FINLAND’S vast forests are not as healthy as a casual observer might believe. A comprehensive survey of threatened species has determined forests are the habitat of the greatest number of at-risk species.

The Finnish Environment Institute SYKE has estimated that Finland is home to 2,247 threatened species. Forests are the habitat with the largest number, 814, followed by agricultural environments with 401 and shorelines with 290. The Baltic Sea, which is often in the news for environmental problems, is home to only 17 threatened species.

Endangered forests

In the report, Pertti Rassi, Esko Hyvärinen, Aino Juslén and Ilpo Mannerkoski say there are several distinct reasons why forest species are at risk.

“In the current evaluation, causes of threat related to forests are divided into five groups: forest management activities, changes in the tree species composition, reduction of old-growth forests, decreasing amounts of decaying wood and reduction of burnt forest areas.”

Selected species at risk • The flower Viola collina, often known as a violet, is listed as Vulnerable. • The mountain hare is classified as Near Threatened. • The famous Saimaa ringed seal is Critically Endangered. • The lesser white-fronted goose is Critically Endangered. • The wolf is Endangered. Regionally Extinct species • 332 species are classified as Regionally Extinct in Finland. • 59 species’ extinction is blamed on changes in the forest environment. • 50 species went extinct due to the overgrowth of open habitats, such as meadows. • 42 species have chemical disturbances such as eutrophication as a primary or secondary cause for extinction. • Climate change has caused only one extinction, Arctoa hyperborea, a type of moss.

Finland is the most forested nation in Europe. Over 70 per cent of Finland’s land area is covered by forest, which equates to about 230,000 square kilometres. Yet it is not in the best of health.

“The amount of decaying wood has been found to be one of the most important factors affecting the diversity of forest species, and special attention has been paid to it recently,” the authors continue. “On average, Finnish forests contain 5.4 cubic metres per hectare of dead wood, which is very little in comparison to old-growth forests in their natural state, where the amount of decaying wood is 20-120 cubic metres per hectare.”

Perversely, the authors point out the attempt to use logging residue and stumps for biofuel, which was supposed to be good for the environment, is in fact decreasing the amount of decaying wood in trees and putting species at risk. The lack of decaying wood is particularly hard on species that depend upon it, such as fungi.

“One cannot be very optimistic about developments in the coming 10-year period. For example, it has not been possible to mitigate climate change substantially. New clouds are gathering in the sky. Finland plans to cover a larger proportion of its energy demand with wood in the future. In practice, this will mean that all logging residue will be collected from forests. The planned consumption of energy wood will decrease the amount of decaying wood in forests significantly and may cause drastic changes in our forest flora and fauna.”

Saimaa seal

While forests contain the largest number of threatened species, the rate of decline has slowed. Other habitats, particularly in mires, shores and rock outcrops, contain more at-risk species than previously thought. Some organisms in aquatic locales are also threatened.

The Saimaa ringed seal, the poster boy of Finnish endangered species, is continuing to experience difficulties. The seal showed slow but steady improvement until 2005, when the population began to decline. The State Forest Management agency Metsähallitus estimates only 300 individuals survive.

“The clearest reasons for this were mild winters, during which the proportion of pups found dead in their lairs increased from 8 per cent to 30 per cent, as well as drowning caused by fishing tackle,” the authors explain.

DAVID J. CORD

HELSINKI TIMES

LEHTIKUVA / JUSSI NUKARI