Comparative Behavioral Biology Presents
Postdoctoral Fellow, Chicago Zoological Society, Brookfield Zoo
“Shadowed by Scale: Behavioral niche partitioning between two albatross species revealed by fine-scale GPS data”
Wednesday, January 25 @ 12pm
in BPSB 122
ABSTRACT: As synchronous, colonial breeders, Hawaiian albatross face additional constraints during the chick brood phase: 1) an increase in both intra- and interspecific resource competition and 2) a spatial restriction to poorer-quality subtropical habitat. We combined residence times, landing rates, and drift sinuosities from albatross movements collected with GPS data-loggers to describe the fine-scale foraging behavior of breeding black-footed (Phoebastria nigripes, n = 20) and Laysan (P. immutabilis, n = 16) albatrosses and to identify behaviors that reflect niche partitioning. Birds foraged both in direct flight and in area-restricted search, but direct flight foraging was the most prevalent, supporting the idea that spatial analyses dependent upon turn angles and speeds may underestimate important foraging strategies in albatross. Highly tortuous drifts were also common, suggesting that both species also often employed a drifting “sit-and- wait” tactic, a result reinforced by recent diet observations. Both species had similar time-activity budgets, but subtle differences emerged when examined under diurnal and lunar influences.