Differences in diet composition and foraging patterns between sexes of the Magellanic penguin (Spheniscus magellanicus) during the non-breeding period as revealed by δ13C and δ15N values in feathers and bone

@article{Silva2014DifferencesID,
  title={Differences in diet composition and foraging patterns between sexes of the Magellanic penguin (Spheniscus magellanicus) during the non-breeding period as revealed by $\delta$13C and $\delta$15N values in feathers and bone},
  author={L. Silva and F. Saporit and Dami{\'a}n G. Vales and Maur{\'i}cio Tavares and Patricia Gandini and Enrique Alberto Crespo and Luis Cardona},
  journal={Marine Biology},
  year={2014},
  volume={161},
  pages={1195-1206}
}
Abstract In diving seabirds, sexual dimorphism in size often results in sex-related differences of foraging patterns. Previous research on Magellanic penguins, conducted during the breeding season, failed to reveal consistent differences between the sexes on foraging behavior, despite sexual dimorphism. In this paper, we tested the hypothesis that male and female Magellanic penguins differ in diet and foraging patterns during the non-breeding period when the constraints imposed by chick rearing… 
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TLDR
The authors study the variability of blood parameters by sex, age class, and year of beached Magellanic Penguin during the nonreproductive period in northern Argentina to call for a better knowledge of the health status of the species along its annual cycle.
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