The species diversity was high at three of four stations int the Kattegat and Skagerrak areas and the highest at the Kattegat stations. Diatoms dominated the samples, but the individual cell numbers were relatively low or moderate. The integrated chlorophyll concentrations were within normal for this month.
The total cell numbers and the species diversity were both moderate at the Baltic Proper phytoplankton stations. The most numerous species were the small Cryptomonadales, Heterocapsa rotundata and various ciliates, but large diatoms were at places quite numerous. Aphanizomenon flosaquae were found at all stations but one, and sometimes in quite high numbers. The toxin producing Dinophysis-genus was found at the southern and western stations. The ferrybox onboard R/V Svea recorded high amounts of the cyanobacterium pigment phycoerythrin, especially at BCSIII-10. The integrated chlorophyll concentrations were low or within normal for this month.