THE DIET OF THE BLUE-EYED SHAG, PHALACROCORAX-ATRICEPS-BRANSFIELDENSIS FEEDING IN THE BRANSFIELD STRAIT

The diet of the Antarctic blue-eyed shag Phalacrocorax atriceps bransf ieldensis was analysed based on the identification of the prey items i n 50 regurgitated casts collected at Duthoit Point, Nelson Island, in February 1991. Fish remains occurred in 100% of the casts and represen ted 68% by number and 90% by weight of the total prey items. From a to tal of 2112 otoliths found, 1176 fish specimens were identified belong ing to four demersal-benthic species: Harpagifer antarcticus, Notothen ia neglecta, Nototheniops nudifrons and Trematomus newnesi. Equations to estimate total length and weight from otolith length are provided. H. antarcticus and N. neglecta were the most frequent (92%) and import ant by weight (66%) respectively. Cephalopod beaks found indicate bent hic octopods as the second group in importance after fish. Other inver tebrates such as polychaetes, gastropods, bivalves and crustaceans wer e only occasional. The presence of algae and stones in the casts is at tributed to accidental ingestion. Our results are in general agreement with those published for other Antarctic localities which indicate th at P. atriceps is a benthic coastal feeder, with fish as its main food .