Myodes gapperi
The head and body of red-backed voles measure from 70 to 112 mm in length. The tail is an additional 25 to 60 mm. On average, they weigh 20.57 g, but individuals weighing between 6 and 42 g have been recorded. Red-backed voles have dense, long, soft fur in winter, and shorter, coarser fur in summer. They are dark gray, and have a reddish-brown stripe from head to tail along their backs. Their faces and sides are a lighter yellowish-brown, and their bellies can be dark gray to almost white. Males and females are similar in size and color. Young animals tend to be darker than adults.
Red-backed voles, Myodes gapperi, range from British Columbia to mainland Newfoundland and throughout the northern United States from the Rocky Mountains to the Appalachians.
Red-backed voles live mainly in coniferous forests. Although they prefer evergreens, these voles also live in deciduous or mixed coniferous/deciduous woods. Sometimes they live in tundra and bog habitats.
Red-backed voles build their nests under the roots of stumps, logs, or brush piles. Nests may also be located in holes or branches of trees high above the ground.
The mating system of red-backed voles has not been described.
Red-backed voles breed in all but the coldest months. Mating occurs from March until November. A healthy female can rear 2 or 3 litters in a year. Pregnancy lasts 17 to 19 days. Litters can have from 1 to 11 young, although 3 to 7 is more typcial.
Red-backed voles are naked and blind when they are born. They develop quickly and are able to stand by the time they are 4 days old. Babies gain fur by 8 days of age and open their eyes by 15 days. Mothers stop nursing their young when they are 17 to 21 days old. It is likley that young voles become independent around this time. Red-backed voles are able to reproduce at around 3 months of age.
Little is known about the parental behavior of red-backed voles. Mothers nurse their young for 17 to 21 days after birth. They also shelter their babies in a protective nest. It is not known whether males help to care for the young.
Red-backed voles can live 20 months in the wild. However, most voles only live as long as 12 to 18 months
Red-backed voles are active mostly at night, but they can be active during the day. They do not hibernate. Most of the time, they stay close to fallen logs or rocks. They sometimes move though underground passages when they look for food. Red-backed voles usually hop rather than run, and they are agile jumpers and climbers. They do not usually make runways of their own, but they use runways made by other small mammals such as shrews or moles.
Red-backed voles create ball-shaped nests that are made of grasses, mosses, lichens, or shredded leaves. During the winter, these are sometimes created directly on the ground under the snow. Tunnels radiate outward from the nest under the snow.
Red-backed voles utter a chirplike bark when they are disturbed. This can be heard 1 to 2 m away. They may flee or freeze in position, depending on what they are doing when they are disturbed. They also gnash or chatter their teeth.
Red-backed voles are solitary, and do not let other red-backed voles near their homes. They fight with other species as well. The only friendly interactions among individuals are between a mother and her offspring.
Home ranges range in size from 0.14 ha in the winter to 1.4 ha in the summer (0.5 ha is most common) and as small as 0.14 ha in the winter, when foraging is restricted by a blanket of snow.
Communication in red-backed voles has not been well studied. However, they can hear, and vocalizations are sometimes used to communicate. When they are disturbed, red-backed voles make a chirplike bark that can be heard 1 to 2 m away. They also gnash or chatter their teeth.
Visual cues such as body posture may be of some importance in interactions with other voles. Scents may also help these voles to communicate. It is likely that some information is transmitted through scents in the urine or associated with reproduction. Tactile communication is important in fighting, as well as in the relationship between a mother and her young.
Red-backed voles are omnivores, and their diet changes with the seasons. They eat leaves and shoots in the spring. Fruits and berries are eaten in the summer. Nuts and seeds are eaten during the fall. They also eat bark, roots, lichens, fungi, and insects. Red-baked voles sometimes store food in their nests for use in the winter, but they continue to look for seeds, tree roots, and bark under the snow.
Red-backed voles are eaten by a number of predatory species. Owls, hawks, mustelids, black bears, Canada lynx, bobcats, coyotes, red foxes, and wolves are all likely predators of these small rodents.
Red-backed voles are prey to a variety of species. They also consume insects and plant materials, and may help disperse seeds.
Red-backed voles may damage or kill tree seedlings, and they also eat a large number of seeds. This has been of little economic importance to humans, however.
Red-backed voles destroy harmful insect larvae and are also a major source of food for fur-bearing animals. Although some seeds are eaten, they are important agents in transporting and burying seeds in some areas.
Populations of red-backed voles often fluctuate widely from year to year but with no apparent periodicity. Numbers are fairly low in most of the species range, however, with an average of approximately 2 to 3 voles per acre in favorable habitat.
Tanya Dewey (editor), University of Michigan-Ann Arbor, George Hammond (editor), Animal Diversity Web Staff, Gail McCormick (editor), Animal Diversity Web Staff.
Nancy Shefferly (editor), Animal Diversity Web Staff.
Liz Ballenger (author), University of Michigan-Ann Arbor.
Jackson, H.H.T. 1961. Mammals of Wisconsin. The University of Wisconsin Press, Madison, Wisconsin.
Kurta, A. 1995. Mammals of the Great Lakes Region. The University of Michigan Press, Ann Arbor, Michigan.
Nowak, R.M. and J.L Paradiso. 1983. Walker's Mammals of the World. 4th edition. John Hopkins University Press, Baltimore, Maryland.