The Field Vole resembles a small mouse, but with a stouter body and shorter tail. Also known as 'field mice', these rodents are accomplished tunnel diggers, burrowing the ground in search of roots and bulbs, which they feed upon. In fact, the Field Vole is one of the most frequently found small rodents in the countryside of Britain and Europe. This animal doesn't tend to enter houses, but can often be seen in backyards. Its coat is greyish-brown on the upper-parts and creamy-grey on the under-parts. The ears of field vole are rounded and furred, while the eyes are less prominent as compared to mice.
The range of the field vole covers a huge territory across northern Europe, stretching from north-west Spain to Russia. However, they are most common in Britain and offshore islands (except for Ireland). Preferred habitat of these rodents is ungrazed grassland with abundance of vegetation. They occur in a wide variety of environments such as meadows, margins of fields, forestry plantations, hedgerows, dunes, open moorland and blanket bogs.
Period of increased activity in this species is dusk. However, they can be active during both day and night. Field voles are solitary and highly territorial animals, fiercely and aggressively defending their territories from intruders. When fighting, they are extremely noisy, emitting loud squeaking sounds and giving out angry chattering noises. Each individual makes paths through the grass stems, starting from a tussock, where nesting site is located. Despite their digging habits, these voles nest above the surface on grass stems, which are often protected by a stone or log. They are known to store grass for winter, collecting it in small underground burrows, which they dig themselves. For safety reasons, Field voles open paths through high grass, which help them easily run and flee when threatened, returning to their burrows through these routes. These rodents also have special defecation sites, where they leave characteristic little piles of chopped up grass stalks.
Field voles are predominantly herbivorous. Their diet mainly consists of grass stems and green leaves, supplemented with roots, bulbs and bark, especially during the winter months, when there's scarcity of fresh vegetation. In addition, these rodents are known to consume invertebrates such as insect larvae.
Little is known about the Field voles’ mating system. However, it is known that most vole species are polygynous. They breed from March-April to October-December. Field voles construct their nests both under and above the ground, typically in clumps of grass or sedge. Gestation period lasts for 3 weeks, giving birth to 4 - 6 young. Females of this species can yield 2 - 7 litters per year. Newborn field voles grow rapidly. They feed upon maternal milk for 12 days, leaving the nest by 21 days old, after which female offspring live within or near the home range of their mother. Meanwhile, young males immediately disperse, being driven away by adult males. Females are sexually mature at 28 days old, whereas males reach maturity within 40 days after birth.
Field voles are affected by a number of factors throughout their range. Thus, they suffer from overgrazing, poisoning by rodenticides, scrub growth, urban development, decline of rough grassland as well as lack of hedgerows and other linear objects.
The Field vole is common and widespread throughout its range but the global population size of this species is unknown. However, according to The Mammal society, a recent population estimate put the number of Field voles in Britain at 75,000,000 individuals. Currently, this species is classified as Least Concern (LC), and its numbers remain stable.
Field voles have an important role as key prey for their natural predators (barn owls, kestrels, other owls, weasels, stoats, foxes and snakes).