Articles on this page are available in 1 other language: Spanish (3) (learn more)

Overview

Brief Summary

Description

"Townsend's Vole is one of the largest voles in North America, and it is also very abundant where it occurs, making the species highly significant to a multitude of predators, including herons, owls, and other birds of prey; and raccoons, skunks, weasels, mink, coyotes, bobcats, and red and gray foxes. Snakes, too, feed on these Voles. Densities as high as 800 Voles per hectare have been recorded, and when densities exceed 100, Townsend's Vole may exclude other small rodents from its range through competition. Townsend's Vole has dark-brownish fur and ears large enough to project above the fur. The ears are small by most standards but large for the genus: Microtus comes from two Greek words that mean ""small ear."""

Links:
Mammal Species of the World
Click here for The American Society of Mammalogists species account
  • Original description: Bachman, J., 1839.  Description of several new species of American quadrupeds, p. 60.  Journal of the Academy of Natural Sciences of Philadelphia, Part 1, 8:57-74.
Creative Commons Attribution 3.0 (CC BY 3.0)

© Smithsonian Institution

Source: Smithsonian's North American Mammals

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Distribution

Range Description

This species ranges from Triangle Island, British Columbia in Canada, south to Humbolt Bay, California in the United States; east in British Columbia to Chilliwack; in Washington to Sauk, Nisqually Flats, and Clark County; in Oregon to Salem, Eugene, and Prospect. It occurs from sea level to about 1,830 m asl in Olympic Mountains, to about 915 m asl in Cascades, Oregon.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

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

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

National Distribution

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

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Global Range: Triangle Island, British Columbia, south to Humbolt Bay, California; east in British Columbia to Chilliwack; in Washington to Sauk, Nisqually Flats, and Clark County; in Oregon to Salem, Eugene, and Prospect. Sea level to about 1830 m in Olympic Mountains, to about 915 m in Cascades, Oregon.

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Physical Description

Size

Length: 24 cm

Weight: 103 grams

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Size in North America

Length:
Range: 169-225 mm

Weight:
Range: 47-83 g
Creative Commons Attribution 3.0 (CC BY 3.0)

© Smithsonian Institution

Source: Smithsonian's North American Mammals

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Ecology

Habitat

Habitat and Ecology

Habitat and Ecology
It occupies a variety of habitats, but typically occurs in salt and fresh marshes, moist meadows (sometimes dry grass), wetlands along streams; alpine and subalpine meadows. Constructs extensive underground burrow systems and runways through grass. Burrow entrance may be underwater.

Nests may be on or below soil surface. The length of breeding season depends on stage in multiannual abundance cycle. Gestation lasts 21-24 days. Litter size averages 4-7 in different areas. In captivity, young are weaned at 15-17 days, first estrus at 35-80 days (Cornely and Verts 1988). Diet includes various kinds of green vegetation; grasses, sedges, and forbs, mint bulbs.

Systems
  • Terrestrial
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Comments: Salt and fresh marshes, moist meadows (sometimes dry grass), wetlands along streams; alpine and subalpine meadows. Constructs extensive underground burrow systems and runways through grass. Burrow entrance may be underwater. Nests may be on or below soil surface.

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Migration

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.

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Trophic Strategy

Comments: Eats various kinds of green vegetation; grasses, sedges, and forbs, mint (MENTHA) bulbs.

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

General Ecology

Density up to several hundred per ha during population peaks.

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Life History and Behavior

Cyclicity

Comments: Active throughout the year.

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Reproduction

Length of breeding season depends on stage in multiannual abundance cycle. Gestation lasts 21-24 days. Litter size averages 4-7 in different areas. In captivity, young are weaned at 15-17 days, first estrus at 35-80 days (Cornely and Verts 1988).

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Conservation

Conservation Status

IUCN Red List Assessment


Red List Category
LC
Least Concern

Red List Criteria

Version
3.1

Year Assessed
2008

Assessor/s
Linzey, A.V. & NatureServe (Hammerson, G.)

Reviewer/s
Amori, G. (Small Nonvolant Mammal Red List Authority) & Chanson, J. (Global Mammal Assessment Team)

Contributor/s

Justification
Listed as Least Concern because it has a very wide range, there are no major threats, it can be very common, and its population is not thought to be in decline.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

National NatureServe Conservation Status

Canada

Rounded National Status Rank: N5 - Secure

United States

Rounded National Status Rank: N5 - Secure

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

NatureServe Conservation Status

Rounded Global Status Rank: G5 - Secure

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Status

The parent species and one subspecies (M. townsendii pugeti, the Shaw Island vole) are Near Threatened.
Creative Commons Attribution 3.0 (CC BY 3.0)

© Smithsonian Institution

Source: Smithsonian's North American Mammals

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Population

Population
Densities as high as 800 per hectare have been recorded, but populations fluctuate widely.

Population Trend
Stable
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Threats

Major Threats
There are no major threats to this species.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Management

Conservation Actions

Conservation Actions
This species is not of conservation concern and its range includes several protected areas.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© International Union for Conservation of Nature and Natural Resources

Source: IUCN

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Wikipedia

Townsend's vole

Townsend's vole (Microtus townsendii) is a species of rodent in the family Cricetidae, the sister species of M. canicaudus.[3] It is found in temperate grasslands of British Columbia in Canada and in the states of Washington and Oregon in the United States.[1][4]

Greek root words for "small ear" are the source for the genus name Microtus.[4] American naturalist and writer John Kirk Townsend collected the type specimen in 1835, which accounts for the second part of the name.[5][6]

Description[edit]

Townsend's vole is one of the largest voles in North America,[7] growing to a total length of 169 to 225 mm (6.7 to 8.9 in) including a tail of 48 to 70 mm (1.9 to 2.8 in), and a weight of 48 to 73 g (1.7 to 2.6 oz).[2][3][8] The ears are wide and prominent, being clearly visible above the fur, which is thin and coarse. The upper surface is dark brown with many guard hairs with black tips and the underparts are paler. The feet are slate grey and the tail is blackish above and dark brown beneath. Juveniles are generally darker than adults with dark grey underparts and black tails and feet.[5]

Distribution and habitat[edit]

Townsend's vole is found in the extreme west of North America. Its range extends from Vancouver Island, British Columbia southwards through Washington state and Oregon to Humboldt Bay in California. It occurs from sea level to altitudes of 1,830 m (6,000 ft) in the Olympic Mountains and 915 m (3,002 ft) in the Cascade Range.[1] These voles typically live in wet meadows, marshes, flood plains, wet areas with rank vegetation and salt marshes.[5]

The population can become extremely dense, so that it impacts or excludes other species. Their proliferation rate makes them a good source of food for many species.[4]

Biology[edit]

Townsend's vole lives in a burrow system and creates runways among the vegetation in its habitat. The runways are used all year round by successive generations of voles and may be 2.5 to 5 cm (1 to 2 in) deep.[5] In the summer the voles may take advantage of the denser cover available and also move about elsewhere. Feces are deposited in the runways and large latrines may form, often at intersections.[5] These latrines have been reported as reaching dimensions of 18 by 8 cm (7 by 3 in) with a height of up to 13 cm (5 in). Nests may be built on the surface of the ground or on hummocks, and this allows the vole to live in seasonally-flooded areas where its burrows are sometimes underwater. Both underground and surface nests are made of grasses.[5]

Townsend's vole feeds on soft green plant material such as rushes, tules, grasses, sedges, horsetails, clovers, alfalfa, blue-eyed grass and purple-eyed grass. They also store the bulbous roots of American wild mint, consuming them during the winter even though plenty of succulent green food is available at that time.[5]

Breeding takes place between February and October. The gestation period is about 23 days and the litter size ranges from one to nine young with an average of four, larger females usually having larger litters. The offspring are weaned at about sixteen days of age.[5]

Status[edit]

Townsend's vole has a wide range and undergoes large swings in population. Over the long term, the population seems to be steady and in some localities this vole is very plentiful, having been recorded at densities as high as eight hundred individuals per hectare.[4] No particular threats to this species have been recognised; the International Union for Conservation of Nature assessed its conservation status as being of "least concern".[1]

References[edit]

Citations[edit]

  1. ^ a b c d Linzey, A.V. & NatureServe (Hammerson, G.) (2008). "Microtus townsendii". IUCN Red List of Threatened Species. Version 2014.2. International Union for Conservation of Nature. Retrieved 2014-10-25. 
  2. ^ a b Bachman 1839.
  3. ^ a b c Wilson & Reeder 2005.
  4. ^ a b c d Microtus townsendii Townsend's Vole. Smithsonian National Museum of Natural History. Retrieved October 21, 2014. 
  5. ^ a b c d e f g h Cornely & Verts 1988, pp. 1–9.
  6. ^ Beolens, B.; Watkins, M.; Grayson, M. (2009-09-28). The Eponym Dictionary of Mammals. The Johns Hopkins University Press. p. 416. ISBN 978-0801893049. OCLC 270129903. 
  7. ^ "Townsend's Vole Microtus townsendii". enature.com. Retrieved October 21, 2014. 
  8. ^ Kays & Wilson 2010, p. 134.

Sources[edit]

Further reading[edit]

Creative Commons Attribution Share Alike 3.0 (CC BY-SA 3.0)

Source: Wikipedia

Unreviewed

Article rating from 0 people

Default rating: 2.5 of 5

Disclaimer

EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.

To request an improvement, please leave a comment on the page. Thank you!