Divergent foraging habitat preferences between summer-breeding and winter-breeding Procellaria petrels

• Main Authors: Bentley, Lily K, Manica, Andrea, Dilley, Ben J, Ryan, Peter G, Phillips, Richard A
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2022
• Subjects: Antarctica; congeners; movement ecology; seabird; Antarctic; Austral; Sandwich Islands; South Sandwich Islands; South Georgia; Bird Island; Gough; Antarc*; British Antarctic Survey
• Online Access: https://www.repository.cam.ac.uk/handle/1810/342706; https://doi.org/10.17863/CAM.90120

Funder: British Antarctic Survey; Id: http://dx.doi.org/10.13039/501100007849 Funder: Foreign and Commonwealth Office; Id: http://dx.doi.org/10.13039/501100000617 Funder: Gates Cambridge Trust; Id: http://dx.doi.org/10.13039/501100005370 Funder: Government of South Georgia and the South Sandwich Islands Funder: South African National Antarctic Program <jats:p>Foraging niche specialization is thought to occur when different members of speciose communities divide resources in either time or space. Here we compared habitat preferences of the congeneric Grey Petrel <jats:italic>Procellaria cinerea</jats:italic> and White‐chinned Petrel <jats:italic>Procellaria aequinoctialis</jats:italic>, tracked in the same calendar year using GPS loggers from Gough Island and Bird Island (South Georgia), respectively. We identified periods of active foraging and determined habitat characteristics using remote‐sensing data. Although these highly pelagic species could potentially overlap at sea across large areas, they showed markedly different foraging preferences during their incubation periods, which are temporally offset because Grey Petrels breed during the austral winter. Grey Petrels foraged mostly in pelagic cold‐water areas to the north‐west of South Georgia, whereas White‐chinned Petrels foraged almost exclusively in the warm, shallow waters of the Patagonian Shelf. Within each species, foraging habitat characteristics were highly consistent. Our results demonstrate the diversity of habitat preferences within genera, and provide further evidence that colony‐specific information on habitat preference is crucial to identify important feeding areas for pelagic predators.</jats:p>