Behavior and Survival of Rehabilitated Surf Scoters (Melanitta Perspicillata) Oiled during the Cosco Busan Spill on San Francisco Bay

ABSTRACT Following the spill of bunker oil from the M/V Cosco Busan into San Francisco Bay, California on 7 November 2007, we evaluated the foraging characteristics, survival and movements of surf scoters (Melanitta perspicillata) that had been rehabilitated following formal rehabilitation protocols through the use of intracoelomic implants of radio transmitters and aerial/land based tracking. We compared these behavioral attributes of oiled surf scoters to surf scoters that were not oiled, but instead captured and released or put through the same rehabilitation procedure (thus separating the rehabilitation/captivity effects from the oiling). Initial behavioral observations have shown that mean home range size was greatest for unrehabilitated birds, and oiled birds were observed closer to shore than either the un-oiled rehabilitated or control group. Survival was also seen to differ among treatment groups and over encounter occasions, with cumulative winter survival estimates being lowest for oiled birds ...