Flying Squirrel LIFE

A radio tracking study of flying squirrels was carried out in the Tapiola area in 2019–2020. The study investigated the habitats and movement of flying squirrels in the urban environment. The results of the study provide more information on the behaviour of the flying squirrel in urban areas and the collected data can also be used in land use planning.

In the course of the study, ten flying squirrels were fitted with radio-tracking collars and their movements were monitored during field visits. The first collars were fitted in August 2019 and the monitoring continued until September 2020.

The tracking work was carried out by Environmental Research Yrjölä Ltd in cooperation with Luontoselvitys Metsänen Oy.

The study showed that in urban environments, flying squirrels habit relatively small areas. The current study revealed that the flying squirrel habitats were clearly smaller than those found in studies previously carried out in Matinkylä and in forests outside urban areas. In Tapiola, the average habitat of tracked females was only approximately 4 hectares in size and that of males approximately 28 hectares. A study carried out in Matinkylä in 2013 showed that the average habitat of females was 15.5 hectares and that of males 79 hectares.

Although the flying squirrel habitats were found to be small on average, the tracked group included one daredevil squirrel who moved in a more extensive area than the rest and even crossed the busy Länsiväylä highway twice. 

The main result of the study is that flying squirrels are able to live and breed in the urban environment of Greater Tapiola and that the forest patches in the area are suitable habitats for flying squirrels. However, in order to survive, flying squirrels need forests that are more similar to natural forests than parks. Furthermore, the forest patches need to be interconnected with green corridors so that the flying squirrels are able to move from one area to another.

In June 2021, the cities of Espoo, Kuopio and Jyväskylä published the guide ‘Siberian Flying Squirrel in Land Use Planning – Guide for Good Practices’. The guide includes good practices on reconciling flying squirrel conservation with land use planning. The guide is based on the cities’ first-hand experiences and is aimed in particular for the use of other cities and municipalities.

Among other things, the guide describes:

• Considering flying squirrel conservation in land use planning and implementation
• Derogation from the legal protection requirements
• Management of data related to flying squirrels

The guide provides a variety of practical examples, for example, regarding different planning solutions. The guide is aimed in particular at other municipalities and cities, but it is equally well suited for city residents, students and organisations interested in flying squirrel conservation and land use.

The guide is in Finnish but it includes a summary in English.

At the Flying squirrel LIFE project, Espoo evaluated the impact of land use planning on the flying squirrel and explored the practices that best support the protection of the flying squirrel. For the evaluation, five detailed plan areas in different stages of implementation were selected in southern Espoo. All the monitored areas have flying squirrel habitats that have been protected through plan symbols and regulations. The presence of flying squirrels and the effect of plan symbols were monitored in each detailed plan area from 2019 to 2021.

During the monitoring period, only minor land use measures were carried out in the sites, and thus the quality of the habitats was preserved. The decline in the number of flying squirrels may be due to the fluctuating population changes typical to flying squirrels. The quality of the moving routes between the habitats remained adequate, with the exception of one route that was broken as a result of wood clearance. The route had not been indicated as a flying squirrel site with a plan symbol.

The monitoring data shows that the protection of the flying squirrel can be promoted through plan symbols indicating flying squirrel sites and related plan regulations. The monitoring data suggests that if the surface area of the forest patch designated for conservation is small, the flying squirrel may not survive unless the surrounding environment remains forested. Also, routes to other forest patches in at least two directions should be protected.

The 2020 and 2021 surveys were carried out by Enviro. The 2019 survey was performed by Lumotron. The monitoring report describes the status of the flying squirrels in the spring of 2021 and evaluates the changes that took place during the monitoring period. The monitoring report has been published only in Finnish with and English summary.

Partner cities Espoo, Jyväskylä and Kuopio complied a summary on the main results and conclusions of the flying squirrel monitoring at the local detailed plan areas. The summary has been published both in Finnish and English at the website of Parks and Wildlife Finland in www.metsa.fi/en/project/flying-squirrel-life/flying-squirrel-in-urban-areas-and-commercial-forests(external link, opens in a new window).

Flying squirrels rely on connectivity to move from one area to another, for example, in search of food and nesting sites. It is therefore important to ensure that flying squirrel habitats are not isolated from one another, but there is sufficient tree coverage between them. Espoo has a long tradition of considering connectivity of flying squirrel habitats to ensure their survival in land use planning.

During the Flying squirrel LIFE project, connectivity of flying squirrel habitats was improved in three different sites during 2021–2022. In Suvisilta and Latokaskenniitty, existing flying squirrel connections were supported with planting young tree. To Finnoonlaakso, a new flying squirrel connection was created in order to enable dispersal over a wide Länsiväylä motorway. In addition to trees, the connection in Finnoonlaakso has also been supported by artificial jumping poles.

Read more from the reports:

Forest management work was carried out in an urban forest in Hyljelahti area in 2021-2022. In Hyljelahti, the City of Espoo made careful forest management that improved recreational values of the forest and protected the flying squirrel habitats. Hyljelahti area is important for the flying squirrel, and it has at least three flying squirrel core areas. At the same time, Hyljelahti is a popular and important recreational area to the people living nearby.

Forest management in Hyljelahti was made by light selection felling. Unsound trees were removed especially from the sides of recreational routes and buildings. This ensures the trees don´t cause danger to the people in the area. Also, more space was given to the natural regeneration of the new tree population. The flying squirrel also benefits from the diversification of the forest. At the cuttings, especially growth of spruce and aspen was favoured, since both species are important for the flying squirrel.

Hyljelahti forest management plan has an English summary. The plan can be found from the Finnish website.

The main coordinator of the Flying Squirrel LIFE project is Metsähallitus. The project also includes 16 partners from Finland and Estonia

In addition to work related to urban forests, the Flying Squirrel LIFE project also develops good practices for commercial forests, prepares training material for flying squirrel surveys, simulates flying squirrel habitats, compiles a national register of flying squirrel data and increases awareness and information about flying squirrels in different ways.

Further information on other project activities and partners is available on the official project website maintained by Metsähallitus(external link, opens in a new window).

With questions concerning the Flying Squirrel LIFE project, please contact

Laura Lundgren, Project Manager
+358 43 8257184
laura.lundgren@espoo.fi

Answers to frequently asked questions about flying squirrels in Espoo can be read from this page: A flying squirrel in Espoo.