Nocturnal and diurnal foraging activity of Hawaiian Albatrosses detected with a new immersion monitor

We used a new immersion monitor to study the foraging movements of two spec ies of albatrosses that nest in the Hawaiian Islands. The monitors showed t hat breeding male Black-footed Albatrosses (Phoebastria nigripes) land on t he water more frequently during the day than at night. Breeding male Laysan Albatross (Phoebastria immutabilis) behavior was more variable and also sh owed a diurnal bias. We found no evidence of a nocturnal foraging bias in e ither species; in particular, these species do not seem to be limited to li ve capture of nocturnally available squid. Such squid may, nonetheless, con tribute to the diet as a result of scavenging.