A case of mass occurrence of Prorocentrum minimum in the Kiel Fjord

Abstract

A case of mass development of the potentially toxic dinoflagellate horocentrum minimum was recorded in the inner reaches of the Kiel Fjord in July/August 1983. Although this species has been sporadically recorded at a number of locations in Norwegian, Danish and Swedish coastal waters, this is the first record of a massive bloom in this part of the Baltic Sea. The bloom seems to have been favoured by relatively high temperatures, high insolation and calm weather conditions preva~ling at the time. The dinoflagellate did not prove toxic either to mussel beds in adjoining areas of the Kiel Bight, affected by the bloom, or to other test organisms in the laboratory.