Benthic feeding by krill, Euphausia superba Dana, in coastal waters off West Antarctica and in Admiralty Bay, South Shetland Islands

Abstract

Diatoms in the food of krill caught in the summer in coastal waters close to the South Shetland Islands and in the summer and three winters in Admiralty Bay, King George Island were investigated. The diatoms were used as indicators of sources of krill food. Principal component analysis divided the diatom taxa into two groups, one being pelagic diatoms and from the food of krill in coastal waters, and the other being benthic diatoms and taxa from the food of krill in Admiralty Bay. All pelagic taxa of diatoms were consumed by krill. In the summer in coastal waters, benthic diatoms in krill food originated from the sublittoral. In the summer in Admiralty Bay, besides phytoplankton, diatoms were noted from the sublittoral and littoral in the food of krill. However, in the winter mostly sublittoral and epiphytic diatoms were present in krill food.