Montane vole | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Rodentia |
Family: | Cricetidae |
Subfamily: | Arvicolinae |
Genus: | Microtus |
Subgenus: | Pitymys |
Species: | M. montanus |
Binomial name | |
Microtus montanus (Peale, 1848) | |
The montane vole (Microtus montanus) is a species of vole native to the western United States and Canada. [1]
Montane voles are medium-sized voles, with a total length of 14 to 22 cm (5.5 to 8.7 in), including the 2 to 7 cm (0.79 to 2.76 in) tail. Adults typically weigh anything from 37 to 85 grams (1.3 to 3.0 oz), with males being slightly larger than females, but the actual weight varies considerably with age, geography, and subspecies. The upper body is covered with fur of a dark brownish shade, again with some variation between individuals. The fur is paler on the flanks, and fades to grey or white on the underparts. The tail exhibits the same color variation, with the fur being dark brown to almost black on the upper surface and grey or white below. [2]
Montane voles possess scent glands on the hips, near the anus, and on the male genitalia. These glands increase in size in response to testosterone, and are therefore particularly large in adult males. [3] At least some of these glands produce unique fatty acid esters, that may function in species recognition. [4] Females have four pairs of teats, running from the chest to the groin. [2]
Montane voles are found in mountainous and other high elevation terrain in the western United States and Canada. [5] Within this region they are generally found in drier climates than other species of vole, and in areas more dominated by grassland than by shrubs. [2] [6] Typical habitats include alpine meadows and grassy areas near streams or lakes; they are also often found in cropland or pasture. [1] Fossils of montane voles have been recovered from as far back as the Irvingtonian, when they appear to have been more widespread across what is now the southwestern United States. [2]
At least fourteen subspecies of montane vole are recognized: [2]
Montane voles are herbivorous, although they may also eat small numbers of insects and other arthropods. The majority of their diet consists of forbs, supplemented by seeds, grasses, and fungi. One study in Colorado found that favored foods included vetch and evening primrose. [7] Predators include a range of hawks and owls, weasels, and even coyotes. [2] Montane voles have been reported to form up to 80% of the diet of great horned owls in Idaho. [8]
Montane voles have also been used in the laboratory in studies of African sleeping sickness, since they suffer similar symptoms to humans when infected with the parasite. [2]
Montane voles are nocturnal during the summer, but primarily diurnal during winter. [9] They often inhabit abandoned gopher burrows, although they are also capable of digging their own. [10] Typical burrows are 100 cm (39 in) in length, and reach a depth of 20 cm (7.9 in), although there is considerable variation. [2] Montane voles also construct nests, which are typically cup-shaped, [10] although those used for raising young are globular and about 13 cm (5.1 in) in diameter. [11] Males mark their territory with urine and dung and by rubbing their anal scent glands along the ground. [12]
The breeding season begins in April or May, and continues until at least August. [13] The start of the season is triggered by chemicals found in fresh spring grass, [14] and coincides with the snowmelt. Since chemicals in older, late summer grass, depress the reproductive drive, the exact end of the season may vary from year to year, and some individuals have been reported to breed in midwinter in recent decades. [2]
Males mate with multiple females if the opportunity arises, [15] and have no preference for unmated females over those that have previously mated. [16] Females do not have regular estrus cycles, [17] and their reproductive status is apparently induced by chemical signals from nearby males. [18]
Gestation lasts 21 days, and results in the birth of five to eight pups. [19] The young are born blind and helpless, and are not capable of standing until four days after birth, around the time that they first begin to develop fur. Their eyes open after about ten days, and they are weaned at around fourteen days. [20] The pups leave the nest a day or so after weaning, when the female begins to prepare for a new litter. [19]
The female may raise three to four litters in a year. Young born early in the year may reach sexual maturity in as little as four weeks, but those born in the fall do not do so until spring. [21]
Voles are small rodents that are relatives of lemmings and hamsters, but with a stouter body; a longer, hairy tail; a slightly rounder head; smaller eyes and ears; and differently formed molars. They are sometimes known as meadow mice or field mice in North America.
The northern short-tailed shrew is the largest shrew in the genus Blarina, and occurs in the northeastern region of North America. It is a semifossorial, highly active, and voracious insectivore and is present in a variety of habitats like broadleaved and pine forests among shrubs and hedges as well as grassy river banks. It is notable in that it is one of the few venomous mammals. The specific epithet, brevicauda, is a combination of the Latin brevis and cauda, meaning "short tail".
The desert woodrat is a species of pack rat native to desert regions of western North America.
The eastern meadow vole, sometimes called the field mouse or meadow mouse, is a North American vole found in eastern Canada and the United States. Its range extends farther south along the Atlantic coast.
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. They are stout rodents with short ears, legs and tails. They eat green vegetation such as grasses and sedges in summer, and grains, seeds, root and bark at other times. The genus is also called "meadow voles".
The North American water vole or just water vole is the largest North American vole. It is found in the northwestern United States and southern parts of western Canada. This animal has been historically considered a member of genus Arvicola, but molecular evidence demonstrates that it is more closely related to North American Microtus species. Water voles are on the USDA Forest Service Region 2 sensitive species list because they maintain very small populations and there is high concern that their required habitat may be declining.
The southern bog lemming is a small North American lemming. Its range overlaps with the other species in genus Synaptomys, the northern bog lemming, in southeastern Canada, but extends farther south.
The long-tailed vole, 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).
The eastern heather vole,, is a small North American vole. Until recently, this species was considered to belong to the same species as the western heather vole, Phenacomys intermedius. It is also called the Ungava vole.
The woodland vole is a small vole found in eastern North America. It is also known as the pine vole.
The prairie vole is a small vole found in central North America.
Scent gland are exocrine glands found in most mammals. They produce semi-viscous secretions which contain pheromones and other semiochemical compounds. These odor-messengers indicate information such as status, territorial marking, mood, and sexual behaviour. The odor may be subliminal—not consciously detectable. Though it is not their primary function, the salivary glands may also function as scent glands in some animals.
Peromyscus maniculatus is a rodent native to eastern North America. It is most commonly called the eastern deer mouse; when formerly grouped with the western deer mouse, it was referred to as the North American deermouse and is fairly widespread across most of North America east of the Mississippi River, with the major exception being the lowland southeastern United States.
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.
The gray-tailed vole also known as the gray-tailed meadow vole or gray-tailed meadow mouse, is a rodent in the genus Microtus of the family Cricetidae. Voles are small mammals, and this species lies roughly in the middle of their size range. First collected in 1895, it is endemic to the Willamette Valley, Oregon, and Clark County, Washington, in the Pacific Northwest region of North America. Historically, they were found in the prairie areas of the Valley and, though many of these areas have been converted for agricultural purposes, these animals remain common. For reasons that remain unclear, vole population densities in any area may fluctuate widely from season to season and year to year. They are preyed upon by owls, hawks, and carnivorous mammals, and their parasites include fleas and ticks. These voles build burrows and complex tunnel networks, which they sometimes share with other burrowing animals. Relatively little is known about their behavior in the wild, because they are elusive and unlikely to enter traps.
The California vole 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", a misnomer as this species is a vole, not a mouse. It averages 172 mm (6.8 in) in length although this length varies greatly between subspecies.
The beach vole or Muskeget vole is a rodent in the family Cricetidae. This close relative of the eastern meadow vole is endemic to the 0.87 km2 Muskeget Island, Massachusetts. Due to its relatively short period of reproductive isolation, there is debate over the beach vole's designation as a subspecies of M. pennsylvanicus.
The flank gland is one of several specialized posterolateral glands found predominately in certain species of rodents including voles, shrews, hamsters, and other members of the family Cricetidae.
The Bruce effect, or pregnancy block, is the tendency for female rodents to terminate their pregnancies following exposure to the scent of an unfamiliar male. The effect was first noted in 1959 by Hilda M. Bruce, and has primarily been studied in laboratory mice. In mice, pregnancy can only be terminated prior to embryo implantation, but other species will interrupt even a late-term pregnancy.
Barbara Hibbs Blake was an American mammalogist and college professor.