The Water Vole (Arvicola terrestris)

There are two species of water vole in Europe, the larger southern water vole, which lives in western France, Spain and Portugal, and the northern water vole, which lives in Britain, North eastern France and the rest of Europe west of a north/south dividing line connecting Belgium and Italy, and in a broad swathe stretching to north-west China including Israel and Siberia.

The northern water vole is then generally divided into two main subspecies – Britain’s Arvicola terrestris amphibious, and the smaller continental Arvicola terrestris sherman. The British water vole is usually associated with water and does very little damage apart from where its burrowing may cause a riverbank to collapse, whereas its continental cousin is far ranging and is considered an agricultural pest across much of Europe.

The water vole, or water rat as it is sometimes called, came to prominence as Ratty, one of the main characters in the classic children’s book ‘The Wind in the Willows’. It can be most easily distinguished from the brown rat by having a shorter, less scaly tail and a blunter muzzle. One of the most evocative sounds of a summer evening’s walk along a riverbank was a loud ‘plop’ as a water vole made itself scarce by diving into the water. This also served as a warning to other water voles that there was an intruder about. Other water vole fieldsigns are their feeding stations and latrines. Their burrows no longer indicate the presence of water voles as many of them are now empty due to predation by mink.

Water voles live in burrows in river banks. They range in colour from medium to dark brown with black voles most common in Scotland. They are herbivorous and feed on over 200 different types of reeds, grasses, rushes, herbs, shrubs and trees. At approximately 300 gram, the water vole is the largest British vole.

Breeding lasts from March to October, with a female producing anything from two to five litters with each litter containing between three and eight young. Water voles do not hibernate and store food in their burrows for winter use. Water voles rarely live to three years.

“Over the last 15 years or so, the water vole has undergone one of the most catastrophic declines of a species ever known in the U.K. – a far more rapid decline than that suffered by the charismatic mega fauna of Africa or Asia – and it has happened here right under our noses.”

Alastair Driver, Chair, U.K. Water Vole Steering Group