Title
Shared dietary niche between sexes in Magellanic Penguins
Author(s)
Castillo, J.;Yorio, P.;Gatto, A.
Published
2019
Publisher
Austral Ecology
Abstract
Prey use by male and female Magellanic Penguins (Spheniscus magellanicus) was quantified during chick rearing in northern Golfo San Jorge, Argentina and the dietary niches and diet composition of each sex were assessed and compared. A total of 67 males and 45 females were flushed during the chick stages of 2011 and 2012. Argentine Anchovy (Engraulis anchoita) was the main prey in terms of importance by mass in males and females in all stages and years (52.4-86.6% and 83.8-88.7%, respectively), except during the old chick stage in 2011 when the main prey in males and females was the Shortfin Squid (Illex argentinus) (63.1% and 44.4%, respectively). Analyses of similarity showed that diet composition in terms of contribution by mass of the main prey species was similar between sexes. Based on the isotopic values of delta C-13 and delta N-15 corresponding to 38 males and 21 females, the Bayesian mixing model outputs showed that Argentine Anchovy was also the main prey. In both years and chick stages, the isotopic niche of males and females was similar. The similarity in the dietary niche between male and female Magellanic Penguins raising chicks may be due to the high availability of Argentine Anchovy during the study period and the consequent dominance of this forage species in the diet of both sexes.
Keywords
Argentine Anchovy;diet composition;sexual differences;Spheniscus;magellanicus;stable isotopes;phalacrocorax-carbo-sinensis;stable-isotope analysis;spheniscus-magellanicus;foraging behavior;sexual segregation;diving;behavior;provisioning behavior;mixing models;body-size;patagonia;Environmental Sciences & Ecology
Access Full Text
A full-text copy of this article may be available. Please email the WCS Library to request.
![]()
Back
PUB24827