Interannual variation in the autumn diet of the gentoo penguin Pygoscelis papua at Laurie Island, Antarctica

The diet of the gentoo penguin Pygoscelis papua was investigated during three different autumn periods at Laurie Island, South Orkney Islands (60°46’S, 44º42’W), Antarctica. Stomach contents of migrant adults were sampled during 1993, 1995 and 1996. Fish were the most important prey by mass in 1995 (81.1%) and 1996 (60.5%) whereas crustaceans predominated in 1993 (70% by mass). Euphausia superba was largely the most important prey among the eleven crustacean taxa identified in the samples. Among fish, species of the family Nototheniidae predominated in the diet with G. gibberifrons as the most important prey by mass in 1993 and 1995 and N. nybelini in 1996. Other nototheniid fish such as L. nudifrons and T. newnesi were also well represented in the three sampling periods. A total of 1628 squid lower beaks were found and 1582 (97%) of them were identified as Psychroteuthis glacialis. Diet composition in terms of frequency of occurrence, mass and number is compared with results of previous studies.