Siberian flying squirrels are elusive, but there has long been evidence of a significant population just west of Helsinki in the sprawling municipality of Espoo – particularly in Nuuksio National Park.
In rapidly-growing Espoo, the creatures have long been the bane of real estate developers. They are forbidden to build in any areas where there is evidence of a flying squirrel community – most often in the form of tiny rice-like droppings.
If they build nearby, they are asked to leave natural green corridors connecting population groups. However this is only a recommendation, not a law.
Within the EU, Siberian flying squirrels are only found in the Baltic states and Finland, where they are classified as threatened and vulnerable – one notch above endangered.
The latest study found 12 flying squirrel habitats in Helsinki, six in Keskuspuisto (Central Park) and six to the west of it. The area researched covers about a quarter of the entire city area. Environmental Inspector Raimo Pakarinen of the Helsinki Environment Centre says it is also possible that the species has or may spread to eastern Helsinki as well.
The last confirmed permanent populations of flying squirrels in Helsinki were recorded in the 1930s. Since then there have only been scattered sightings. Pakarinen says their return is an indication of the biodiversity of the city’s recreational forest areas. The animals require a mixed forest including vegetation and trees of varying ages.
The study suggests that the past winter, which was relatively short and mild, was favourable for the species. The lack of snow cover also made it easier for researchers to detect their scat. The presence of the shy creatures is very difficult to ascertain otherwise.
