General Description
The dataset describes the occurrence of flying squirrels in the Turku area. The flying squirrel is a species listed in Annex IV of the EU Habitats Directive, requiring strict protection. Disturbing, killing, destroying nesting sites, and commercial use of the species are prohibited. Additionally, the destruction and degradation of breeding and resting places are forbidden without an exemption permit.
The City of Turku investigates the presence of flying squirrels and suitable habitats within its municipal area. The survey covers the entire mainland area of Turku, excluding islands where flying squirrels are not currently known to occur. The city is divided into four sub-areas, each surveyed annually. The report describes the flying squirrel situation and the distribution of suitable habitats in the survey year.
Survey Objectives
The aim of the survey is to identify areas important for the long-term success of the flying squirrel, regardless of whether the area is inhabited at the time of the survey. In the field, areas with trees over six meters tall were examined, excluding rocky pine forests. The survey does not replace more detailed studies, such as those conducted during zoning processes.
Data Quality
The reliability, timeliness, and accuracy of the dataset are good. The data is maintained by Turku City's environmental protection department and updated annually. The source is the surveys conducted so far by Envibio Oy.
Habitat Classifications
-
Core Areas
Areas where flying squirrels spend most of their time, breed, and rest. These are often spruce-dominated and contain hollow aspens, nest structures, and food trees. Core areas may be inhabited or vacant at the time of the survey, and their preservation is important.
-
Potential Core Areas
Forest patches suitable for flying squirrels but with no observations. These are important for the species' long-term survival.
-
Habitats
Areas near core areas where flying squirrels move and forage. These may also include developing habitats.
-
Corridors
Tree connections between core areas and habitats. Weak points are defined by canopy gaps and classified by the severity of the barrier effect.