Document Type

Article

Publication Date

July 2018

Publication Title

Ecosphere

Volume

9

Issue Number

7

DOI

10.1002/ecs2.2301

Keywords

area restricted search, foraging habitat, foraging strategy, Gulf of California, k-means clustering, Northwestern Hawaiian Islands, oceanographic characteristics, Palmyra Atoll, Sula dactylatra, Sula leucogaster, Sula nebouxii, Sula sula

Disciplines

Marine Biology | Ornithology

Abstract

Due to rapidly changing global environmental conditions, many animals are now experiencing concurrent changes in both resource availability and the foraging cues associated with finding those resources. By employing flexible, plastic foraging strategies that use different types of environmental foraging cues, animals could adapt to these novel future environments. To evaluate the extent to which such flexibility and plasticity exist, we analyzed a large dataset of a clade (Sulidae; the boobies) of widespread aerial tropical predators that feed in highly variable marine habitats. These surface foragers are typical of many ocean predators that face dynamic and patchy foraging environments and use a combination of static and ephemeral oceanographic features to locate prey. We compared foraging habitats and behaviors of four species at seven colonies in the eastern and central Pacific Ocean that varied greatly in depth, topography, and primary productivity. Foraging behaviors, recorded by GPS-tracking tags, were compared to remotely sensed environmental features, to characterize habitat-behavior interactions. K-means clustering grouped environmental characteristics into five habitat clusters across the seven sites. We found that boobies relied on a combination of static and ephemeral cues, especially depth, chlorophyll-a concentrations, and sea surface height (ocean surface topography). Notably, foraging behaviors were strongly predicted by local oceanographic habitats across species and sites, suggesting a high degree of behavioral plasticity in use of different foraging cues. Flexibility allows these top predators to adapt to, and exploit, static and ephemeral oceanic features. Plasticity may well facilitate these species, and other similarly dynamic foragers, to cope with increasingly changing environmental conditions.

Comments

This article was published in Ecosphere, 9(7):e02301, 2018, and can also be found online at this link. © 2018 The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.

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