In winter 2016, artificial snowdrifts were built for the third consecutive year to improve the nesting conditions of Saimaa ringed seals in poor snow conditions. The seals’ breeding success depends entirely on the snow and ice cover, because they make nests in snowdrifts piled on lake ice by the shore. The nest protects the pup from the cold and predators, while offering the mother a peaceful site for nursing her offspring.
In mild winters, the snowdrifts are insufficient for nesting by seals. The innovative technique, developed by the University of Eastern Finland, of providing man-made snow mounds is vital to protecting the Saimaa ringed seal population.
In January 2016, snow conditions on Lake Saimaa varied, with moderate snowdrifts on the shores of islands and islets in wide open water areas, but none in small-scale water areas. Of the total of 174 people participating in making the snow mounds, 147 were volunteers. All in all, 211 snowdrifts were made in different parts of Lake Saimaa, and the work was completed in a matter of two weeks.
Metsähallitus coordinated the efforts and contribution of the University of Eastern Finland and WWF Finland played a key role – alongside the staff of local Centres for Economic Development, Transport and the Environment – by participating in building the artificial snowdrifts.
According to a nest census carried out in the spring, approximately half of the 86 seal pups observed were born in nests in artificial snow mounds, and their mortality rate remained as low as in winters with good snow conditions. The man-made snowdrifts are an effective method of improving the survival rate of Saimaa ringed seal pups. An excellent network of locals forms an essential part of the related practical work.
Photo: Mervi Kunnasranta, UEF