The behaviour of mature and immature male bank voles (Clethrionomys glareolus)

Neutral-arena encounters were staged between pairs of sexually mature male bank voles (Clethrionomys glareolus), between pairs of immature males, and between pairs consisting of one of each. Mature males exhibited more aggressive components of behaviour to each other than did immature males, but mature males did not attack immature males in ‘mixed’ encounters. The relevance of these results to the population ecology of voles is discussed.