Description: A small reddish-brown mammal with grey/cream underbelly. It has a tail that is half the length of its body, shorter than the wood mouse but longer than that of the field vole. It also has smaller eyes and ears than the wood mouse and a more rounded snout.
Size: 8-12 cm in length (tail 4-6 cm).
Weight: Approximately 15-40 g.
Lifespan: Average lifespan is around 6-18 months.
Breeding: Breeds mainly during the spring and summer, 3-4 litters of 3-5 young. Lives in shallow burrows or may build grassy nests above ground. Young become sexually mature at 6-8 weeks.
Habitat: Lives in woodland, hedgerows, parks and gardens, anywhere there is suitable ground cover and available food
Diet: Mainly seeds, nuts, fruit and other plant material, small insects.
General ecology: Plentiful all year round as does not hibernate. An important food source for owls and other birds of prey, also for foxes and other predators.
Distribution and main sites: Bank voles are one of the most common small mammals and can be found throughout mainland Britain.Not commonly found on outlying islands or in Northern Ireland, however. Distribution on the above map mainly reflects local surveys but these resourceful animals may also be seen in gardens as they will visit bird feeders.
Local survey history: Surveys are regularly carried out in various locations, including Whitchurch, Shrewsbury, Preston Montford, Ironbridge, Wenlock Edge, often by, or on behalf of, organisations such as Shropshire Mammal Group, National Trust, Shropshire Wildlife Trust, Ironbridge Meadows Group. Generally under-recorded.
Conservation status: Common in Shropshire and throughout most of mainland Britain. Categorised as of ”least concern” in the IUCN Red List.
Threats: Main threats are changes in land use, loss of hedgerows, woodland and green corridors. Pesticides, herbicides, etc. are also a threat.
Main recording methods: Live sightings are quite frequent as the animals are active both day and night. Small mammal surveys are carried out using humane traps (Longworth and/or BioEcoSS tube traps) to record the population of specific areas. Common field signs include grassy nests or burrows and pathways in undergrowth. Piles of nuts with neatly nibbled holes in them are also a sure sign of voles or mice though the particular species may not always be easy to discern (see below). Dead bank voles are not commonly seen, as predators will tend to consume them whole. Bones and fragments may be found in owl droppings, for example, but may be difficult to identify.
Did you know? The bank vole on Skomer, an island off Wales, has developed into a different sub-species due to the particular living conditions there. The Skomer vole tends to be larger and bolder.
The bank vole was formerly known as Clethrionomys glareolus
Acknowledgements: The Mammal Society, the Wildlife Trusts, Wikipedia
Other Field Signs
Distinctive neatly nibbled holes in hazelnuts are a typical sign of the presence of mice or voles but it is often difficult to distinguish between those nibbled by each species. Nuts that have been nibbled by bank voles and wood mice tend to have vertical tooth marks across the rim of the hole but those nibbled by wood mice tend to be messier. Nuts that have been nibbled by dormice tend to be smoother and more circular, as they nibble round the hole rather than across the rim.
Text: Charlotte Huntly
Photographs: Peter and Jane Howsam, Andy Harmer & Charlotte Huntly
© Shropshire Mammal Group 2020