Diet of Adélie penguinsPygoscelis adeliaeduring the post-hatching period at Esperanza Bay, Antarctica, 1987/88

摘要

The diet of the Adélie penguinPygoscelis adeliaewas studied at Esperanza Bay, Antarctic Peninsula, during the post-hatching period by quantitative analysis of adult stomach contents. Euphausiids constituted on average 96 by mass, while fish contributed 4 by mass. Amphipods were present in small amounts. Antarctic krillEuphausia superbawas the predominant component throughout the sampling period. In contrast,Euphausia crystallorophiasoccurred rarely. Differences in the size of krill taken by Adélie penguins appear to reflect either local changes in the availability of certain age classes at various times in the breed ing season, or differences in foraging areas, or are due to year-to-year differences in prey availability and abundance, possibly caused by variations in seasonal ice cover.Pleuragramma antarcticumconstituted the bulk of the fish portion, particularly during the guard perio