Satellite telemetry studies of the movements of seabirds are now common and have revealed impressive flight capabilities and extensive distributions among individuals of many species at sea. Linking seabird movements with environmental conditions over vast expanses of the world’s open ocean, however, remains difficult. We applied a new method for quantifying the movements of far-ranging seabirds in relation to ocean winds measured by the SeaWinds scatterometer onboard the QuikSCAT satellite. We apply vector correlation to evaluate how the trajectories (ground speed and direction) of Hawaiian Petrels outfitted with satellite transmitters during the summer chick-rearing period were related to ocean winds. During three consecutive breeding seasons (2006–08), 17 birds from two colonies (Maui and Lanai) completed 23 clockwise, circular, long-distance 9716 ± 418 SE km foraging trips lasting 18.0 ± 0.9 days. We suggest that low variability in foraging trip distance (cv = 0.17) and duration (cv = 0.19) results from the petrels’ reliance on quartering tail-winds as they circle large anti-cyclones located to the north of Hawaii in the central-eastern North Pacific. Two tagged individuals classified as non-chick provisioning adults attending nest sites, and one individual outfitted with a transmitter who was not recaptured (all lost transmitters at sea) completed long-range, clockwise excursions into the North Pacific, similar to the completed loops of chick provisioning adults, but once southeast of the main Hawaiian Islands, all three exhibited meandering paths south to the North Equatorial Counter Current (NECC) and west as far as the Philippine Sea. Limited data from these individuals indicate that adults may seek productivity associated with the NECC and western Pacific during the winter non-breeding season.

This product is associated with the following project:
Seabird Studies at WERC

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