Hyenas of the North: Wolverines making a comeback in southern Finland, finds study

Wolverines (Gulo gulo), the mustelid carnivores of the world’s boreal forests, are making a comeback in southern Finland after having been wiped out from there due to hunting, a new study has found.

Researchers at Aalto University in Finland combined snow track counts of wolverines with national forest inventory data based on satellite images and field measurements.

This approach allowed them to examine the influence of forest characteristics on wolverine presence on a large scale, a statement by the university said.

The wolverine was classified as endangered in Finland already in the 1980s. The species is known to have inhabited southern Finland till the 19th century after which, hunting caused its local extirpation.

“The species is returning to its historical range in southern Finland,” a statement quoted Pinja-Emilia Lämsä, a doctoral researcher at Aalto University. 

The study added that the wolverine’s survival remains threatened by its small population size, low genetic viability, and fragmented distribution.

However, the study’s use of remote sensing and field data offers vital information for safeguarding biodiversity.

For instance, the study found that wolverines tend to favour large, forested areas with deciduous trees. They also preferred areas with less dense tree cover.

“According to our research, the deciduous-dominated mixed forests typical of the south may be more important habitats for wolverines than previously thought,” Pinja-Emilia Lämsä said.

She added: “In Finland, the average forest compartment — a uniform section of forest in terms of tree species and site conditions — is relatively small. This can lead to a patchwork-like fragmentation of forest landscapes in forest management decisions. To protect wolverine habitats, mixed-species forest should be prioritised and large, continuous forest areas preserved.” 

Miina Rautiainen, a remote sensing expert at Aalto University, praised remote sensing as an excellent tool for studying the distribution of animal species across broad areas, as satellite and aerial images provide increasingly detailed information about changes in forest landscapes and their impacts on wildlife

The study, conducted in collaboration with the Natural Resources Institute Finland, was published in the journal Ecology and Evolution.