|Scientific Name:||Microtus ochrogaster (Wagner, 1842)|
|Taxonomic Notes:||Includes M. o. ludovicianus, an isolated (and apparently extinct) form previously regarded as a distinct species. Subspecies minor exhibits strong morphometric segregation from other M. ochrogaster and merits further examination of its taxonomic status (Musser and Carleton, in Wilson and Reeder 1993, 2005).|
|Red List Category & Criteria:||Least Concern ver 3.1|
|Contributor(s):||Hammerson, G.A. & Linzey, A.|
Listed as Least Concern because it is very widespread, common throughout the heart of its range, there are no major threats and it occurs in many protected areas.
|Previously published Red List assessments:|
|Range Description:||This species ranges throughout the prairie states of the United States and northward into the south-central provinces of Canada. It occurs in east-central Alberta, central Saskatchewan, and southern Manitoba south through northern Oklahoma and Arkansas, east to Ohio, West Virginia, Kentucky, central Tennessee, and westernmost Virginia; relictual populations occur in central Colorado, northern New Mexico, and (formerly) southwestern Louisiana and adjacent Texas (Musser and Carleton, in Wilson and Reeder 1993). The disjunct subspecies (M. o. ludovicianus), previously found in east Texas and western Louisiana, is apparently extinct.|
Native:Canada (Alberta, Manitoba, Saskatchewan); United States (Alabama, Arkansas, Colorado, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana - Regionally Extinct, Michigan, Minnesota, Missouri, Montana, Nebraska, New Mexico, North Dakota, Ohio, Oklahoma, South Dakota, Tennessee, Texas, West Virginia, Wisconsin, Wyoming)
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||This species is considered secure within its range (NatureServe). Periodic high densities may occur every two to four years (perhaps every two years in Oklahoma, where heavy grazing by cattle reduces grass cover and dampens multiyear cycles, Caire et al. 1989). However, some researchers believe that distinct multiannual cycles are not characteristic of this species (see Stalling 1990). Average of 25 per hectare; may surpass 250 per hectare in peak years (Krebs et al. 1969); peaks of greater than 600 per hectare and 1,060 per hectare have been reported (see Stalling 1990).|
|Current Population Trend:||Stable|
|Habitat and Ecology:||These voles occur in a variety of prairie habitats, as well as upland agricultural habitats. They will inhabit herbaceous fields; grasslands, old agricultural lands and thickets; places where there is suitable cover for runways. Also reported from jackpine woods. Habitats include Andropogon-poa pratensis meadows in Kansas, <Artemisia-grass in Wyoming, Festuca-dactylis grasslands in Indiana. Floodplains of rivers serve as dispersal routes in the Southwest. Railroad and highway right-of-ways may serve as corridors for dispersal throughout the range. |
Nests are placed in burrows, under boards or logs, and above ground in grassy clumps. It may build winter nests in old anthills. Prairie voles breed year-round, especially spring/fall; peaks in reproduction depend on the availability of moisture. Gestation lasts 20-23 days. There are several litters per year; and one to seven (average three to four) young per litter; litter size varies with season and female size and age. Both parents (and sometimes older siblings) tend neonates. They sexually mature generally by about five to six weeks.
There are three types of social groups: male-female pair, single female, and communal groups of 2-21 individuals (due primarily to increased survival of philopatric juveniles in late fall). Annual home range is rarely more than 1,000 square metres; averages a few hundred square metres. Lifespan generally is one year or less. Most remain at the natal nest until death; those that do disperse leave home at about six to eight weeks and move short distances (e.g., 28 to 30 m; McGuire et al. 1993). Getz (1997) found strong natal philopatry in a low-food habitat in Illinois.
Diet consists almost entirely of vegetation (grasses, forbs) and some insects. Underground tunnel systems frequently are used for feeding on roots. Active both day and night, year-round. Peak activity probably occurs near dusk/dawn. Diurnal activity decreases in summer; nocturnal activity decreases in winter. Prairie voles are important prey species for many predators.
|Generation Length (years):||1-2|
|Major Threat(s):||There are no major threats to the species across its entire range. Destruction of grasslands for agricultural purposes has greatly reduced the extent of suitable habitat (Caire et al. 1989). On the other hand, clearing of forests has allowed an increase in distribution and abundance along the eastern margin of its range. In Kansas, it has moved out of areas subjected to experimental prairie fire (Clark and Kaufman 1990).|
|Conservation Actions:||This species is not of conservation concern and its range includes many protected areas.|
|Errata reason:||This errata assessment has been created because the map was accidentally left out of the version published previously.|
|Citation:||Cassola, F. 2016. Microtus ochrogaster. (errata version published in 2017) The IUCN Red List of Threatened Species 2016: e.T42631A115196932.Downloaded on 17 December 2017.|