Anomalous coccolithophorid bloom over the eastern Bering Sea shelf

Anomalous coccolitophorid blooming in the eastern part of the Bering Sea occurred over an area >200 000 km(2) and lasted from early July to November 1997. Sea surface temperature in the bloom period was 2.5-3.0 degrees C above normal. Samples for phytoplankton composition were taken in the coastal zone of the Saint Paul Island (Pribilof Islands) in the first days of October. The bloom was formed by one species Emiliania huxleyi. The species numbers were as high as 2.1-2.8 min. cells/l and biomass varied from 1.1 to 1.5 mg/l. E, husleyi shares in total phytoplankton number and biomass were greater than or equal to 99.8% and greater than or equal to 99.2% respectively. According to phytoplankton data obtained in the same region in August in years with different temperature conditions (1992-1994) single cells of coccolithophorids were only found. Predominating group were diatoms which were responsible for >93% of total phytoplankton numbers and >96% ot total biomass.