The phytoplankton community in the Skagerrak and the Kattegat was dominated by a small coccolithophore, Emiliania huxleyi, and a diatom, Pseudo-nitzschia spp. The potentially harmfull naked dinoflagellates Karenia
mikimotoi and Karlodinium veneficum were common and particularly at Släggö. The integrated (0-10 m) chlorophyll a concentrations were normal for this month. The Baltic Sea was mainly dominated by colonies of small cyanobacteria and other small unicells. Large diatoms were common in the Eastern and Southern part of the Baltic Sea. The integrated (0-10 m) chlorophyll a concentrations were normal for this month with an exception of Kalmar Sound, where the concentration was higher than normal for this time of the year.