(Arvicola terrestris)
Biology:
The large vole or shear mouse occurs in aquatic and terrestrial forms and can move by running, swimming and diving. The terrestrial form creates extensive burrow systems and raises heaps of earth. The animals have a plump body of 12 to 22 cm in length with a stocky, large head and ears hidden in the fur. The tail is relatively short at about half the body length. The fur is gray-brown to brown-black on the upper side and becomes lighter towards the bottom. Females have 2 to 4 litters with an average of 4 young per year. The diet consists mainly of succulent plant food; aquatic water voles search for their food outside the tunnel system in the water and on the shore (e.g. aquatic plants). They also use the roots that constantly grow back into the tunnel system. On agricultural and horticultural sites, they mainly feed on underground storage organs of vegetable and ornamental plants as well as the roots of various trees and shrubs.
Plant parts with a low water content, e.g. seeds, are hardly accepted.
Damage:
Damage caused by water voles occurs on cereals, vegetables, in tree nurseries, in orchards and in forests. Of great importance is the feeding on roots, tubers and bulbs. In forests and orchards, feeding on the roots of young trees can cause particularly severe damage.
