Microtus pinetorumwoodland vole

Geographic Range

Woodland voles, Microtus pinetorum, are found from central Texas to Wisconsin, and eastward to the Atlantic coast (excluding Florida).

Habitat

Woodland voles live in deciduous forests in eastern North America. They are surface burrowers, moving through thick leafmold and loose soil.

Physical Description

Woodland voles have a combined head and body length between 83 and 120 mm; the tail ranges from 15 to 40 mm in length. They weigh between 14 and 37 g. There is almost no sexual dimorphism within the species. The dorsal region varies from light to dark brown in color. The ventral surface is whitish or silvery. Their bodies have become modified for their partially subterranean habitat by a reduction of the eyes, external ears, and tail. Their foreclaws are also somewhat enlarged for digging.

  • Sexual Dimorphism
  • sexes alike
  • Range mass
    14 to 37 g
    0.49 to 1.30 oz
  • Range length
    83 to 120 mm
    3.27 to 4.72 in
  • Average basal metabolic rate
    0.305 W
    AnAge

Reproduction

Woodland voles have a monogamous mating system.

Mating generally takes place from spring through fall with a peak in late spring to early summer. Some woodland voles may breed throughout the year if they live at low altitudes or experience mild winters. After a gestation period of about 21 days, females give birth to a litter of on average 3 to 7 individuals, though litters can range from 1 to 13 newborns. Females are polyestrous and may have several litters in a year.

  • Breeding interval
    Woodland voles may breed several times a year.
  • Breeding season
    Mating generally takes place from spring through fall with a peak in late spring to early summer.
  • Range number of offspring
    1 to 13
  • Average number of offspring
    3 to 7
  • Average number of offspring
    3
    AnAge
  • Average gestation period
    21 days
    AnAge
  • Average weaning age
    17 days
  • Average age at sexual or reproductive maturity (female)
    Sex: female
    98 days
    AnAge

Females make nests in underground burrows, shallow surface depressions, or under rocks and logs. Nests are globular in shape and lined with shredded vegetation. They are approximately 150 mm in diameter. Young are helpless at birth and are weaned in about 17 days.

  • Parental Investment
  • altricial
  • pre-fertilization
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • female

Lifespan/Longevity

On average, woodland voles live less than three months. The longest known lifespan in the wild is just over a year. (Kurta, 1995)

Behavior

Woodland voles are surface burrowers, normally going no deeper than 100 mm below ground. They may also use the burrows of mice, moles, and large shrews. They are active at any time of the night or day. There seems to be strong sociality between males and females, and they are usually bonded in monogamous male-female pairs. (Kurta, 1995)

  • Range territory size
    700 to 2800 m^2

Home Range

Woodland voles spend their entire lives within the same home range of 700 to 2800 square meters. (Kurta, 1995)

Communication and Perception

When sensing danger or when surprised, woodland voles make a high pitched noise that may serve as a warning signal. They have small eyes, so they probably do not rely much on their vision, and instead rely on their senses of touch, smell, and hearing to locate one another and find food.

Food Habits

Woodland voles are mostly herbivorous animals that feed on tubers, roots, seeds, leaves, and nuts. They may also eat berries and insects. In the fall, woodland voles cache tubers and shoots inside of a burrow to eat in times of winter shortage. (Kurta, 1995)

  • Animal Foods
  • insects
  • Plant Foods
  • leaves
  • roots and tubers
  • seeds, grains, and nuts
  • fruit

Predation

Woodland voles have numerous predators, including hawks, owls, snakes, foxes, raccoons, weasels, skunks, and opossums. (Kurta, 1995)

Ecosystem Roles

Woodland voles may disperse seeds and they are an important food source for numerous predators.

Economic Importance for Humans: Positive

There are no known direct positive effects of woodland voles on humans. Because they are important prey for many species, they help maintain a thriving ecosystem.

Economic Importance for Humans: Negative

During a severe winter M. pinetorum may cause damage to trees. In orchards these animals may strip the bark from the roots and lower trunks of fruit trees.

  • Negative Impacts
  • crop pest

Conservation Status

Some populations at the periphery of the range of this species are considered to be threatened or--as is the case in Michigan--of "special concern." However, woodland voles are common throughout most of their range and sometimes considered agricultural pests.

Other Comments

Voles are often confused with moles due to similarity of appearance and behavior.

Contributors

Tanya Dewey (editor), University of Michigan-Ann Arbor, George Hammond (editor), Animal Diversity Web Staff.

Allison Poor (editor), University of Michigan-Ann Arbor.

David Copp (author), University of Michigan-Ann Arbor.

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

diurnal
  1. active during the day, 2. lasting for one day.
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.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

fossorial

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

granivore

an animal that mainly eats seeds

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).

monogamous

Having one mate at a time.

motile

having the capacity to move from one place to another.

native range

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

nocturnal

active during the night

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.

stores or caches food

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

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

visual

uses sight to communicate

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

References

Walker, Ernest P. Mammals of the World [volume III, ps. 647 - 1500]. Johns Hopkins Press: Baltimore, 1964.

I.M. Gromov & I.Y. Polyakov. Voles (Microtinae). Ed. Robert S. Hoffman & Douglas Siegel-Causey. Smithsonian Institute Libraries: Washington D.C., 1992.

Nowak, Ronald M. Walker's Mammals of the World [fifth edition, volume III]. Johns Hopkins University Press: Baltimore, 1991.

"Animal Life Histories Database" (On-line).

Kurta, A. 1995. Mammals of the Great Lakes Region. Ann Arbor: The University of Michigan Press.

Ruff, S., D. Wilson. 1999. The Smithsonian Book of North American Mammals. Washington [D.C.]: Smithsonian Institution Press in association with the American Society of Mammalogists.