Feeding Behaviour of Eurasian Beavers (Castor fiber) Along Small Streams in an Agricultural Landscape

Abstract

In areas with high population density, the Eurasian beaver may be forced to utilise sparsely forested landscapes where living conditions may not be optimal for the species. Here, we examine the feeding strategy of Eurasian beavers along a number of small (mainly) forested streams in the Czech agricultural landscape. Diet availability in these sparsely forested landscapes is characterised by a lack of woody plants but a large supply of herbaceous vegetation, including agricultural crops grown close to the watercourse. The beaver has adapted to such conditions by building dams on low-water streams, allowing it to move between scattered diet resources. In winter, the main dietary component was woody plants (70% V), with species normally neglected in optimal sites (e.g. Acer negundo, Prunus spp.) taken in the absence of more favoured species (e.g. Salix spp., Populus spp.), the remaining 30%V consisting of herbaceous vegetation. In summer, however, the main component in the diet was herbaceous vegetation (90% F), which included agricultural crops (56% V). Where there were not enough trees, the beaver tended to leave its summer territory and move to stretches with denser tree stands. Thus, beavers in sparsely forested agricultural landscapes have adapted by utilising the diverse supply of herbaceous vegetation, though its continued presence in the landscape is still primarily dependent on sufficient stocks of woody plants, which the beaver needs to survive winter.