How Do the Beaver Home Ranges Vary during the Range Expansion?

Reoccupation of European landscapes by native species causes changes in their population densities and home ranges. To test whether an increase in population density affects home range sizes, we studied the strictly territorial herbivore Eurasian beaver (Castor fiber). Twenty-four beavers were radio-tracked to reveal their home ranges under varying population densities. The mean length of occupied shorelines was 2648.0 ± 1530.6 m. We did not find any linkage between home range sizes and population densities. Our results showed that the availability of resources was significantly associated with the duration of site occupation. Thus, the space use was primarily determined by the availability of food resources, rather than by rising population density.