About 545 endangered Saimaa ringed seals now live in Lake Saimaa, 15 more than last year, according to the latest population estimate from Metsähallitus, according to Yle.
An estimated 116 pups were born, a couple more than last year. Up to 90 percent of the observed pups were born this year in snow drifts and artificial nests. About 13 percent of the pups are estimated to have died in their nests, and Metsähallitus says the true figure is probably higher, since poor snow conditions left many pups quickly without a nest that shields them from predators.
The agency said poor nesting conditions and bycatch mortality are slowing the recovery of the Saimaa ringed seal population.
The estimate is based on the number and location of nests found in nest counts and on pup numbers. As winters grow milder, experts have had to adopt new methods. In last winter's counts, shorelines were no longer surveyed systematically, and experts mainly checked snow drifts and artificial nests.
"The method development already begun continues in a new Life project, and the goal is to move in the future to a mathematical model in which various monitoring data can be widely utilized," said Miina Auttila, a special expert at Metsähallitus, in a press release.
Bycatch mortality has multiplied in recent years. The population has grown well since the 2010s thanks to extensive and diverse conservation measures, and seals now swim in nearly every part of Lake Saimaa. "In recent years there have been several seal observations also in lakes and ponds with a water connection to Saimaa. There are also more observations from the edge areas of the distribution, which tells of seals returning to their former habitats," said Riikka Alakoski, a special expert at Metsähallitus.