Although Cyanobacteria are abundant in the open sea areas, in lakes, less cyanobacteria have been observed than long term average, said a press release of The Finnish Environment Institute (SYKE).

In lakes, more observations of cyanobacteria have been made this week than last week, but the amount still remains less.

Cyanobacterial blooms continue in several open sea areas and they have also been observed in many coastal sites and beaches. Several people have reported on spores of rust fungi covering lakes in the Häme region.

Spores of rust fungi that form coloured surface occurrences have been reported last week particularly in lakes in Southwestern Finland.

The arrival of the dreaded blue-green algae on Finnish shores was delayed due to cold summer but a slight warming last week coincided with sightings of algae in south-west waters.

The SYKE said that blue-green algae, which can cause an upset stomach or worse on contact with swimmers, is present on Finnish beaches once again this summer.

Blue-green algae is visible in Finnish waters across almost the whole of the western Gulf of Finland, the southern Archipelago Sea and the northern reaches of the Baltic Sea, said SYKE.