Geographical variation in the diet of the Antarctic fur seal Arctocephalus gazella

CASAUX RICARDO; BARONI ANDREA; ARRIGHETTI F.; RAMÓN ANALÍA; CARLINI ALEJANDRO

POLAR BIOLOGY

Año: 2003 vol. 26 p. 753 - 758

0722-4060

Abstract The diet of non-breeding male Antarctic fur seals Arctocephalus gazella was investigated at different localities of the Antarctic Peninsula (Cierva Point and Hope Bay), South Shetland Islands (Deception Island and Potter Peninsula) and South Orkney Islands (Laurie Island), by the analysis of 438 scats collected from January to March 2000. The composition of the diet was diverse and both, pelagic and benthic-demersal preys were represented in the samples. The Antarctic krill Euphausia superba was the most frequent (except at Cierva Point) and numerous preyat all the study sites, being followed by fish, penguins and cephalopods. The Antarctic krill also predominated by mass being followed by fish or penguins. Fish were the second most important prey by mass at the Antarctic Peninsula whereas penguins were second most important prey by mass at the South Shetland and South Orkney islands. Among fish, Pleuragramma antarcticum was the species that most contributed to the diet of the Antarctic fur seals at the Antarctic Peninsula whereas Gymnoscopelus nicholsi predominated at the South Shetland and South Orkney islands. The results are compared with previous studies and the possibility of implement monitoring studies on the distribution/abundance of Myctophids and P. antarcticum based in the analysis of the diet of the Antarctic fur seal is considered.