Microtus xanthognathustaiga vole

Last updated:

Geographic Range

Taiga voles, Microtus xanthognathus, are found in scattered locations throughout the boreal taiga zone. Populations are found from the west coast of Hudson Bay to the interior of Alaska. There are records of taiga voles in Manitoba, Alberta, the Northwest Territories, the Yukon Territory, and Alaska. (Conroy and Cook, 1999)

Habitat

Taiga voles inhabit quite a wide range of microhabitats within the taiga community. These include mixed woods bordering a marsh, the banks of rivers, wet grassy swamps, and open black spruce forests with sphagnum moss for ground cover. It seems that the ideal habitat for these voles is moist, highly productive forest in the early successional stages. They also seem to prefer recently burned areas and black spruce forests. (Conroy and Cook, 1999; Wolff and Lidicker, 1980)

There seem to be two habitat conditions that taiga voles look for when establishing residency in an area. One is rhizomes, which provide winter food. These require moist conditions for Equisetum or Epilobium growth. The other factor important to these voles in habitat selection is good burrowing conditions. These can be found in areas with moss for ground cover. Both of these conditions seem to point to a habitat similar to the ideal habitat mentioned earlier. (Conroy and Cook, 1999; Wolff and Lidicker, 1980)

  • Terrestrial Biomes
  • taiga

Physical Description

Microtus xanthognathus is one of the largest voles in the genus. These animals weigh between 140 and 160 grams, and have an overall length of 186 to 226 mm. The tail is bicolored, with a blackish top and a dusky gray underside, and is 45 to 53 mm in length. The pelage is sepia to bister in color on the upper parts, with coarse black hairs on the back. On the sides of the nose, by the whiskers, and in the ear patches, M. xanthognathus has a rusty-yellowish coloration. The underside is dusky gray. These voles have 16 teeth, four of which are incisors and 12 are molars. They lacks canines and premolars. (Conroy and Cook, 1999)

  • Sexual Dimorphism
  • sexes alike
  • Range mass
    140 to 160 g
    4.93 to 5.64 oz
  • Range length
    186 to 226 mm
    7.32 to 8.90 in
  • Average basal metabolic rate
    1.44 ± 0.089 cm3.O2/g/hr

Reproduction

Taiga voles are polygynous, and males may use resource-defense as a means of attracting mates. Males also are quite territorial during the mating season. (Conroy and Cook, 1999)

Taiga voles breed from early in May to September. In Alaska the first pregnancies happen around the time of snow melt. Young are not sexually mature during their first season and cannot breed. (Conroy and Cook, 1999; Wolff and Lidicker, 1980)

Males reach sexual competance two weeks prior to the first estrus in females. Their seminal vesicles reach maximum length between two weeks and a month after the decline in testis size. (Conroy and Cook, 1999; Wolff and Lidicker, 1980)

Litter size is between six and thirteen young with an average of 8.8. Usually the first litter is smaller than the second in a year. Females only have two litters in their lifetime. (Conroy and Cook, 1999; Wolff and Lidicker, 1980)

Although information is lacking for M. xanthognathus, the gestation period for other members of the genus has been recorded at between 19 and 25 days. It is likely that this species is similar. (Nowak, 1999)

Newborn voles typically weigh around 2.1 g. They are altricial, and are cared for in the nest by their mother until they are able to forage for themselves. Newborn voles do not open their eyes until they are around 9 days of age. Weaning may occur by as early as 12 days. Although there are no data available for M. xanthognathus, it is likely that they are similar to other members of their genus. (Nowak, 1999)

  • Breeding interval
    These voles may breed twice a year.
  • Breeding season
    Breeding occurs between May and September.
  • Range number of offspring
    6 to 13
  • Average number of offspring
    8.8

Females appear to give all the parental care. The young are altricial, and must be cared for in a nest until they are able to venture out on their own. Although this happens quite quickly in most species of voles, these boreal animals do not reach reproductive maturity as quickly as most of their congeners, who may breed by the time they are a month old. It is not known if the young of M. xanthognathus stay in the nest longer than do the young of these other species of Microtus. (Nowak, 1999; Wolff, 1980)

  • Parental Investment
  • no parental involvement
  • altricial
  • pre-fertilization
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • female
  • pre-independence
    • protecting
      • female

Lifespan/Longevity

Taiga voles usually live 16 to 18 months if they survive and enter their first winter. (Wolff and Lidicker, 1980)

  • Typical lifespan
    Status: wild
    16 to 18 months

Behavior

Taiga voles nest in groups of five to ten in the winter, which seems to be an adaptation for behavioral thermoregulation. These groups don't seem to be comprized of family members, and are made up of different sexes and ages. (Conroy and Cook, 1999; Wolff and Lidicker, 1980; Wolff and Lidicker, 1981)

Nests have multiple entrances and burrow systems that are branched making them complex. Burrows, nests, and caches are usually found where a layer of litter and moss meets the soil, and a gap can easily be made. The nests of taiga voles are about 30 centimeters under ground, and made of dry grass. In the winter the nests are about 25 to 30 centimeters in diameter, whereas the summer nests are only 15 centimeters in diameter. These temperature inside these nests in the winter stay between 4° and 7° Celsius, even though the air temperatures range between -5° and -23° Celsius and ground temperatures are between -3° and -5° Celsius. This suggests that the nest is never completely empty during the winter. (Conroy and Cook, 1999; Wolff and Lidicker, 1980; Wolff and Lidicker, 1981)

Microtus xanthognathus builds and maintains complex runways that may be partially under ground and are often near water. The voles are not afraid to cross water. (Conroy and Cook, 1999; Wolff and Lidicker, 1980; Wolff and Lidicker, 1981)

Females are territorial around the nest during the mating season. Males also are aggressive and territorial during the mating season. (Conroy and Cook, 1999; Wolff and Lidicker, 1980; Wolff and Lidicker, 1981)

Dispersal occurs periodically during the year, and allows mixing of the population. Late in the summer after breeding is one time when M. xanthognathus disperse. In this round of dispersal, most emigrants are juvenile males. The other time of dispersal is just prior to snowmelt. (Conroy and Cook, 1999; Wolff and Lidicker, 1980; Wolff and Lidicker, 1981)

Home Range

The home range size has not been reported for this species.

Communication and Perception

Taiga voles communicate through scent markings and calls. The scent glands are found in adult males and females and vary in size according to body size. These scent glands increase in size in the early spring and stay enlarged until fall, when they regress in size. (Conroy and Cook, 1999; Wolff and Johnson, 1979; Wolff, 1980)

The scent glands located on the flank may be used in scent marking for individual recognition especially in the context of marking territory. During courtship, males and females sniff each other's flank and anal glands to determine reproductive condition. M. xanthognathus may help to stimulate scent excretion by scratching the flank gland. The oily secretion is known to mat down the hair. (Conroy and Cook, 1999; Wolff and Johnson, 1979; Wolff, 1980)

Besides scent marking, taiga voles also communicate with alarm calls. They give out these alarm calls as a predator enters within an individual's home range, and will continue the call until the predator is within 5 to 8 meters of the individual. These alarm calls are usually not given unless an individual is in safe territory. It is not known if the voles are assisting kin when making these alarm calls, warning the predators off, or are involved in some sort of reciprocal altruism with neighboring voles. (Conroy and Cook, 1999)

Although not specifically reported, it is likely that these voles use tactile and visual signals in their communications, also. Tactile communication is important in fighting, mating, and nurturing the young in just about all mammals.

Food Habits

Taiga voles eat a variety of different plants. They prefer to eat grasses, like Calamagrostis, rhizomes, and berries in the summer. Then as these summer foods start to die off, they switch over to stored rhizomes, particularly the ones from Equisetum, which make up the majority of their winter diet. Ninety percent of their winter food is from these rhizomes and the other ten percent is from eating food away from the nest. The voles gather rhizomes and store them from mid-August to mid-September. (Wolff and Lidicker, 1980; Wolff and Lidicker, 1981)

  • Plant Foods
  • leaves
  • roots and tubers
  • seeds, grains, and nuts
  • Other Foods
  • fungus

Predation

Taiga voles are prey for a number of raptors and carnivores. To avoid predators they give out alarm calls and will continue this call until the predator is within 5 to 8 meters of the individual. (Conroy and Cook, 1999)

Ecosystem Roles

These voles serve as a food source for many animals. Microtus pennsylvanicus also has been reported to use the same runways as taiga voles. Because of their food caching behavior, these voles may play some role in seed dispersal. (Conroy and Cook, 1999; Wolff and Lidicker, 1980)

  • Ecosystem Impact
  • disperses seeds

Economic Importance for Humans: Positive

These is no apparent direct benefit of this species to humans.

Economic Importance for Humans: Negative

There is no reported negative effect of these voles on humans.

Conservation Status

The taiga vole is not listed by CITES or IUCN. (Conroy and Cook, 1999)

Other Comments

Other common name by which this species is known include yellow-cheeked vole, yellow-nosed vole, yellow-snouted vole, chestnut-cheeked vole, and fulvous-cheeked vole. (Conroy and Cook, 1999)

Contributors

Nancy Shefferly (editor), Animal Diversity Web.

Eric Kroening (author), University of Wisconsin-Stevens Point, Chris Yahnke (editor), University of Wisconsin-Stevens Point.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

acoustic

uses sound to communicate

altricial

young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

folivore

an animal that mainly eats leaves.

fossorial

Referring to a burrowing life-style or behavior, specialized for digging or burrowing.

herbivore

An animal that eats mainly plants or parts of plants.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

motile

having the capacity to move from one place to another.

mycophage

an animal that mainly eats fungus

native range

the area in which the animal is naturally found, the region in which it is endemic.

polygynous

having more than one female as a mate at one time

scent marks

communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

social

associates with others of its species; forms social groups.

solitary

lives alone

stores or caches food

places a food item in a special place to be eaten later. Also called "hoarding"

tactile

uses touch to communicate

taiga

Coniferous or boreal forest, located in a band across northern North America, Europe, and Asia. This terrestrial biome also occurs at high elevations. Long, cold winters and short, wet summers. Few species of trees are present; these are primarily conifers that grow in dense stands with little undergrowth. Some deciduous trees also may be present.

terrestrial

Living on the ground.

visual

uses sight to communicate

References

Conroy, C., J. Cook. 1999. Microtus xanthognathus. Mammalian Species, 627: 1-5.

Nowak, R. 1999. Walker's Mammals of the World, Sixth Edition. Baltimore and London: The Johns Hopkins University Press.

Wolff, J. 1980. Social Organization of the Taiga Vole (Microtus xanthognathus). Biologist, 62 (1-4): 34-45.

Wolff, J., M. Johnson. 1979. Scent Marking in Taiga Voles, Microtus xanthognathus. Journal of Mammalogy, 60 (2): 400-404.

Wolff, J., W. Lidicker. 1981. Communal Winter Nesting and Food Sharing in Taiga Voles. Behavioral Ecology and Sociobiology, 9 (4): 237-240.

Wolff, J., W. Lidicker. 1980. Population Ecology of the Taiga Vole, Microtus xanthognathus, in Interior Alaska. Canadian Journal of Zoology, 58(10): 1800-1812.