Levels of toxic blue-green algae, or cyanobacteria in the Archipelago Sea have already become catastrophic in places, according to resident nature photographer Jaakko Ruola.
"I've never experienced a summer like this before," said Ruola, who six years ago co-founded the Operation Unique Archipelago Sea campaign.
Since then, he has been working hard to get decision-makers and the public interested in the ecological state of the fragile Archipelago Sea.
"As a child, I myself got to experience the clear waters, catching fish and abundant seaweed. I would love for my grandchildren and future generations to experience the same joys," Ruola told Yle.
High levels this summer
This summer, Emilia Pohto, a university trainee at the Ely Centre for Southwest Finland, has been monitoring blue-green algae in southwest Finland. According to her, there have been several sightings of blue-green algae on the Järvi-Meri Wiki website in the last few days.
"Blue-green algae is very abundant and in many places it is especially abundant," Pohto said.
The Ely Centre's current assessment is based on observations from standard monitoring points and from the public. The number of blue-green algae blooms always depends on local conditions:
"Huge surface patches are less likely to form where there is more water flow. If the water is stagnant, for example in a bay or cove, that's where the bacterial blooms are more likely to appear," Pohto said.
Vivi Fleming, Specialist Scientist and Head of the Changing Baltic Group at the Finnish Environment Institute (Syke), told Yle that blue-green algae may have increased slightly during the past week, at least in the western Gulf of Finland.
Comprehensive satellite images are not available due to cloud cover, and changes have also been visible in the Gulf of Bothnian over the past few days. Several years of monitoring have shown an increase in blooms in the Gulf of Bothnia.
"Over the past decade, the previously sporadic blue-green algae rafts in the Gulf of Bothnia seem to have become an everyday occurrence," Fleming said.
According to Syke, children and pets must not be allowed into contaminated water, and adults should also avoid swimming. The institute has advised that children or pets suspected of having been exposed to contaminated water should be thoroughly washed with clean water.
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