Southern Red-Backed Vole (Clethrionomys gapperi)

County List:

Rule:

Forested or Mixed Forested/Nonforested Landscapes

      (Any Forested Upland Except Conifer Plantations (Any Size Class))
      or (Any Forested Lowland (Any Size Class))
      or (Conifer Plantations (Regen and Sap))
      or Upland Brush
      or Savanna
      or Lowland Brush
      or Bog
      or Treed Bog
   containing:
      Mast 
      and (Dead Down Woody Debris or Rock)

Habitat List:

view size class definitions

Literature:

The southern red-backed vole inhabits the cool, moist forests of boreal North America. Although coniferous forest are preferred habitat, deciduous or mixed coniferous/deciduous woods are acceptable. It frequents lowland habitats, such as swamps of cedar, spruce, or tamarack, and also lives in upland forests, especially if standing water is nearby. The forest floor in this vole's home is a thick carpet of litter with numerous rotting stumps, exposed roots, and moss-covered logs.

While foraging, it stays close to fallen logs or rocks and frequently travels through underground passages excavated by large shrews or various moles. This vole is a good climber and occasionally forages or nests in trees. When resting, it occupies a spherical nest inside a tree cavity or under a log. The woodland jumping mouse avoids areas where the red-backed vole is abundant.

This species is an opportunistic feeder, changing its diet as the seasons progress. It eats leaf petioles and young shoots in spring, adds fruits and berries in summer, and changes to nuts and seeds in autumn. The subterranean fungus Endogone is a dietary staple during warm-weather months.

Unlike many squirrels and mice, the southern red-backed vole does not commonly cache food for winter use, but it continues to forage for seeds under the snow and supplements this granivorous diet with tree roots and bark when needed. Throughout the year, the red-backed vole obtains added protein by preying on insects, but to a lesser extent than commonly seen in mice.

Habitat: Cool moist deciduous, mixed or coniferous forests among mossy rocks, logs, tree roots, or other cover. Less commonly found near stone walls at woodland edges or near talus slopes. Favors damp situations in coniferous or mixed woods. Highest densities found in subclimax communities. Uses young clearcuts in deciduous or coniferous woodlands and mixed forest.

Special Habitat Requirements: Water sources such as springs, brooks, or bogs, debris cover (fallen trees, stumps, rocks, slash).

Habitat Preferences: The southern red-backed vole inhabits northern forests. The naturalist expects to find them most often in cool, shaded, moist, and mature woodland (mixed hardwoods and conifers) containing scattered shrubs, decaying stumps, exposed tree root systems, logs partly buried in mossy growth, and leaf litter. Successional changes induced by clear-cutting reduce habitat quality, especially food supply, and vole populations tend to decrease in these situations. According to Getz, these rodents display a preference for areas near water (such as swamp borders), although such environments as dry birch woods are also used. In Michigan, these small mammals have been found in virgin hardwood forests in Alger County; cedar swamps in Leelanau County, most forest types, especially conifers, swamps, and bogs in Marquette County; in a root cellar in Alger County; a clearing bordered by a highway and a coniferous swamp in Roscommon County; widespread (except in bogs) in McCormick Forest in Marquette and Baraga counties; lowland conifer associations on Beaver Island; forests, especially hardwoods, in Gogebic and Ontonagon counties; hardwoods in Charlevoix County; and forest swamp in Montmorency County.

Behavior: Southern red-backed voles apparently reappear more slowly than deer mice after fires, perhaps because it may take up to seven years for suitable ground cover to return.

Nests are usually secluded under logs, in stumps, under brush or in clumps of moss. They are occasionally found in tree holes, or in limb crotches as high as 20 ft above ground.

Ecology: C. gapperi frequents chiefly mesic habitats in coniferous, deciduous, and mixed forests with abundant litter of stumps, rotting logs, and exposed roots. In the Midwest, C. gapperi occupies coniferous forests of pine, cedar, spruce, balsam fir, hemlock, and tamarack, deciduous forests of maple, basswood, oak, aspen, and birch, mixed hardwoods, and thick brush. Suitable habitats in eastern United States include forests, cut-over woodlots, forest-edge communities, marsh-grass, stone walls, old fields, and sedge and chelone communities.

The influence of fire on the distribution and abundance of C. gapperi has been studied in forest and oak-savannas. Compared to other small mammals, C. gapperi usually showed a decreased ability to colonized early post-burn communities. Given at lest two growing seasons, C. gapperi may become established in burns as habitat becomes more suitable (i.e. increased food availability and cover). Tester, in contrast, found a greater number of C. gapperi following burning of an oak-savanna community. Immigration of adults occurred soon after the burn, thereby increasing density. Clearcutting resulted in an initial increase in abundance of C. gapperi in clearcuts adjacent to uncut stands. Lovejoy found an increase in density of red-backed voles following logging of dry areas; however; minimal change occurred in numbers after logging of moist sites in a northern hardwood forest of New Hampshire. Powell noted a higher density of C. gapperi where a tornado had blown down trees than in an adjacent standing forest.

The redback vole avoided fields, forest clearings, and other non-forested situations in northern Vermont; it was abundant in most forest types. Within northern forested areas the abundance of the redback vole was related primarily to the abundance of debris cover (fallen trees and limbs, stumps, brush piles, and boulders). Microclimatic differences between non-forested and forested sites were not sufficient to influence the local distribution of the redback vole, nor did they influence the distribution of voles within different forested types with variable vegetational cover. Further south (Connecticut), the redback vole was restricted primarily to low swampy areas; water availability is too low in upland sites for the vole to maintain a proper water balance. Microclimate was not a factor in the restriction of the redback vole to swamps in southern regions, or in the differential distribution pattern within swamps. Within swamps the abundance of vole was positively correlated with the amount of debris cover present. The redback vole appears to be more abundant in areas with greater debris cover owing to increased protection from predation; presence of snow cover did not appear to be a significant factor influencing the local distribution of the redback vole in either region.