Jordan F. D., Shaffer S. A., Conners M. G., Stepanuk J. E. F., Gilmour M. E., Clatterbuck C. A., Hazen E. L., Palacios D. M., Tremblay Yann, Antolos M., Foley D. G., Bograd S. J., Costa D. P., Thorne L. H. (2022). Divergent post-breeding spatial habitat use of Laysan and black-footed albatross. Frontiers in Ecology and Evolution, 10, p. 1028317 [18 p.]. ISSN 2296-701X.
Titre du document
Divergent post-breeding spatial habitat use of Laysan and black-footed albatross
Année de publication
2022
Auteurs
Jordan F. D., Shaffer S. A., Conners M. G., Stepanuk J. E. F., Gilmour M. E., Clatterbuck C. A., Hazen E. L., Palacios D. M., Tremblay Yann, Antolos M., Foley D. G., Bograd S. J., Costa D. P., Thorne L. H.
Source
Frontiers in Ecology and Evolution, 2022,
10, p. 1028317 [18 p.] ISSN 2296-701X
Understanding the at-sea movements of wide-ranging seabird species throughout their annual cycle is essential for their conservation and management. Habitat use and resource partitioning of Laysan (Phoebastria immutabills) and black-footed (Phoebastria nigripes) albatross are well-described during the breeding period but are less understood during the post-breeding period, which represents similar to 40% of their annual cycle. Resource partitioning may be reduced during post-breeding, when birds are not constrained to return to the nest site regularly and can disperse to reduce competitive pressure. We assessed the degree of spatial segregation in the post-breeding distributions of Laysan (n=82) and black-footed albatrosses (n=61) using geolocator tags between 2008 and 2012 from two large breeding colonies in the Northwestern Hawaiian Islands, Midway Atoll, and Tern Island. We characterized the species-and colony-specific foraging and focal distributions (represented by the 95 and 50th density contours, respectively) and quantified segregation in at-sea habitat use between species and colonies. Laysan and black-footed albatross showed consistent and significant at-sea segregation in focal areas across colonies, indicating that resource partitioning persists during post-breeding. Within breeding colonies, segregation of foraging areas between the two species was more evident for birds breeding at Tern Island. Spatial segregation decreased as the post-breeding season progressed, when spatial distributions of both species became more dispersed. In contrast to studies conducted on breeding Laysan and black-footed albatross, we found that sea surface temperature distinguished post-breeding habitats of black-footed albatrosses between colonies, with black-footed albatrosses from Midway Atoll occurring in cooler waters (3.6 degrees C cooler on average). Our results reveal marked at-sea segregation between Laysan and black-footed albatross breeding at two colonies during a critical but understudied phase in their annual cycle. The observed variation in species-environment relationships underscores the importance of sampling multiple colonies and temporal periods to more thoroughly understand the spatial distributions of pelagic seabirds.
Plan de classement
Limnologie biologique / Océanographie biologique [034]
;
Sciences du monde animal [080]
;
Etudes, transformation, conservation du milieu naturel [082]
Description Géographique
PACIFIQUE ; PACIFIQUE NORD
Localisation
Fonds IRD [F B010086731]
Identifiant IRD
fdi:010086731
