Interspecific and intraspecific foraging differentiation of neighbouring tropical seabirds

作者：Rhiannon Austin, Federico De Pascalis, Stephen C. Votier, Jane Haakonsson, John P. Y. Arnould, Gina Ebanks‐Petrie, Jason Newton, Jessica C. Harvey, Jonathan A. Green · 发表于：Movement Ecology · 年份：2021 · DOI：10.1186/s40462-021-00251-z · 被引用次数：27 · 研究领域：Avian ecology and behavior、Animal Behavior and Reproduction、Animal Ecology and Behavior Studies

BACKGROUND: Social interactions, reproductive demands and intrinsic constraints all influence foraging decisions in animals. Understanding the relative importance of these factors in shaping the way that coexisting species within communities use and partition resources is central to knowledge of ecological and evolutionary processes. However, in marine environments, our understanding of the mechanisms that lead to and allow coexistence is limited, particularly in the tropics. METHODS: Using simultaneous data from a suite of animal-borne data loggers (GPS, depth recorders, immersion and video), dietary samples and stable isotopes, we investigated interspecific and intraspecific differences in foraging of two closely-related seabird species (the red-footed booby and brown booby) from neighbouring colonies on the Cayman Islands in the Caribbean. RESULTS: The two species employed notably different foraging strategies, with marked spatial segregation, but limited evidence of interspecific dietary partitioning. The larger-bodied brown booby foraged within neritic waters, with the smaller-bodied red-footed booby travelling further offshore. Almost no sex differences were detected in foraging behaviour of red-footed boobies, while male and female brown boobies differed in their habitat use, foraging characteristics and dietary contributions. We suggest that these behavioural differences may relate to size dimorphism and competition: In the small brown booby population (n < 200 indivi...