Northern Grasshopper Mouse - Onychomys leucogaster
FWP Conservation Tier
In Montana the female Northern Grasshopper Mouse averages significantly larger and heavier than the male. It will be approximately 5 3/4 inches in total length and 1 3/10 ounces in weight (Foresman 2012). The Northern Grasshopper Mouse changes upper fur color throughout its life history: grayish as a juvenile, buffy to reddish brown as an adult, and back to grayish in old age (Zeveloff 1988). It is white on the belly, legs and feet, and underside of the short, thick, blunt tail. It is a stocky but efficient miniature predator which makes a long, high-pitched call similar to a Gray Wolf or Coyote howl (Zeveloff 1988 and Kritzman 1977). Long curved claws on large front feet capture and hold insects, other rodents, birds, and reptiles. All of this mouse's feet have furry soles (Foresman 2012).
Summary of Observations Submitted for Montana
Number of Observations:
(Click on the following maps and charts to see full sized version)
Map Help and Descriptions
(Records associated with a range of dates are excluded from time charts)
Found in a wide variety of open habitats, grassland to sagebrush desert. Prefer sandy, silty soils. May construct its own burrows or usurp others. Three types of burrows: nest, retreat and defecation.
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 (high, medium, or low) 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 2001, 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 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 associated as using 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 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.
High, medium, and low habitat quality was assigned based on the degree to which the structural characteristics of an ecological system matched the preferred structural habitat characteristics for each species in the 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 assignments of habitat quality.
If you have any questions or comments on species associations with ecological systems, please contact Bryce Maxell at email@example.com
or (406) 444-3655.
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: http://mtnhp.org/requests/default.asp
) 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. 2001. The wild mammals of Montana. Special Publication No. 12. Lawrence, KS: The American Society of Mammalogists. 278 p.
- 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
Open Water / Wetland and Riparian Systems
Shrubland, Steppe and Savanna Systems
Sparse and Barren Systems
- Occasionally Associated with these Ecological Systems
Shrubland, Steppe and Savanna Systems
Sparse and Barren Systems
A carnivorous rodent, animal matter is up to 80% of diet in spring, 60% of diet in midwinter. Cannibalism not rare. Large intestine shorter than that of most rodents. Primarily eats arthropods.
Highly territorial. Boundaries are scent marked. Occurs at low densities intraspecific interactions aggressive. May deposit feces in shallow pits to mark territory. Males emit high pitched whistle (at night).
Young are weaned within about 3 weeks. Male helps raise the young. The young play like puppies. First litter of year, gestation period 26 to 37 days, later litters 32 to 47 days.
- Additional ReferencesLegend: View WorldCat Record View Online Publication
Do you know of a citation we're missing?
- Allen, K.L., T. Weaver, and D. Flath. 1994. Small mammals in Northern Rocky Mountain ecosystems. Unpubl. report to Bureau of Land Management and United States Forest Service, August 31, 1994. Montana State Univ., Bozeman. 54pp.
- Bailey, V., and C.C. Sperry. 1929. Life history and habits of the grasshopper mice, genus Onychomys. U.S. Dept. Agric. Tech. Bull. 145:1-19.
- Bauer, Delane, 2002, 2002 Four Seasons Wildlife Study. Savage Mine Report, Richland County, Montana.
- Clark, T. W. and M. R. Stromberg. 1987. Mammals in Wyoming. University of Kansas Museum of Natural History, Public Education Series Number 10. xii + 314 p.
- Foresman, K. R. 2001. The wild mammals of Montana. American Society of Mammologists, Special Publication Number 12. Lawrence, KS. 278 p.
- Geppert, T. J. 1984. Small mammals of the Shield Trap, East Pryor Mountain, Montana. M.S. thesis. University of Iowa, Iowa City. 45 pp.
- Hoffmann, R. S. and D. L. Pattie. 1968. A guide to Montana mammals: identification, habitat, distribution, and abundance. University of Montana, Missoula. 133 p.
- Jones, J. K., D. M. Armstrong, R. S. Hoffmann and C. Jones. 1983. Mammals of the northern Great Plains. University of Nebraska Press, Lincoln. 379 p.
- Kritzman, Ellen B. 1977. Little mammals of the Pacific Northwest. Pacific Search Press, Seattle, WA.
- McCarty, R. 1978. ONYCHOMYS LEUCOGASTER. Mamm. Species 87:1-6.
- Powder River Eagle Studies, Inc., Gillette, WY., 2000, Spring Creek Mine 2000 Wildlife Monitoring. March 2000.
- Reid, F. 2006. Peterson Field Guide to Mammals of North America, 4th Edition. Houghton Mifflin Company: Boston and New York, 608 pp.
- Riddle, B.R., and J.R. Choate. 1986. Systematics and biogeography of ONYCHOMYS LEUCOGASTER in western North America. J. Mammal. 67:233-255.
- Western Technology & Engineering, Inc. (WESTECH)., 1991, 1991 Bull Mountains Mine No. 1 Terrestrial Wildlife Monitoring Study. In Meridian Minerals Company Bull Mountains Mine No. 1 Permit Application, Musselshell County, Montana. Vol. 7 of 14: Section 26.4.304(10): Text. Appendix 304(10)-8. January 31, 1990.
- Additional Sources of Information Related to "Mammals"