Hanging out at the club: Breeding status and territoriality affect individual space use, multi‐species overlap and pathogen transmission risk at a seabird colony

• Published in: Functional Ecology
• Main Authors: Lamb, Juliet, Tornos, Jeremy, Dedet, Romain, Gantelet, Hubert, Keck, Nicolas, Baron, Juliette, Bely, Marine, Clessin, Augustin, Flechet, Aline, Gamble, Amandine, Boulinier, Thierry
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2023
• Subjects: Indian; Amsterdam Island; Brown Skua
• Online Access: https://eprints.gla.ac.uk/294937/; https://eprints.gla.ac.uk/294937/1/294937.pdf

1. Wildlife movement ecology often focuses on breeders, whose territorial attachments facilitate trapping and following individuals over time. This leads to incomplete understanding of movements of individuals not actively breeding due to age, breeding failure, subordinance, and other factors. These individuals are often present in breeding populations and contribute to processes such as competition and pathogen spread. Therefore, excluding them from movement ecology studies could bias or mask important spatial dynamics. 2. Loafing areas offer an alternative to breeding sites for capturing and tracking individuals. Such sites may allow for sampling individuals regardless of breeding status, while also avoiding disturbance of sensitive breeding areas. However, little is known about the breeding status of individuals attending loafing sites, or how their movements compare to those of breeders captured at nests. 3. We captured a seabird, the brown skua, attending either nests or loafing areas (‘clubs’) at a multi-species seabird breeding site on Amsterdam Island (southern Indian Ocean). We outfitted skuas with GPS-UHF transmitters and inferred breeding statuses of individuals captured at clubs using movement patterns of breeders captured at nests. We then compared space use and activity patterns between breeders and nonbreeders. 4. Both breeding and nonbreeding skuas attended clubs. Nonbreeders ranged more widely, were more active, and overlapped more with other seabirds and marine mammals than did breeders. Moreover, some nonbreeders occupied fixed territories and displayed more restricted movements than those without territories. Nonbreeders became less active over the breeding season, while activity of breeders remained stable. Nonbreeding skuas were exposed to the agent of avian cholera at similar rates to breeders but were more likely to forage in breeding areas of the endangered endemic Amsterdam albatross, increasing opportunities for interspecific pathogen transmission. 5. Our results show that inference ...