The absence of krill from the South Georgia zone, winter 1983

An extremely low abundance of the Antarctic krill, Euphausia superba, was observed in the Scotia Sea during the austral winter of 1983. The decline could not be attributed to any of the environmental factors investigated, including phytoplankton biomass which was higher than expected. One effect of the reduced krill population, observed during the 1983 to 1984 summer, was a much lower than average breeding success for bird and seal predators of krill on Bird Island, South Georgia. Historical evidence suggests that drastic reductions in krill abundance may not be uncommon, and will have profound consequences for the developing krill fishery.

Details