Habitat and nest use during natal dispersal of the urban red squirrel (Sciurus vulgaris)

As urban environments differ from the natural environment, the ability of a species to move in and use variable land composition types determines its fate in the urban environment. In many mammalian species, the selection of home ranges mainly occurs during natal dispersal. Thus, habitat selection of juvenile individuals greatly determines where animals are found in the city. Here, our goal is to understand how an originally forest-dwelling rodent selects components of an urban habitat. We used radio telemetry to record the habitat and nest use of Eurasian red squirrels (Sciurus vulgaris) in the city of Turku in southwestern Finland, with the main focus on habitat use during natal dispersal. We found that although the red squirrels preferred areas with more trees available than in the surrounding urban landscape they nevertheless often used sites with only a few trees. This result was highlighted by the analysis of the home range scale, as the area used did not differ greatly from the habitat composition of the available landscape. Juvenile red squirrels used the deciduous land cover type more often during movements in the natal area than during dispersal and explorative movements; however, they also settled in areas with less deciduous land cover type than in the natal area. Our results show that in urban areas movements of red squirrels are not restricted to their natural habitat type, which is a coniferous forest, but that they seem to be well adapted to urban areas, being able to utilize urban structures.