Hispid Pocket Mouse - Chaetodipus hispidus
State Rank Reason (see State Rank above)
Species is known from less than 10 observations and data to assess the conservation status in Montana are not available, and further surveys are needed.
- Details on Status Ranking and Review
ScoreE - 5,000-20,000 km squared (about 2,000-8,000 square miles)
Comment8,123 square Kilometers from Natural Heritage Program range maps
ScoreU - Unknown. Long-term trend in population, range, area occupied, or number or condition of occurrences unknown
CommentNot enough information exists on the distribution, habitat associations, or population or occupancy indices to assess long term trend
ScoreU - Unknown. Short-term trend in population, range, area occupied, and number and condition of occurrences unknown.
CommentNo data on trends available
ScoreU - Unknown. The available information is not sufficient to assign degree of threat as above. (Severity, scope, and immediacy are all unknown, or mostly [two of three] unknown or not assessed [null].)
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).
CommentNot Intrinsically Vulnerable. Species matures quickly, reproduces frequently, and/or has a high fecundity such that populations recover quickly (< 5 years or 2 generations) from decreases in abundance. Species has good dispersal capabilities such that e
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.
CommentAssociated with steppe habitats that may include some conifer component
Raw Conservation Status Score
3.5 + 0 (geographic distribution) + 0 (environmental specificity) + 0 ( trend) + 0 (intrinsic vulnerability) = 3.5
The pelage of the Hispid Pocket Mouse is harsh, with a rump patch of noticeable spiny bristles. It is ochraceous-buff above and mixed with blackish hairs, the belly is white, and separated from the back by a distinctive lateral stripe of buffy hairs. The tail is sharply bicolored, dark to blackish above and white below, and is equal to or shorter than the length of the head and body. It has fur-lined cheek pouches, as in other pocket mice, but the hind feet are naked. Adults from Nebraska attain the following body measurements: total length 203 to 237 millimeters; tail length 93 to 114 millimeters; hind foot length 23.5 to 29.5 millimeters; and mean weight 32.0 grams (Paulson 1988).
Respective measurements for the lone specimen from Montana are total length 191 millimeters, tail length 94 millimeters, hind foot length 28 millimeters, and weight 33.2 grams (Pefaur and Hoffmann 1971).
The Hispid Pocket Mouse is the largest pocket mouse in Montana and is distinguished by its rough dorsal pelage and the naked soles of its hind feet. On the skull, the mastoids do not project beyond the occipital plane and the auditory bullae are clearly separated. The combination of grooved incisors, hypsodont molars, perforate nasal septum, and fur-lined external cheek pouches distinguish the hispid pocket mouse from other non-heteromyid rodents. For other heteromyid species in Montana, Ord's Kangaroo Rat (Dipodomys ordii) also differs by having greatly elongated hind legs, hind foot length more than 30 millimeters, and the mastoid (rear) region of the skull greatly expanded. The Olive-backed Pocket Mouse (Perognathus fasciatus) also has an unlobed antitragus (fleshy projection) in the ear, occipitonasal length (anterior tip of nasal bone to posterior tip of occipital bone at base of skull) less than 24 millimeters, a uniformly-colored tail, and a hind foot length less than 20 millimeters. The range of the smaller Great Basin Pocket Mouse does not overlap in Montana with the Hispid Pocket Mouse (Foresman 2012a, 2001b).
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)
The Hispid Pocket Mouse is non-migratory; no information on dispersal is available.
The only Montana record for Hispid Pocket Mouse occurred on a north-facing slope that supported grassland dominated by Stipa comata, Carex filifolia, Andropogon scoparium, Agropyron smithii, Aristada longiseta, and Bouteloua gracilis (Pefaur and Hoffmann 1971). Information from other parts of its range suggests that the Hispid Pocket Mouse prefers prairie areas with sparse or moderate vegetation, and has been found in a variety of dry grassland and shrub-grassland habitats. It also occurs in rocky or gravelly areas with heavy soils, not being restricted to sandy soils as are other prairie pocket mice. It has also been found in irrigated cornfields and hayfields. Sleeping and birthing occur in underground burrows (Paulson 1988, Seabloom 2002).
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: 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. 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
Recently Disturbed or Modified
Shrubland, Steppe and Savanna Systems
The Hispid Pocket Mouse eats mostly seeds of grasses, forbs, shrubs, and cacti in winter (81% of the diet in parts of Texas), but also consumes green leaves and some insects (mostly ground beetles) in spring. Large quantities of seeds are stored underground for winter use (Jones et al. 1983, Paulson 1988). The diet in Montana is unknown.
Hispid Pocket Mice are generally solitary and nocturnal. Unlike some other pocket mice, Hispid Pocket Mice are active all year. They leave mounds of dirt at the multiple entrances to their burrows, and entrances are often plugged during the day. Burrows are often dug at the base of shrubs or rock outcrops, and seeds are stored in shallow underground chambers. Predators include rattlesnakes, and most nocturnal carnivorous mammals and birds; Great Horned Owls in Nebraska and Oklahoma prey on this species (Jones et al. 1983, Clark and Stromberg 1987, Paulson 1988). In Montana, other small mammals found in sympatry with Hispid Pocket Mouse included Prairie Vole, Olive-backed Pocket Mouse, Meadow Jumping Mouse, Deer Mouse, and Western Harvest Mouse (Pefaur and Hoffmann 1971).
Populations never seem to be especially dense, thus estimates of density, home range size, and dispersal are not available.
No information specific to Montana is documented. The single individual captured in Montana (in mid-July) was a nulliparous subadult female (Pefaur and Hoffmann 1971).
Throughout its range very little is known about the reproductive biology of this species. It breeds in spring and summer in the north, probably throughout the year in the south, and likely produces 1 to 2 litters of 2 to 9 young; August and September females from South Dakota and Nebraska carried 5 to 6 fetuses (Jones et al. 1983, Paulson 1988).
No special management activities have been developed or implemented for this species in Montana. A thorough small mammal survey of appropriate grassland and shrub-grassland habitats in southeastern Montana is desirable to define the distribution and relative abundance of this species in the state.
- Literature Cited AboveLegend: View Online Publication
- Clark, S.G. and M.R. Stromberg. 1987. Mammals in Wyoming. University of Kansas Museum of Natural History, Public Education Series Number 10. xii + 314 pp.
- Foresman, K.R. 2001. The wild mammals of Montana. American Society of Mammalogists, Special Publication Number 12. Lawrence, KS. 278 pp.
- 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 pp.
- Paulson, D.D. 1988. (Chaetodipus hispidus). Mammalian Species 320:1-4.
- Pefaur, J.E. and R.S. Hoffmann. 1971. Merriam's shrew and hispid pocket mouse in Montana. American Midland Naturalist 86(1):247-248.
- Seabloom, R.W. 2002. Additional records of the Hispid Pocket Mouse in North Dakota. Prairie Naturalist 34:61-62.
- Additional ReferencesLegend: View Online Publication
Do you know of a citation we're missing?
- Flath, D.L. 1979. Nongame species of special interest or concern: Mammals, birds, reptiles, amphibians, fishes. Wildlife Division, Montana Department of Fish and Game. Helena, MT.
- Foresman, K.R. 2012. Mammals of Montana. Second edition. Mountain Press Publishing, Missoula, Montana. 429 pp.
- Reid, F. 2006. Peterson Field Guide to Mammals of North America, 4th Edition. Houghton Mifflin Company: Boston and New York, 608 pp.
- Additional Sources of Information Related to "Mammals"