Meadow vole

Distribution

The meadow vole has the widest distribution of any North American species of Microtus. It ranges from Labrador west to Alaska and south from Labrador and New Brunswick to South Carolina and extreme northeastern Georgia; east through Tennessee, Missouri, north-central Nebraska, the northern half of Wyoming, and central Washington to Alaska; south through Idaho into north-central Utah. It is excluded only from the extreme polar regions. A disjunct subset of its range occurs from central Colorado to northwestern New Mexico.

Behavior

The meadow vole is active year-round, usually at night. It also digs underground burrows, where it stores food for the winter and females give birth to their young. Although these animals tend to live close together, they are aggressive towards one another. This is particularly evident in males during the breeding season. They can cause damage to fruit trees, garden plants and commercial grain crops.

Habitat

Optimal meadow vole habitat consists of moist, dense grassland with substantial amounts of plant litter. Habitat selection is largely influenced by relative ground cover of grasses and forbs; soil temperature, moisture, sodium, potassium, and pH levels; humidity; and interspecific competition.

Meadow voles are most commonly associated with sites having high soil moisture.

Reproduction

Gestation lasts 20 to 23 days. Neonates are pink and hairless, with closed eyes and ears. Fur begins to appear by three days, and young are completely furred except for the belly by seven days.

Eyes and ears open by eight days. Weaning occurs from 12 to 14 days. Young born in spring and early summer attain adult weight in 12 weeks, but undergo a fall weight loss. Young born in late summer continue growing through the fall and maintain their weight through the winter. Maximum size is reached between two and 10 months.

Typical meadow vole litters consist of four to six young, with extremes of one and 11 young. On average 2.6 young are successfully weaned per litter.

Food

Meadow voles eat most available species of grasses, sedges, and forbs, including many agricultural plant species.

In winter, meadow voles consume green basal portions of grass plants, often hidden under snow. Other winter diet components include seeds, roots, and bulbs. They occasionally strip the bark from woody plants. Seeds and tubers are stored in nests and burrows. Evidence of coprophagy is sparse. but thought to occur.

Predators

Meadow voles are an important prey for many hawks, owls, and mammalian carnivores, and they are also taken by some snakes. Almost all species of raptors take microtine rodents as prey.

Birds not usually considered predators of mice do take voles; examples include gulls, northern shrike, black-billed magpie, common raven, American crow, great blue heron, and American bittern.