This is not a gray-tailed vole, but is a relative--the montane vole (Microtus montanus) is similar in size and appearance, but with grizzled, less yellowish fur.
The population of gray-tailed vole in Washington is unknown. Gray-tailed voles are probably still common in pastures and grassy roadsides in Clark County, but current status and distribution is uncertain; southwestern Clark County is a developing urban/suburban area.
Description and Range
Physical description
The gray-tailed vole is a small mammal in the Cricetidae family. They are 5.5 to 8 inches long; their gray tail is 1.2 to 3 inches long; and they weigh 1.2 to 3 ounces. Males are larger than females. The fur of adults in summer is light yellowish-brown or yellowish-gray on the topside and grayish-white on the underside; in winter, the fur on the back appears darker due to black-tipped hairs. For more details, visit Animal Diversity Web.
Ecology and life history
Gray-tailed voles occur in hayfields, pastures, fallow grassy areas, and grain fields. In Oregon, Gray-tailed voles are associated almost exclusively with agricultural lands, especially grasses grown for seed, small grains, and permanent pastures of legumes and grasses. The species also exists along grassy highway and railroad rights-of-way.
They construct intricate runway and burrow systems Burrows are dug in soil or placed under fallen log debris.
Gray-tailed voles eat a wide variety of green plants, including grasses, sedges, and forbs, such as clover, wild onions, and false dandelion.
Nests are built underground or above ground beneath boards, bales, and debris scattered in fields. Breeding likely takes place throughout the year. Litter size averages about five young. In the lab, females as young as 18 days of age were capable of mating and subsequently produced viable offspring.
This species exhibits extreme population fluctuations like other members of its genus.
Owls, hawks, foxes, skunks, and domestic and feral cats are common predators.
Geographic range
Species distribution is limited to the lower elevations of Clark County, Washington, and the Willamette Valley of Oregon. Populations can be locally abundant. Population status and trends in Clark County are unknown.
For a map of range-wide distribution and conservation status of this species, check out NatureServe Explorer.
Climate vulnerability
Sensitivity to climate change
There is no information on the sensitivity of gray-tailed voles to climate change. However, the species' use of agricultural fields and grassy areas and its high reproductive rate will likely provide some buffering against any climate change impacts.
Exposure to climate change
- None known
Conservation
Conservation Threats and Actions Needed
- Resource information collection needs
- Threat: Lack of data on current status and distribution.
- Action Needed: Determine population status and distribution.
- Threat: Lack of information on current threats.
- Action Needed: Determine threats to the population.
See the Climate vulnerability section for information about the threats posed by climate change to this species.
Resources
References
Johnson, R. E., and K. M. Cassidy. 1997. Mammals of Washington state: location data and modeled distributions. Washington State GAP Analysis, Volume 3. Washington Cooperative Fish and Wildlife Research Unit, Seattle, Washington.
Verts, B. J. and L. N. Carraway. 1998. Land mammals of Oregon. University of California Press, Berkeley, California.
Verts, B. J. and L. N. Carraway. 1987. Microtus canicaudus. Mammalian Species 267:1-4.
Other resources
- University of Michigan – Museum of Zoology - Animal Diversity Web: Gray-tailed Vole
- Burke Museum – Mammals in Washington: Gray-tailed Vole