Affiliation:
1. Department of Biology, Wake Forest University, Winston-Salem, NC 27109-7325, USA.
2. Environment Canada, 11 Innovation Boulevard, Saskatoon, SK S7N 3H5, Canada.
Abstract
Waved albatrosses ( Phoebastria irrorata Salvin, 1883) forage close to their breeding grounds on Isla Española, Galápagos, during the short chick-brooding stage and make long trips to the Peruvian upwelling during incubation and chick rearing. Previous studies have suggested foraging segregation by sex: females spend more time searching than males do while foraging in the Galápagos Marine Reserve (GMR), and band recoveries suggest higher bycatch vulnerability of males in the Peruvian upwelling. We used stable isotope analysis (δ15N and δ13C) of whole blood of adult male and female albatrosses to test for intraspecific foraging segregation in this sexually dimorphic species. Analysis of serial blood samples revealed higher δ15N values in males, suggesting consumption of prey items of higher trophic level. We also detected seasonal variation in foraging ecology, with higher δ15N values at the beginning of the breeding season. Sex and regional differences in δ13C values were not significant, reflecting primarily pelagic foraging sites of both sexes, both in the GMR and the Peruvian upwelling. Our results provide evidence of trophic segregation, suggestive of competitive exclusion, and novel information on marine isoscape values in the Eastern Equatorial Pacific.
Publisher
Canadian Science Publishing
Subject
Animal Science and Zoology,Ecology, Evolution, Behavior and Systematics
Reference67 articles.
1. Anderson, D.J., Schwandt, A.J., and Douglas, H.D. 1998. Foraging ranges of waved albatrosses in the eastern tropical Pacific Ocean. In Albatross biology and conservation. Edited by G. Robertson and R. Gales. Surrey Beatty and Sons, Chipping Norton, Australia. pp. 180–185.
2. At-sea distribution of waved albatrosses and the Galápagos Marine Reserve
3. Awkerman, J.A. 2006. Foraging ecology and population demography of waved albatrosses (Phoebastria irrorata). Ph.D. thesis, Wake Forest University, Winston-Salem, N.C.
4. Foraging activity and submesoscale habitat use of waved albatrosses Phoebastria irrorata during chick-brooding period
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