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.

Biogeographic Regions: nearctic (Native )

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.

Biogeographic Regions: nearctic (Native )

occurs (regularly, as a native taxon) in multiple nations

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Global Range: Most of forested Canada (northern British Columbia to Labrador) south through the Rocky Mountains to central New Mexico and east-central Arizona, northern Great Plains (to Iowa), northern Great Lakes, New England and Appalachian Mountains (to northern Georgia).

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.

Range mass: 6 to 42 g.

Average mass: 20.57 g.

Range length: 95 to 172 mm.

Sexual Dimorphism: sexes alike

The head and body length of red-backed voles varies between 70 and 112 mm. The tail is 25 to 60 mm long. Weights between 6 and 42 g have been recorded.

Red-backed voles have dense, long, soft fur in winter but this changes to shorter, coarser fur in summer. The general coloration above is dark gray with a pronounced chestnut brown stripe running along the back from head to tail. Face and sides appear yellowish brown and the underparts are dark slate gray to almost white. Males and females are similar in size and color, and young animals tend to be darker than adults.

Range mass: 6 to 42 g.

Average mass: 20.57 g.

Range length: 70 to 112 mm.

Sexual Dimorphism: sexes alike

Length: 16 cm

Weight: 42 grams

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.

Habitat Regions: temperate ; terrestrial

Terrestrial Biomes: tundra ; taiga ; forest

• Terrestrial

Red-backed voles inhabit cool, mossy and rocky boreal forests in both dry and moist areas. They also inhabit tundra and bogs. Coniferous forests are preferred habitat, although deciduous or mixed coniferous/deciduous woods are also accepted. Nests are generally constructed under the roots of stumps, logs, or brush piles, but may be located in holes or branches of trees high above the ground.

Habitat Regions: temperate ; terrestrial

Terrestrial Biomes: tundra ; taiga ; forest

Comments: Prefers cool, mesic deciduous, coniferous, or mixed forests, especially areas with large amount of ground cover. Regarded as an ecological indicator of old-growth conditions in the Rocky Mountains. Also uses second-growth areas. Mossy logs and tree roots in coniferous forests are optimal. In the northern part of its range also found in muskegs, sedge marshes, shrubby habitats, and treed peatlands (Merritt, in Wilson and Ruff 1999). Often on rock outcrops in some areas (e.g., Virginia). Often associated with abandoned stone walls (fences) in the northeastern U.S. In Pennsylvania, abundance increased with forest fragmentation (Yahner 1992). Nests under logs, stumps and roots. Unlike Microtus, doesn't dig tunnels, but uses the burrows of moles and other small mammals.

Non-Migrant: Yes. At least some populations of this species do not make significant seasonal migrations. Juvenile dispersal is not considered a migration.

Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: No. No populations of this species make annual migrations of over 200 km.

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.

Animal Foods: insects

Plant Foods: leaves; roots and tubers; wood, bark, or stems; seeds, grains, and nuts; fruit; flowers

Other Foods: fungus

Foraging Behavior: stores or caches food

Red-backed voles are opportunistic feeders and change their diet as the seasons progress. They eat leaf petioles and young shoots in the spring, add fruits and berries to their diet in the summer, and then switch to nuts and seeds in the autumn. They also consume some bark, roots, lichens, fungi, and insects. They sometimes store food in their nests for use in the winter when it becomes difficult to forage, although they continue to forage for seeds, tree roots, and bark under the snow.

Animal Foods: insects

Plant Foods: leaves; roots and tubers; wood, bark, or stems; seeds, grains, and nuts; fruit; flowers

Other Foods: fungus

Foraging Behavior: stores or caches food

Primary Diet: omnivore

Comments: Feeds chiefly on vegetation, seeds, nuts, fungi, some insects; summer diet in Colorado (and much of western U.S.) consists almost entirely of fungi.

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 are eaten by a number of predatory species. Strigiformes, Accipitriformes, Mustelidae, Ursus americanus, Lynx canadensis, Lynx rufus, Canis latrans, Vulpes vulpes, and Canis lupus are all likely predators of these small rodents.

Known Predators:

• Canada lynx, Lynx_canadensis
• bobcats, Lynx_rufus
• coyotes, Canis_latrans
• wolves, Canis_lupus
• black bears, Ursus_americanus
• foxes, Vulpes_vulpes
• owls, Strigiformes
• hawks, Accipitriformes
• mustelids, Mustelidae

These animals are likely to play some role in local food webs. As a prey item, these voles provide food for many other species. As predators, they may have a great impact on some insect populations. In addition, they help to disperse seeds.

Red-backed voles are almost certainly eaten by a number of predatory species. Owls, hawks, mustelids, black bears, Canada lynx, bobcats, coyotes, foxes, and wolves are all likely predators of these small rodents.

Known Predators:

• Canada lynx, Lynx canadensis 
• bobcat, Lynx rufus 
• coyote, Canis latrans 
• Wolf, Canis lupus 
• Black bear, Ursus americanus 
• fox, Vulpes vulpes 
• owls
• hawks

Disperses viable spores of mycorrhizal fungi and nitrogen-fixing bacteria (see Maser and Maser 1988).

Home range varies from 0.25 to 3.5 acres (Merritt and Merritt 1978). Experimentation by Gillis and Nams (1998) suggests that populations separated by an inter-patch distance of 60-70 m likely would be isolated from one another. Mature females are territorial. Populations noncyclic.

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.

Communication Channels: visual ; tactile ; acoustic ; chemical

Perception Channels: visual ; acoustic

Communication in these animals has not been thoroughly described. Some vocalizations are used. When disturbed, red-backed voles utter a chirplike bark that can be heard 1 to 2 m away. They also gnash or chatter their teeth.

In addition, visual cues such as body posture may be of some importance in interactions with members of the same species.

The role of chemical signals in these animals remains unknown, although it is likley that some information is transmitted through scents.

Tactile communication is important in aggression, as well as in the relationship between a mother and her offspring.

Communication Channels: visual ; tactile ; acoustic ; chemical

Perception Channels: visual ; acoustic

Comments: Mainly nocturnal, active year-long.

Red-backed voles can live 20 months in the wild. However, most voles only live as long as 12 to 18 months

Range lifespan

Status: wild: 20 (high) months.

Typical lifespan

Status: wild: 12 to 18 months.

Red-backed voles can live in the wild to be 20 months. However, most voles only live as long as 12 to 18 months

Range lifespan

Status: wild: 20 (high) months.

Typical lifespan

Status: wild: 12 to 18 months.

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.

Breeding interval: Breeding of red-backed voles occurs every 1.5 months during warm weather.

Breeding season: Breeding season of red-backed voles extends from March through November.

Range number of offspring: 1 to 11.

Average number of offspring: 3 to 7.

Range gestation period: 17 to 19 days.

Range weaning age: 17 to 21 days.

Average age at sexual or reproductive maturity (female): 3 months.

Average age at sexual or reproductive maturity (male): 3 months.

Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); fertilization ; viviparous

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.

Parental Investment: altricial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female)

The mating system of these animals has not been described.

Breeding may begin as early as late winter and continue to late fall, so that females are generally able to rear 2 or 3 litters each year. Gestation is 17 to 19 days, and litter size is from 1 to 11 young, although the average is 3 to 7, depending on environmental conditions.

Offspring are born naked and blind. They are able to stand when 4 days old, have fur by day 8, open their eyes by 15 days and are weaned at 17 to 21 days. Sexual maturity occurs at approximately 3 months. Average life span in the wild is 10 to 12 months, with a maximum reported longevity of 20 months.

Breeding interval: Breeding occurs every 1.5 months during warm weather.

Breeding season: Breeding season extends from March through November.

Range number of offspring: 1 to 11.

Average number of offspring: 3-7.

Range gestation period: 17 to 19 days.

Range weaning age: 17 to 21 days.

Average age at sexual or reproductive maturity (female): 3 months.

Average age at sexual or reproductive maturity (male): 3 months.

Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); fertilization ; viviparous

The parental behavior of these animals has not been described. However, because they are mammals, we know that the mother provides some care for the young. Mothers nurse their offspring for 17 to 21 days after birth, and provide the young with a protective nest in which to live. It is not known whether males help to care for the young.

Parental Investment: altricial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female)

Breeds mid-January to late November; peak activity February-October. Gestation lasts 17-19 days. Litters size is 1-9 (average 5.6 in Alberta, 6.5 in Colorado). Litters/year: 1-4 for young, 1-6 for older females in Alberta; 2/year in Colorado (young of year breed).

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.

IUCN Red List of Threatened Species: least concern

US Federal List: no special status

CITES: no special status

State of Michigan List: no special status

Populations of Myodes gapperi 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.

US Federal List: no special status

CITES: no special status

State of Michigan List: no special status

IUCN Red List of Threatened Species: least concern

Canada

Rounded National Status Rank: N5 - Secure

United States

Rounded National Status Rank: N5 - Secure

Rounded Global Status Rank: G5 - Secure

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.

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. They have been found to be important in some areas as agents in transporting and burying seeds, although some seeds are obviously eaten.

Comments: Includes subspecies occidentalis and caurinus, which formerly were included in the species now known as Myodes californicus. Some authors have suggested that rutilis and gapperi are conspecific, but this has not been accepted by most authorities (Jones et al. 1992; Musser and Carleton, in Wilson and Reeder 1993, 2005).

See Musser and Carleton (in Wilson and Reeder 2005) for an extensive discussion of the basis for correcting the generic name from Clethrionomys to Myodes.