Uinta Chipmunk - Tamias umbrinus
The Uinta Chipmunk is a medium-sized chipmunk, with moderately distinct dorsal stripes and generally warm brownish pelage on the flanks, shoulders, and head. In some regions they may be difficult to distinguish from other chipmunk species by sight. The outermost stripe is white bordered by brown, not black. It is more likely to be seen in trees than other chipmunks sharing its range (Bergstrom 1999). Adults may attain the following body measurements: total length 200 to 243 millimeters; tail length 90 to 115 millimeters; hind foot 30 to 35 millimeters; ear 16 to 19 millimeters; weight 55 to 80 grams. Sexes are similar in size (Clark and Stromberg 1987). There are 22 teeth in the skull (dental formula: I 1/1, C 0/0, P 2/1, M 3/3), and the skull is more than 34 millimeters in length.
In Montana, the Uinta Chipmunk is sympatric only with the Least and Yellow-pine Chipmunks, and is larger than both. The outermost light dorsal stripe is white (not grayish or yellowish) and bordered by brown, not black as with other species; similarly all of the central dark dorsal stripes are brownish-black, not black as in the other Montana chipmunks. Unlike the Least Chipmunk, it tends to hold its tail horizontally rather than vertically when running, and is generally darker brownish rather than washed grayish or yellowish. Unlike the Yellow-pine Chipmunk, the belly is whitish. Gray-brown coloration on the face and head separate it from the Red-tailed Chipmunk, which is reddish in those body areas and does not occupy the same part of the state (Foresman 2012).
Western Hemisphere Range
Observations in Montana Natural Heritage Program Database
Number of Observations:
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Map Help and Descriptions
(Observations spanning multiple months or years are excluded from time charts)
No information is available on Uinta Chipmunk movements or home range size for Montana. The species is known elsewhere to be non-migratory; apparently only local movements are made. In Colorado, minimum convex polygon home ranges of radio-tracked individuals were 1.87 to 5.12 hectares, and home range lengths were 179 to 457 meters (Bergstrom 1988).
Habitat use in Montana is unstudied and poorly described. The Uinta Chipmunk is found at high elevation in Carbon and southeastern Park Counties in subalpine forest and at treeline in krummholz vegetation, presumably subalpine fir-Engelmann spruce-whitebark pine (Pattie and Verbeek 1967).
Elsewhere, Uinta Chipmunks are known to frequent coniferous forests at moderate to high elevations (to upper treeline). In Wyoming, they are reported occupying spruce-fir forest, lodgepole pine-Douglas-fir forest, and ponderosa pine forest (Clark and Stromberg 1987). In Colorado, they have been reported in ponderosa pine-Douglas-fir forest (Bergstrom 1988). In more southern regions of the global range, they are most often associated with ponderosa pine habitats, but also are found in drier pinyon pine-juniper woodlands; in California and Nevada they also are found in bristlecone pine woodlands (Bergstrom 1999). They often are found near logs and brush in open areas and at forest edges, sometimes in forest with a closed canopy but an open understory. They excavate burrows beneath rocks and shrubs, but also are arboreal to some degree, spending a fair amount of time in trees and sometimes sleeping and nesting in tree cavities.
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.
Uinta Chipmunks feed primarily on conifer mast (including ponderosa pine and Douglas-fir) and shrub seeds (including juniper, maple, and chokecherry), supplementing these with buds, pollen, and fruits. A relatively large part of the diet is fungi, some of which is acquired through digging. Occasionally they eat insect larvae, birds' eggs, and carrion. In fall, seeds are stored in caches and provide the bulk of the winter food supply (Bergstrom 1999). The diet in Montana has not been reported or studied.
The ecology and life history of the Uinta Chipmunk have not been studied in detail, but apparently are quite similar to that of the Least Chipmunk (Tamias minimus), including activity cycles, foraging behavior, hibernation, predators, and vocalizations (Bergstrom 1999). They are active only during the day. Some individuals in Colorado spend a great deal of time in trees, and are very tree-squirrel-like in food habits and arboreality. Both sexes often sleep and nest in trees. They do not hibernate as deeply as ground squirrels and live through the winter on stored food rather than stored fat. Time of spring emergence from, and fall entry into, hibernation has not been studied in detail; hibernation probably occurs during October to May in Wyoming (Clark and Stromberg 1987).
In Montana, individuals are still active at alpine treeline in early August (Pattie and Verbeek 1967).
Predators have not been reported, but undoubtedly include certain mammals and birds. Uinta Chipmunks are more aggressive in territorial defense than other chipmunk species; they are sympatric with Least Chipmunks and Yellow-pine Chipmunks (Tamias amoenus) in some parts of the range, but segregate by smaller-scale habitat differences. In Montana, the Uinta Chipmunk appears to be the ecological counterpart to the Red-tailed Chipmunk (Tamias ruficaudus) that occupies the majority of the western mountains (Foresman 2012).
Vital statistics and population trends are mostly unknown.
The reproductive biology of Uinta Chipmunk has not been studied in Montana and is largely unstudied elsewhere. It is probably similar to other western chipmunks. Mating likely occurs shortly after spring emergence from hibernation, resulting in the production of a single litter of 4 to 5 altricial young following a gestation period of approximately 30 days. Litters are raised in nests built in burrows, tree cavities, and abandoned bird nests that have had roofs added (Bergstrom 1999). In northwestern Wyoming, lactation has been observed in early and mid-July (Clark and Stromberg 1987). Young are weaned and foraging on their own in mid-July or August. Females probably reach reproductive maturity the summer after birth. Longevity has not been reported.
In Montana, the Uinta Chipmunk is at the extreme northern limit of the global distribution and is considered locally restricted and not abundant (Foresman 2012). No special management activities to conserve this species are in practice, nor are any recognized at this time. Occupancy of high elevation forest in or near designated Wilderness Areas largely buffers this species from timber harvest pressures.
- Literature Cited AboveLegend: View Online Publication
- Bergstrom, B.J. 1988. Home ranges of three species of chipmunks (Tamias umbrinus) as assessed by radiotelemetry and grid trapping. Journal of Mammalogy 69:190-193.
- Bergstrom, B.J. 1999. Uinta chipmunk (Tamias umbrinus). Pp. 391-393, in D. E. Wilson and S. Ruff, editors. The Smithsonian book of North American mammals. Smithsonian Institution Press, Washington, D. C. 750 pp.
- 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. 2012. Mammals of Montana. Second edition. Mountain Press Publishing, Missoula, Montana. 429 pp.
- Pattie, D.L. and N.A. M. Verbeek. 1967. Alpine mammals of the Beartooth Plateau. Northwest Science 41(3): 110-117.
- Additional ReferencesLegend: View Online Publication
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- Bergstrom, B. J. and R. S. Hoffmann. 1991. Distribution and diagnosis of three species of chipmunks (Tamias) in the Front Range of Colorado. Southwestern Naturalist 36:14-28.
- Dice, L.R. 1923. Mammal associations and habitats of the Flathead Lake Region, Montana. Ecology 4(3): 247-260.
- Flath, D. L. 1984. Vertebrate species of special interest or concern. Mammals, birds, reptiles, amphibians, fishes. Spec. Publ. Montana Department of Fish, Wildlife, and Parks, Helena. 76 pp.
- 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. 2001. The wild mammals of Montana. American Society of Mammalogists, Special Publication Number 12. Lawrence, KS. 278 pp.
- Hoffmann, R.S. and D.L. Pattie. 1968. A guide to Montana mammals: identification, habitat, distribution, and abundance. University of Montana, Missoula. 133 pp.
- Hoffmann, R.S., P.L. Wright, and F.E. Newby. 1969. The distribution of some mammals in Montana. I. Mammals other than bats. Journal of Mammalogy 50(3): 579-604.
- Jones, J. K., Jr., R. S. Hoffman, D. W. Rice, C. Jones, R. J. Baker, and M. D. Engstrom. 1992. Revised checklist of North American mammals north of Mexico, 1991. Occasional Papers, The Museum, Texas Tech University, 146:1-23.
- Levenson, H., et al. 1985. Systematics of the Holarctic chipmunks (Tamias). Journal of Mammalogy 66:219-242.
- Patterson, B. D. 1984. Mammalian extinction and biogeography in the southern Rocky Mountains. Pages 247-293 in M. H. Nitecke, editor. Extinctions. University of Chicago Press, Chicago, Illinois.
- Reid, F. 2006. Peterson Field Guide to Mammals of North America, 4th Edition. Houghton Mifflin Company: Boston and New York, 608 pp.
- Sutton, D. A. 1992. Tamias amoenus. Am. Soc. Mamm., Mammalian Species No. 390:1-8.
- White, J. A. 1953. Geographic distribution and taxonomy of the chipmunks of Wyoming. University of Kansas Publications, Museum of Natural History 5:583-610.
- White, J.A. 1953. Taxonomy of the chipmunks, Eutamias quadrivitatus and Eutamias umbrinus. University of Kansas Publications, Museum of Natural History 5(33):565-582.
- Additional Sources of Information Related to "Mammals"