CEPHALOPODS EATEN BY WANDERING ALBATROSSES (DIOMEDEA-EXULANS L) BREEDING AT 6 CIRCUMPOLAR LOCALITIES

The beaks of 9,994 cephalopods of 61 species, obtained mainly from chi ck regurgitations of wandering albatrosses (Diomedea exulans L.) at Go ugh, Auckland, Antipodes, Prince Edward and Macquarie Islands and Sout h Georgia, were used to specify and calculate the biomass of cephalopo ds consumed. Histioteuthidae were most important by numbers and biomas s at Gough Island (in warmest seas), but Onychoteuthidae increasingly superseded them southwards; Kondakovia longimana formed 59 to 75% of b iomass eaten at the three localities nearest the Antarctic Polar Front . Other important families were Octopoteuthidae, Cranchiidae, Architeu thidae (juveniles) and Ommastrephidae (South Georgia only). Most frequ ently eaten were Histioteuthis atlantica 13.7%, Galiteuthis glacialis 12.4%, H. eltaninae 12.0% and Kondakovia longimana 11.6%. Wandering al batrosses rearing chicks can forage at least to 3,000 km in a single f oray, and may exploit an important food source about 1200 km from the nest (as in the probable commensalism of South Georgian birds with the Falkland Islands fishery). They feed, sometimes opportunistically, on cephalopods active or moribund at the surface, or discarded or lost b y trawlers, cetaceans or seals. Vertically migrating cephalopods, espe cially bioluminescent species, are disproportionately frequent in thei r non-commensal diet, suggesting that they often feed at night.