The importance of fish in the diet of the south polar skua Catharacta maccormicki at the South Shetland Islands, Antarctica

Twenty eight stomach contents of the South Polar Skua Catharacta maccormicki were collected throughout the breeding season at Half-moon Island, South Shetland Islands, Antarctica. The analysis of the samples indicated that fish were the most frequent prey (100%) and also predominated in mass (98%) and that their importance remained constant all along the study period. Eight fish species were identified (Electrona antarctica, Pleuragramma antarcticum, Krefftichthys anderssoni, Champsocephalus aceratus, Gymnoscopelus braueri, Electrona carlsbergi, Protomyctophum normani and Protomyctophum tenisoni) being E. antarctica the most important prey. The unexpected fish importance in the diet composition as well as its implication for CCAMLR are commented.