The diets of five summer breeding seabirds in Ad�lie Land, Antarctica

Abstract

The diets of five breeding seabird species were investigated on Adelie Land in January–February 1982. Stomach contents of Adelie penguins, Pygoscelis adeliae, were sampled by a water off-loading method and of Procellariiformes by spontaneous regurgitation. Diet compositions by mass were: Adelie penguin (79% euphausiid, 18% fish, 3% squid); Cape pigeon, Daption capense, (64% euphausiid, 29% fish, 7% carrion); Antarctic fulmar, Fulmarus glacialoides, (64% euphausiid, 20% carrion, 16% fish); snow petrel, Pagodroma nivea, (95% fish, 2% euphausiid, 1% carrion) and Wilson's stormpetrel, Oceanites oceanicus, (39% fish, 37% euphausiid, 13% carrion, 12% various crustaceans). The present Adelie penguin diet is consistent with those reported in other studies, given our knowledge of geographical variation in food availability. Differences in the diets of fulmarine petrels appear to relate to differences in foraging areas. The snow petrel is a fish-eating bird associated with pack-ice. Cape pigeon and Antarctic fulmar are mainly krill-eaters and we infer segregation along a neritic/oceanic gradient because of the importance of the neritic Euphausia crystallorophias in the former and the oceanic E. superba in the latter.