Distribution of krill (Euphausia superba Dana) catches in the South Shetlands and South Orkneys

Zones of 20 km width are defined around selected colonies of penguins distributed around the coasts of the South Shetland and South Orkney Islands. Krill catches in these zones are shown to have a consistent pattern in Subarea 48.1 but an unpredictable distribution in Subarea 48.2, probably as a result of more variable hydrographic conditions. About 50% of the catch in Subarea 48.1 from December to March was taken within 40 km of the coast, and 90% within 80 km in all years 1988-1990. In 1987 and 1988 75% of the catch in Subarea 48.2 between December and March was taken within 80 km of colonies in the South Orkneys. Estimates of consumption rates, foraging ranges and population sizes from the literature are used to show that for some years, at distances of between 20 and 60 km from predator colonies catches in January and February may be up to 48% of the land-based predator consumption. Whilst the overall ratio of catch to consumption is relatively low (27%), any competition between the fishery and predators as a result of large increases in catch is likely to emerge in these areas earlier than would be expected considering the fishery as a whole.