Summary
The phytoplankton diversity and the total cell numbers were relatively high at most stations along the Swedish west coast. The only exception was Å17 where total cell numbers were low. Diatoms dominated overall in cell numbers and Pseudosolenia calcar-avis was common in the Kattegat. The coccolithophore Emiliania huxleyi was found in relatively high cell numbers at all stations. The integrated chlorophyll concentrations (0-10m and 0-20 m) were low, but within normal for this month at all stations except at Å17 where it was a bit elevated in the integrated sample (0-20 m). Diversity and cell abundance of phytoplankton were generally moderate in the Baltic Sea, with mostly Chaetoceros danicus, Gymnodiniales, Cryptomonadales, the colony-forming cyanobacterium Snowella sp. and various ciliates. At the stations in the southern parts of the Baltic Sea; BY2, BY5, Hanö bight and BCIII-10, filamentous
cyanobacteria were present. Of potentially toxin-producing species there were only a few cells at various stations in the Baltic Sea. The integrated chlorophyll concentrations (0-10m and 0-20 m) were within the normal range for this month at all stations except at REFM1V1 where the concentration was higher than normal from 0-10 meters.