEA LION JUVENILES IN ALASKA
Steller sea lions (Eumetopias jubatus) are generalist predators within coastal Alaska. Juveniles enjoy a long but variable-length period of nutritional dependence, during which the extent of independent foraging is unknown. This study attempted to identify the shift to independence by examining changes in swimming and diving behavior of juveniles as they approached the end of their first year, and comparing this behavior between pups and juveniles. Using optimal foraging theory as the basis for inference, it was predicted that change in foraging would be reflected in changes in the temporal organization of behavior. Results indicated that young sea lions changed the temporal distribution of behavior as they grew older, suggesting transition to independent foraging. Unlike younger pups, older juveniles also showed stronger temporal organization of behavior at the individual dive, dive bout and at-sea trip scale, as expected for an optimally foraging predator upon patchily-distributed prey.
|Last update 10/27/09|