Polar Biology

, Volume 16, Issue 1, pp 75–77 | Cite as

Sexual differences in the diet of king cormorants at Macquarie Island

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Abstract

Sexual differences in the diet of king cormorants,Phalacrocorax albiventer, were investigated during the 1993/1994 austral summer at Macquarie Island. The major food items, identified by otoliths in regurgitations, were demersal fish; fish mass consumed could be estimated using a wet mass-otolith length relationship. Two fish species,Paranotothenia magellanica andHarpagifer georgianus, constituted 98% of the wet mass (male and female cormorants combined). Estimated individual fish mass ofParanotothenia magellanica (19.6±11.6 g) was greater than that ofH. georgianus (2.8±1.3 g). Total wet mass of food and number of fish in regurgitations did not differ statistically between the sexes of cormorants. However, males tended to feed on larger fish than did females.

Keywords

Sexual Difference Fish Species Food Item Major Food Large Fish 

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Copyright information

© Springer-Verlag 1996

Authors and Affiliations

  1. 1.National Insitute of Polar ResearchTokyoJapan
  2. 2.Department of Biology, Faculty of ScienceOsaka City UniversityOsakaJapan

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