Acoustic estimates of krill density at South Georgia during 11 austral summers between 1981 and 1998

Acoustic estimates of densities of Antarctic krill, Euphausia superba, at South Georgia are presented for eleven austral summers between 1981 and 1998. Krill abundance at the island fluctuated widely from year to year over this time, ranging from ?2 to ?150 gm-2 (wet weight). The 1982, 199 1 and 1994 austral summer seasons were characterised by particularly low abundances of krill. For five of the summers between 1990 and 1998 it was possible to calculate separate density estimates for north-eastern and north-western ends of South Georgia. In four of these years density was higher to the east.