ABSTRACT
The common vole in Europe is a widely spread pest of crops and grasslands. Outbreak zones in Europe usually represent large, open, monotonous and uniform bio-topes. Catches are usually only a measure of the activity of the voles on the surface and are influenced by the number of animals per area, climatic conditions, and by the phase the population is in. The percentage of emigrating voles rises continually towards the end of a cycle. The sex-ratio changes to the disadvantage of the males in peak years. Each winter the populations are diminished by up to 60% or more; in spring they suffer a crisis in which the older voles die and reproduction is low. When using traps consider that: voles to varying degrees live in a small area, voles usually keep to their runways, and voles are active day and night. Mark the traps by colored sticks reaching above the vegetation level.
