Voles are small rodents that are relatives of mice, but with a stouter body; a shorter, hairy tail; a slightly rounder head; smaller ears and eyes; and differently formed molars (high-crowned with angular cusps instead of low-crowned with rounded cusps). They are sometimes known as meadow mice or field mice in North America and Australia.
|The bank vole (Myodes glareolus) lives in woodland areas in Europe and Asia.|
|Cladistically included but traditionally excluded taxa|
Voles are small rodents that grow to 3–9 in (7.6–22.9 cm), depending on the species. Females can have five to ten litters per year. Gestation lasts for three weeks and the young voles reach sexual maturity in a month. As a result of this biological exponential growth, vole populations can grow very large within a short time. A mating pair can birth a hundred more voles in a year.
Voles thrive on small plants yet, like shrews, they will eat dead animals and, like mice or rats, they can live on almost any nut or fruit. In addition, voles target plants more than most other small animals, making their presence evident. Voles readily girdle small trees and ground cover much like a porcupine. This girdling can easily kill young plants and is not healthy for trees or other shrubs.
Voles often eat succulent root systems and burrow under plants or ground cover and eat away until the plant is dead. Bulbs in the ground are another favorite target for voles; their excellent burrowing and tunnelling skills give them access to sensitive areas without clear or early warning. The presence of large numbers of voles is often only identifiable after they have destroyed a number of plants. However, like other burrowing rodents, they also play beneficial roles, including dispersing nutrients throughout the upper soil layers.
Many predators eat voles, including martens, owls, hawks, falcons, coyotes, bobcats, foxes, raccoons, snakes, weasels, and lynxes. Vole bones are often found in the pellets of the short-eared owl, the northern spotted owl, the saw-whet owl, the barn owl, the great gray owl, and the northern pygmy owl.
The average life of the smaller vole species is three to six months. These voles rarely live longer than 12 months. Larger species, such as the European water vole, live longer and usually die during their second, or rarely their third, winter. As many as 88% of voles are estimated to die within the first month of life.
The prairie vole is a notable animal model for its monogamous sexual fidelity, since the male is usually faithful to the female, and shares in the raising of pups. The woodland vole is also usually monogamous. Another species from the same genus, the meadow vole, has promiscuously mating males, and scientists have changed adult male meadow voles' behavior to resemble that of prairie voles in experiments in which a single gene was introduced into the brain by a virus.
The behavior is influenced by the number of repetitions of a particular string of microsatellite DNA. Male prairie voles with the longest DNA strings spend more time with their mates and pups than male prairie voles with shorter strings. However, other scientists have disputed the gene's relationship to monogamy, and cast doubt on whether the human version plays an analogous role. Physiologically, pair-bonding behavior has been shown to be connected to vasopressin, dopamine, and oxytocin levels, with the genetic influence apparently arising via the number of receptors for these substances in the brain; the pair-bonding behavior has also been shown in experiments to be strongly modifiable by administering some of these substances directly.
Voles have a number of unusual chromosomal traits. Species have been found with 17 to 64 chromosomes. In some species, males and females have different chromosome numbers, a trait unusual in mammals, though it is seen in other organisms. Additionally, genetic material typically found on the Y chromosome has been found in both males and females in at least one species. In another species, the X chromosome contains 20% of the genome. All of these variations result in very little physical aberration; most vole species are virtually indistinguishable.
Voles may be either monogamous or polygamous, which leads to differing patterns of mate choice and parental care. Environmental conditions play a large part in dictating which system is active in a given population. Voles live in colonies due to the young remaining in the family group for relatively long periods. In the genus Microtus, monogamy is preferred when resources are spatially homogenous and population densities are low and where the opposite of both conditions are realized polygamous tendencies arise. Vole mating systems are also sensitive to the operational sex ratio and tend toward monogamy when males and females are present in equal numbers. Where more one sex is more numerous than the other, polygamy is more likely. However the most marked effect on mating system is population density and these effects can take place both inter and intra-specifically
Male voles are territorial and tend to include territories of several female voles when possible. Under these conditions polyandry exists and males offer little parental care. Males mark and aggressively defend their territories since females prefer males with the most recent marking in a given area.
Voles prefer familiar mates through olfactory sensory exploitation. Monogamous voles prefer males who have yet to mate, while non-monogamous voles do not. Mate preference in voles develops through cohabitation in as little as 24 hours. This drives young male voles to show non-limiting preference toward female siblings. This is not inclusive to females' preference for males which may help to explain the absence of interbreeding indicators.
Although females show little territoriality, under pair bonding conditions they tend to show aggression toward other female voles. This behavior is flexible as some Microtus females share dens during the winter months, perhaps to conserve heat and energy. Populations which are monogamous show relatively minor size differences between genders compared with those using polygamous systems.
The grey-sided vole (Myodes rufocanus) exhibits male-biased dispersal as a means of avoiding incestuous matings. Among those matings that involve inbreeding, the number of weaned juveniles in litters is significantly fewer than that from noninbred litters, due to inbreeding depression.
Brandt’s vole (Lasiopodomys brandtii) lives in groups that mainly consist of close relatives. However, they show no sign of inbreeding. The mating system of these voles involves a type of polygyny for males and extra-group polyandry for females. This system increases the frequency of mating among distantly related individuals, and is achieved mainly by dispersal during the mating season. Such a strategy is likely an adaptation to avoid the inbreeding depression that would be caused by expression of deleterious recessive alleles if close relatives mated.
A 2016 study into the behavior of voles, Microtus ochrogaster specifically, found that voles comfort each other when mistreated, spending more time grooming a mistreated vole. Voles that were not mistreated had levels of stress-hormones that were similar to the voles that had been mistreated, suggesting that the voles were capable of empathizing with each other. This was further proven by blocking the vole's receptors for oxytocin, a hormone involved in empathy. When the oxytocin receptors were blocked this behavior stopped.
This type of empathetic behavior has previously been thought to only occur in animals with advanced cognition, such as humans, apes, and elephants.
The vole clock is a method of dating archaeological strata using vole teeth.
The water voles are large voles in the genus Arvicola. They are found in both aquatic and dry habitat through Europe and much of northern Asia. A water vole found in Western North America was historically considered a member of this genus, but has been shown to be more closely related to members of the genus Microtus.
Head and body lengths are 12–22 cm, tail lengths are 6.5–12.5 cm, and their weights are 70–250 g. The animals may exhibit indeterminate growth. They are thick-furred and have hairy fringes on their feet that improve their swimming ability.Arvicolinae
The Arvicolinae are a subfamily of rodents that includes the voles, lemmings, and muskrats. They are most closely related to the other subfamilies in the Cricetidae (comprising the hamsters and New World rats and mice). Some authorities place the subfamily Arvicolinae in the family Muridae along with all other members of the superfamily Muroidea. Some refer to the subfamily as the Microtinae or rank the taxon as a full family, the Arvicolidae.The Arvicolinae are the most populous group of Rodentia in the Northern Hemisphere. They often are found in fossil occlusions of bones cached by past predators such as owls and other birds of prey. Fossils of this group are often used for biostratigraphic dating of archeological sites in North America and Europe.Bank vole
The bank vole (Myodes glareolus; formerly Clethrionomys glareolus) is a small vole with red-brown fur and some grey patches, with a tail about half as long as its body. A rodent, it lives in woodland areas and is around 100 millimetres (3.9 in) in length. The bank vole is found in western Europe and northern Asia. It is native to Great Britain but not to Ireland, where it has been accidentally introduced, and has now colonised much of the south and southwest.
The bank vole lives in woodland, hedgerows and other dense vegetation such as bracken and bramble. Its underground chamber is lined with moss, feathers and vegetable fibre and contains a store of food. It can live for eighteen months to two years in the wild and over 42 months in captivity and is mostly herbivorous, eating buds, bark, seeds, nuts, leaves and fruits and occasionally insects and other small invertebrates. It readily climbs into scrub and low branches of trees although it is not as versatile as a mouse. It breeds in shallow burrows, the female rearing about four litters of pups during the summer.California vole
The California vole (Microtus californicus) is a type of vole which lives throughout much of California and part of southwestern Oregon. It is also known as the California meadow mouse. It averages 172 mm (6.8 in) in length although this length varies greatly between subspecies.Common vole
The common vole (Microtus arvalis) is a European rodent.European water vole
The European water vole or northern water vole (Arvicola amphibius, included in synonymy: A. terrestris), is a semi-aquatic rodent. It is often informally called the water rat, though it only superficially resembles a true rat. Water voles have rounder noses than rats, deep brown fur, chubby faces and short fuzzy ears; unlike rats their tails, paws and ears are covered with hair.
In the wild, on average, water voles only live about five months. Maximum longevity in captivity is two and a half years.Field vole
The field vole or short-tailed vole (Microtus agrestis) is a grey-brown vole, around four inches (ten centimetres) in length, with a short tail. It is one of the most common mammals in Europe, with a range extending from the Atlantic coast to Lake Baikal. These voles are found in moist grassy habitats, such as woodland, marsh or on river banks. Although they make shallow burrows, they usually build nests above ground. They are an important food source for owls and some other predators and their population size tends to peak and trough cyclically. Field voles breed prolifically, mainly in summer, but often all year round, even under snow. Females produce up to seven litters a year, each averaging from four to six young which are weaned after about fourteen days. The field vole is both widespread and common and is listed as being of "Least Concern" by the IUCN.Lemming
A lemming is a small rodent, usually found in or near the Arctic in tundra biomes. Lemmings make up the subfamily Arvicolinae (also known as Microtinae) together with voles and muskrats, which form part of the superfamily Muroidea, which also includes rats, mice, hamsters, and gerbils.Long-tailed vole
The long-tailed vole (Microtus longicaudus), in some areas known as the San Bernardino long-tailed vole, is a small vole found in western North America. They have short ears and a long tail. Their fur is gray brown with light gray underparts. They are around 18 cm (7.1 in) long with an 8 cm (3.1 in) tail and weigh about 50 g (1.8 oz).Meadow vole
The meadow vole (Microtus pennsylvanicus), sometimes called the field mouse or meadow mouse, is a North American vole found across Canada, Alaska and the northern United States. Its range extends farther south along the Atlantic coast. One subspecies, the Florida salt marsh vole (M. p. dukecampbelli), is found in Florida, and is classified as endangered. Previously it was also found in Chihuahua, Mexico, but has not been recorded since 1998.
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.Microtus
Microtus is a genus of voles found in North America, Europe, and northern Asia. The genus name refers to the small ears of these animals. About 62 species are placed in the genus.
They are stout rodents with short ears, legs, and tails. They eat green vegetation such as grasses and sedges in summer, and grains, seeds, roots, and bark at other times. The genus is also called "meadow voles". (ITIS database)
The species are:
Insular vole (M. abbreviatus)
California vole (M. californicus)
Rock vole (M. chrotorrhinus)
Long-tailed vole (M. longicaudus)
Mexican vole (M. mexicanus)
Singing vole (M. miurus)
Water vole (M. richardsoni)
Zempoaltépec vole (M. umbrosus)
Taiga vole (M. xanthognathus)Subgenus Microtus
Field vole (M. agrestis)
Anatolian vole (M. anatolicus)
Common vole (M. arvalis)
Cabrera's vole (M. cabrerae)
Doğramaci's vole (M. dogramacii)
Günther's vole (M. guentheri)
Tien Shan vole (M. ilaeus)
Persian vole (M. irani)
Southern vole (M. levis)
Paradox vole (M. paradoxus)
Qazvin vole (M. qazvinensis)
Schidlovsky's vole (M. schidlovskii)
Social vole (M. socialis)
Transcaspian vole (M. transcaspicus)Subgenus Terricola
Bavarian pine vole (M. bavaricus)
Calabria pine vole (M. brachycercus)
Daghestan pine vole (M. daghestanicus)
Mediterranean pine vole (M. duodecimcostatus)
Felten's vole (M. felteni)
Gerbe's vole (M. gerbei)
Liechtenstein's pine vole (M. liechtensteini)
Lusitanian pine vole (M. lusitanicus)
Major's pine vole (M. majori)
Alpine pine vole (M. multiplex)
Savi's pine vole (M. savii)
European pine vole (M. subterraneus)
Tatra pine vole (M. tatricus)
Thomas's pine vole (M. thomasi)Subgenus Mynomes
Beach vole (M. breweri)
Gray-tailed vole (M. canicaudus)
Montane vole (M. montanus)
Creeping vole (M. oregoni)
Meadow vole (M. pennsylvanicus)
Townsend's vole (M. townsendii)Subgenus Alexandromys
Clarke's vole (M. clarkei)
Evorsk vole (M. evoronensis)
Reed vole (M. fortis)
Taiwan vole (M. kikuchii)
Lacustrine vole (M. limnophilus)
Maximowicz's vole (M. maximowiczii)
Middendorf's vole (M. middendorffi)
Mongolian vole (M. mongolicus)
Japanese grass vole (M. montebelli)
Muisk vole (M. mujanensis)
Tundra vole or root vole (M. oeconomus) - several subspecies
Sakhalin vole (M. sachalinensis)Subgenus Stenocranius
Narrow-headed vole (M. gregalis)Subgenus Pitymys
Guatemalan vole (M. guatemalensis)
Tarabundí vole (M. oaxacensis)
Woodland vole (M. pinetorum)
Jalapan pine vole (M. quasiater)Subgenus Pedomys
Prairie vole (M. ochrogaster)Subgenus Hyrcanicola
Schelkovnikov's pine vole (M. schelkovnikovi)Muskrat
The muskrat (Ondatra zibethicus), the only species in genus Ondatra and tribe Ondatrini, is a medium-sized semiaquatic rodent native to North America and an introduced species in parts of Europe, Asia, and South America. The muskrat is found in wetlands over a wide range of climates and habitats. It has important effects on the ecology of wetlands, and is a resource of food and fur for humans.
The muskrat is the largest species in the subfamily Arvicolinae, which includes 142 other species of rodents, mostly voles and lemmings. Muskrats are referred to as "rats" in a general sense because they are medium-sized rodents with an adaptable lifestyle and an omnivorous diet. They are not, however, members of the genus Rattus.Norway lemming
The Norway lemming, also Norwegian lemming (Lemmus lemmus) is a common species of lemming found in northern Fennoscandia. It is the only vertebrate species endemic to the region. The Norway lemming dwells in tundra and fells, and prefers to live near water. Adults feed primarily on sedges, grasses and moss. They are active at both day and night, alternating naps with periods of activity.Orkney vole
The Orkney vole (Microtus arvalis orcadensis) is a population of the common vole (Microtus arvalis) found in the Orkney Islands, off the northern coast of Scotland, United Kingdom. Orkney voles are larger than voles from other populations of the common vole. The common vole does not occur elsewhere in the British Isles.
The Orkney vole occurs on five islands:
South RonaldsayIn the past the populations on each of these islands have been named as subspecies, and the Orkney vole as a whole is considered by some taxonomists to be a subspecies of the common vole because of its size difference from the common vole. However, others do not recognise any subspecies of the common vole, especially since DNA analysis indicates transport by Neolithic humans from Belgium.Orkney voles do not occur in mainland Britain, nor elsewhere in the British Isles, and they are thought to have been introduced to the Orkney archipelago by humans in Neolithic times. The oldest known radiocarbon-dated fossil of Common Vole in Orkney is 4,600 years old: this marks the latest possible date of introduction.Prairie vole
The prairie vole (Microtus ochrogaster) is a small vole found in central North America.
The vole has long, coarse grayish-brown fur on the upper portion of the body and yellowish fur on the lower portion of the body. It has short ears and a short tail, which is somewhat darker on top.Red-backed vole
Red-backed voles are small, slender voles of the genus Myodes found in North America, Europe, and Asia. The genus name comes from the Greek "keyhole mouse". In the past, the genus has been called Evotomys or Clethrionomys, but Myodes takes precedence.
Red-backed voles inhabit northern forests, tundra and bogs. They feed on shrubs, berries and roots. Most species have reddish brown fur on their back. They have small eyes and ears. Unlike other voles, the molar teeth are rooted in adults.
The complete list of species is:
Japanese red-backed vole, Myodes andersoni
Western red-backed vole, Myodes californicus
Tien Shan red-backed vole, Myodes centralis
Southern red-backed vole, Myodes gapperi
Bank vole, Myodes glareolus
Imaizumi's red-backed vole, Myodes imaizumii
Korean red-backed vole, Myodes regulus
Hokkaido red-backed vole, Myodes rex
Grey red-backed vole, Myodes rufocanus
Northern red-backed vole, Myodes rutilus
Shansei vole, Myodes shanseius
Smith's vole, Myodes smithiiSagebrush vole
The sagebrush vole (Lemmiscus curtatus) is a tiny vole found in western North America. This is the only member of genus Lemmiscus.
They are somewhat similar in appearance to lemmings. They have chunky bodies with short legs and a very short tail which is covered in fur and lighter below. They have fluffy dull grey fur with lighter underparts. They range from 11-14 cm in length with a tail length of around 1.8-2.7 cm and a mass of around 21-39 g.These animals are found in dry open brushy areas in the western United States and southern parts of western Canada. They feed on grasses and leaves in summer and sagebrush, bark and twigs in winter. Predators include owls, coyotes, bobcats and weasels.
Female voles have 5 or more litters of 4 to 6 young in a year. The young are born in a nest in a burrow.
They are active year-round, day and night, but are usually more active near sunrise and sunset. They make trails through the surface vegetation and also dig underground burrows with many entrances. They burrow under the snow in winter. These animals are often found in colonies.Southern red-backed vole
The southern red-backed vole or Gapper's red-backed vole (Myodes gapperi) is a small slender vole found in Canada and the northern United States. It is closely related to the western red-backed vole (Myodes californius), which lives to the south and west of its range and which is less red with a less sharply bicolored tail.
These voles have short slender bodies with a reddish band along the back and a short tail. The sides of the body and head are grey and the underparts are paler. There is a grey color morph in the northeast part of their range. They are 12–16.5 cm (4.7–6.5 in) long with a 4 cm tail and weigh about 6–42 g; average 20.6 g (0.21–1.48 oz; average 0.72 oz).
These animals are found in coniferous, deciduous, and mixed forests, often near wetlands. They use runways through the surface growth in warm weather and tunnel through the snow in winter. They are omnivorous feeding on green plants, underground fungi, seeds, nuts, roots, also insects, snails, and berries. They store roots, bulbs, and nuts for later use.
Predators include hawks, owls, and mustelids.
Female voles have two to four litters of two to eight young in a year.They are active year-round, mostly at night. They use underground burrows created by other small animals.Tundra vole
The tundra vole (Microtus oeconomus) or root vole is a medium-sized vole found in Northern and Central Europe, Asia, and northwestern North America, including Alaska and northwestern Canada. In the western part of the Netherlands, the tundra vole is a relict from the ice age and has developed to the subspecies Microtus oeconomus arenicola.
It has short ears and a short tail. Its fur is yellowish brown with paler sides and white underparts. They are about 18 cm (7.1 in) long with a 4 cm (1.6 in) tail and weigh about 50 grams (1.8 oz).
This species is found in damp tundra or moist meadows, usually near water. It makes runways through the surface growth in warm weather and tunnels through the snow in winter. It feeds on grasses, sedges and seeds.
Female voles have three to six litters of three to 9 young in a shallow burrow. The vole population in a given area can vary greatly from year to year.
It is active year-round. It also digs underground burrows where it stores seeds and roots, especially licorice root, for the winter. The species epithet oeconomus refers to this "economical" behaviour.