Vagrant Shrew - Sorex vagrans
(see State Rank Reason below)
State Rank Reason (see State Rank above)
Species is relatively common within suitable habitat and widely distributed across portions of the state
- Details on Status Ranking and Review
ScoreG - 200,000-2,500,000 km squared (about 80,000-1,000,000 square miles)
Comment245,660 square Kilometers from Natural Heritage Program range maps
ScoreE - Relatively Stable (±25% change)
CommentHabitat is unlike to have increased or decreased more than 25% since European arrival
ScoreE - Stable. Population, range, area occupied, and/or number or condition of occurrences unchanged or remaining within ±10% fluctuation
CommentSpecies has been frequently captured during structured surveys in the 1990s and 2000s, population appears stable
ScoreH - Unthreatened. Threats if any, when considered in comparison with natural fluctuation and change, are minimal or very localized, not leading to significant loss or degradation of populations or area even over a few decades’ time. (Severity, scope, and/or immediacy of threat considered Insignificant.)
CommentNo threats identified
ScoreC - Not Intrinsically Vulnerable. Species matures quickly, reproduces frequently, and/or has high fecundity such that populations recover quickly (< 5 years or 2 generations) from decreases in abundance; or species has high dispersal capability such that extirpated populations soon become reestablished through natural recolonization (unaided by humans).
CommentHigh fecundity and low age of maturation
ScoreC - Moderate. Generalist. Broad-scale or diverse (general) habitat(s) or other abiotic and/or biotic factors are used or required by the species but some key requirements are scarce in the generalized range of the species within the area of interest.
Raw Conservation Status Score
3.5 + 0 (geographic distribution) + 0 (environmental specificity) + 0 (short-term trend) + 1 (threats) = 4.5
Pacific coast: tine present on anteriomedial edge of I1; tail distinctly bicolored in young, indistinctly bicolored in adults; never more than 4 pairs of friction pads on the second to fourth digits of hind feet; level of pigmentation at or below level of median tine on I1; body size small to medium; U5 triangular, body of U1s not touching, P4 overlapping U5; zygomatic process of maxillary pointed (Carraway 1990).
See Carraway (1995) for a key to western North American soricids based primarily on dentaries.
Western Hemisphere Range
Observations in Montana Natural Heritage Program Database
Number of Observations:
(Click on the following maps and charts to see full sized version)
Map Help and Descriptions
(Observations spanning multiple months or years are excluded from time charts)
At elevations below 5000 ft, usually Douglas-fir, lodgepole pine, western larch, grand fir, western red cedar forests (Hennings and Hoffmann 1977). Often found in moist sites (Hoffmann and Pattie 1968).
Ecological Systems Associated with this Species
- Details on Creation and Suggested Uses and Limitations
How Associations Were Made
We associated the use and habitat quality (common or occasional) of each of the 82 ecological systems mapped in Montana for
vertebrate animal species that regularly breed, overwinter, or migrate through the state by:
- Using personal observations and reviewing literature that summarize the breeding, overwintering, or migratory habitat requirements of each species (Dobkin 1992, Hart et al. 1998, Hutto and Young 1999, Maxell 2000, Foresman 2012, Adams 2003, and Werner et al. 2004);
- Evaluating structural characteristics and distribution of each ecological system relative to the species' range and habitat requirements;
- Examining the observation records for each species in the state-wide point observation database associated with each ecological system;
- Calculating the percentage of observations associated with each ecological system relative to the percent of Montana covered by each ecological system to get a measure of "observations versus availability of habitat".
Species that breed in Montana were only evaluated for breeding habitat use, species that only overwinter in Montana were only evaluated for overwintering habitat use, and species that only migrate through Montana were only evaluated for migratory habitat use.
In general, species were listed as associated with an ecological system if structural characteristics of used habitat documented in the literature were present in the ecological system or large numbers of point observations were associated with the ecological system.
However, species were not listed as associated with an ecological system if there was no support in the literature for use of structural characteristics in an ecological system, even if
point observations were associated with that system.
Common versus occasional association with an ecological system was assigned based on the degree to which the structural characteristics of an ecological system matched the preferred structural habitat characteristics for each species as represented in scientific literature.
The percentage of observations associated with each ecological system relative to the percent of Montana covered by each ecological system was also used to guide assignment of common versus occasional association.
If you have any questions or comments on species associations with ecological systems, please contact the Montana Natural Heritage Program's Senior Zoologist.
Suggested Uses and Limitations
Species associations with ecological systems should be used to generate potential lists of species that may occupy broader landscapes for the purposes of landscape-level planning.
These potential lists of species should not be used in place of documented occurrences of species (this information can be requested at: mtnhp.org/requests
) or systematic surveys for species and evaluations of habitat at a local site level by trained biologists.
Users of this information should be aware that the land cover data used to generate species associations is based on imagery from the late 1990s and early 2000s and was only intended to be used at broader landscape scales.
Land cover mapping accuracy is particularly problematic when the systems occur as small patches or where the land cover types have been altered over the past decade.
Thus, particular caution should be used when using the associations in assessments of smaller areas (e.g., evaluations of public land survey sections).
Finally, although a species may be associated with a particular ecological system within its known geographic range, portions of that ecological system may occur outside of the species' known geographic range.
- Adams, R.A. 2003. Bats of the Rocky Mountain West; natural history, ecology, and conservation. Boulder, CO: University Press of Colorado. 289 p.
- Dobkin, D. S. 1992. Neotropical migrant land birds in the Northern Rockies and Great Plains. USDA Forest Service, Northern Region. Publication No. R1-93-34. Missoula, MT.
- Foresman, K.R. 2012. Mammals of Montana. Second edition. Mountain Press Publishing, Missoula, Montana. 429 pp.
- Hart, M.M., W.A. Williams, P.C. Thornton, K.P. McLaughlin, C.M. Tobalske, B.A. Maxell, D.P. Hendricks, C.R. Peterson, and R.L. Redmond. 1998. Montana atlas of terrestrial vertebrates. Montana Cooperative Wildlife Research Unit, University of Montana, Missoula, MT. 1302 p.
- Hutto, R.L. and J.S. Young. 1999. Habitat relationships of landbirds in the Northern Region, USDA Forest Service, Rocky Mountain Research Station RMRS-GTR-32. 72 p.
- Maxell, B.A. 2000. Management of Montana's amphibians: a review of factors that may present a risk to population viability and accounts on the identification, distribution, taxonomy, habitat use, natural history, and the status and conservation of individual species. Report to U.S. Forest Service Region 1. Missoula, MT: Wildlife Biology Program, University of Montana. 161 p.
- Werner, J.K., B.A. Maxell, P. Hendricks, and D. Flath. 2004. Amphibians and reptiles of Montana. Missoula, MT: Mountain Press Publishing Company. 262 p.
- Commonly Associated with these Ecological Systems
Forest and Woodland Systems
Human Land Use
Recently Disturbed or Modified
Shrubland, Steppe and Savanna Systems
Wetland and Riparian Systems
- Occasionally Associated with these Ecological Systems
Human Land Use
Recently Disturbed or Modified
Insects, annelida, shrews, vegetable matter, insect larvae. Apparently will also use plant seeds, carrion, and some mushrooms (van Zyll de Jong 1983).
Uses echolocation to orient in darkness (Buchanan 1972). May live in geographic sympatry with Sorex monticolus, S. cinereus, S. palustris, and S. hoyi (Hennings and Hoffmann 1977).
Pregnant from April to July. Average 6.6 young/litter. Females usually don't conceive first year. No first year males showed signs of sexual development. Males begin producing spermatoza early March. Short lifespan, high annual turnover (van Zyll de Jong 1983).
- Literature Cited AboveLegend: View Online Publication
- Carraway, L.N. 1990. A morphologic and morphometric analysis of the 'Sorex vagrans species complex' in the Pacific coast region. Texas Tech Univ. Mus. Spec. Publ. (32): 1-76.
- Carraway, L.N. 1995. A key to recent Soricidae of the western United States and Canada based primarily on dentaries. Occasional Papers of the Natural History Museum, University of Kansas (175):1-49.
- Hennings, D. and R.S. Hoffmann. 1977. A review of the taxonomy of the Sorex vagrans species complex from western North America. Occasional Papers of the Museum of Natural History, the University of Kansas. 68: 1-35.
- Hoffmann, R.S. and D.L. Pattie. 1968. A guide to Montana mammals: identification, habitat, distribution, and abundance. University of Montana, Missoula. 133 pp.
- Van Zyll de Jong, C.G. 1983. Handbook of Canadian mammals. 1. Marsupials and insectivores. National Museum of Natural Sciences, National Museums of Canada, Ottawa, Canada. 210 pp.
- Additional ReferencesLegend: View Online Publication
Do you know of a citation we're missing?
- [WWPC] Washington Water Power Company. 1995. 1994 wildlife report Noxon Rapids and Cabinet Gorge Reservoirs. Washington Water Power Company. Spokane, WA.
- Adelman, E.B. 1979. A survey of the nongame mammals in the Upper Rattlesnake Creek drainage of western Montana. M.S. thesis. University of Montana, Missoula. 129 pp.
- Anaconda Minerals Company, and Camp, Dresser & McKee. 1981. Anaconda Stillwater Project 6-month environmental baseline report. CDM Project No. 3139. Vol. I Appendix. Jan. 15, 1981.
- Buchler, E.R. 1972. The use of echolocation by the wandering shrew, Sorex vagrans Baird. Ph.D dissertation. University of Montana, Missoula. 96 pp.
- Burnett, G.W. 1981. Movements and habitat use of American marten in Glacier National Park, Montana. M.S. thesis. Univ. Mont., Missoula. 130 pp.
- Carlsen, T. 1980. Small mammal trapping in the Elkhorns. [Unpublished report]. 7 pp.
- Carlsen, T. and R. Northrup. 1992. Canyon Ferry Wildlife Management Area Final Draft Management Plan. March 1992.
- Clark, T. W. 1973. Distribution and reproduction of shrews in Grand Teton National Park, Wyoming. Northwest Sci. 47(2): 128-131.
- Clothier, R.R. 1955. Contribution to the life history of Sorex vagrans in Montana. Journal Mammal. 36(2): 214-220.
- Feigley, H.P. 1981. Studies on native small mammals as intermediate hosts of Echinococcus multilocularis. M.Sc. Thesis. Bozeman, Montana: Montana State University. 50 p.
- Foresman, K.R. 2001. The wild mammals of Montana. American Society of Mammalogists, Special Publication Number 12. Lawrence, KS. 278 pp.
- Foresman, K.R. 2012. Mammals of Montana. Second edition. Mountain Press Publishing, Missoula, Montana. 429 pp.
- Gillihan, S. W. and K. R. Foresman. 2004. Sorex vagrans. American Society of Mammalogists, Lawrence, KS. Mammalian Species No. 744:1-5.
- Hanauska-Brown, L., B.A. Maxell, A. Petersen, and S. Story. 2014. Diversity Monitoring in Montana 2008 – 2010 Final Report. Montana Fish, Wildlife & Parks. Helena, MT. 78 pp.
- Hayward, G. D. and P. H. Hayward. 1995. Relative abundance and habitat associations of small mammals in the Chamberlain Basin, central Idaho. Northwest Sci. 69(2): 114-125.
- Heath, M.L. 1973. Small mammal populations in clearcuts of various ages in south central Montana. M.Sc. Thesis. Bozeman, Montana: Montana State University. 33 p.
- Hoffmann, R. S. and R. D. Taber. 1960. Notes on Sorex in the northern Rocky Mountain alpine zone. Journal of Mammalogy 41(2): 230-234.
- Ingles, L. G. 1961. Home range and habitats of the wandering shrew. J. Mammal. 42(4): 455-462.
- Johnson, L.J. 1960. Mammal studies on the Lubrecht Forest, Montana: a preliminary report. Proc. Mont. Acad. Sci. 20: 40-47.
- Joslin, Gayle. 1980. Wildlife inventory and hard rock mining impact analysis of the West Cabinet Mountains and Lake Creek Valley, Lincoln County, Montana. MTFWP 91 pgs + 47 pgs app.
- Koplin, J.R. 1962. Competition and niche segregation in the genus Microtus. M.S. thesis. Montana State University. 66 pp.
- McCracken, K. E. 1990. Microhabitat and dietary partitioning in three species of shrews at Yellow Bay, Montana. M.A. thesis. University of Montana, Missoula. 38 pp.
- Medin, D. E. and W. P. Clary. 1991. Small mammals of a beaver pond ecosystem and adjacent riparian habitat in Idaho. USDA, Forest Service, Res. Paper INT-445.
- Northrop, Devine & Tarbell, Inc. 1994. Cabinet Gorge and Noxon Rapids hydroelectric developments: 1993 wildlife study. Unpublished report to the Washington Water Power Company, Spokane. Vancouver, Washington and Portland, Maine. 144 pp. plus appendices.
- Oechsli, L.M. 2000. Ex-urban development in the Rocky Mountain West: consequences for native vegetation, wildlife diversity, and land-use planning in Big Sky, Montana. M.Sc. Thesis. Montana State University, Bozeman. 73 p.
- Pattie, D.L. and N.A. M. Verbeek. 1967. Alpine mammals of the Beartooth Plateau. Northwest Science 41(3): 110-117.
- Plopper, C.E. 1968. Insular and mainland populations of Peromyscus maniculatus at Flathead Lake, Montana. M.S. thesis. University of Montana, Missoula. 91 pp.
- Ports, M. A. and S. B. George. 1990. Sorex preblei in the northern Great Basin. Great Basin Naturalist 50: 93-95.
- Ramirez, Pedro, Jr. 1977. Small Populations in Different-Aged Clearcuts and Uncut Forests in Northwestern Montana. M. S. thesis. 72 pp.
- Reichel, J.D. 1996. Northern bog lemming survey: 1995. Montana Natural Heritage Program. Helena, MT. 35 pp.
- Reichel, J.D. and S.G. Beckstrom. 1994. Northern bog lemming survey: 1993. Unpublished report. Montana Natural Heritage Program. Helena, MT. 87 pp.
- Reid, F. 2006. Peterson Field Guide to Mammals of North America, 4th Edition. Houghton Mifflin Company: Boston and New York, 608 pp.
- Rust, H. J. 1946. Mammals of northern Idaho. J. Mammal. 27(4): 308-327.
- Smith H.C. 1988. The wandering shrew, Sorex vagrans, in Alberta. Canadian Field-Naturalist. 102:254-156.
- Spencer, A. W. and D. Pettus. 1966. Habitat preferences of five sympatric species of long-tailed shrews. Ecology 47: 677-683.
- Stearns-Roger Inc., 1975, Environmental baseline information of the Mount Vernon Region, Montana. January 31, 1975.
- Thompson, Richard W., Western Resource Dev. Corp., Boulder, CO., 1996, Wildlife baseline report for the Montana [Montanore] Project, Lincoln and Sanders counties, Montana. In Application for a Hard Rock Operating Permit and Proposed Plan of Operation, Montanore Project, Lincoln and Sanders Counties, Montana. Vol. 5. Stroiazzo, John. Noranda Minerals Corp., Libby, MT. Revised September 1996.
- Von Gunten. 1978. Pronghorn fawn mortality on the National Bison Range. M.S. thesis. University of Montana, Missoula. 82 pp.
- Weckwerth, R. P. 1957. The relationship between the marten population and the abundance of small mammals in Glacier National Park. M.S. thesis. University of Montana, Missoula. 76 pp.
- Zackheim, K. 1973. Exhibit H: Wildlife Study. In Ash Grove Cement Co. files.
- Additional Sources of Information Related to "Mammals"