Observations of multispecies seabird flocks around South Georgia

We observed 195 multispecies feeding flocks of birds near Bird Island, South Georgia, between 4 February and 5 March in 1986. Up to 19 seabird species plus Antarctic fur seals (Arctocephalus gazella) were involved. Black-browed Albatross (Diomedea melanophris), Macaroni Penguins (Eudyptes chrysolophus), and prions (Pachyptila spp.) were the most abundant species. Most flocks were in the vicinity of a large inshore patch of Antarctic krill (Euphausia superba), and most observed feeding was by Black-browed Albatross, which appeared to initiate and dominate the flocks. Short feeding bouts by surface-feeding species appeared to be coupled with the surfacing of penguins and seals. We conclude that foraging penguins and seals caused prey to approach the surface where near-surface foraging species could feed.