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Urocitellus columbianus

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Columbian Ground Squirrel
(Urocitellus columbianus)
Range
Taxonomic classification
Order:Rodentia
Suborder:Sciuromorpha
Family:Sciuridae
Subfamily:Xerinae
Tribe:Marmotini
Genus:Urocitellus
Binomial details
Urocitellus columbianus (Ord, 1815)
Other resources
Full taxonomic details at MDD

The Columbian Ground Squirrel (Urocitellus columbianus) is one of the largest and most richly colored species in the genus Urocitellus.

Description

From Elliott and Flinders (1991): "a stout-bodied ground squirrel with relatively short, dense pelage. The nose and front of the face are tawny and the dorsum tends to be cinnamon buff, shaded with darker brown of the underfur. The eye ring is pale buff, and sides of neck a pale gray. Flanks tend to be grayish or buffy white; legs, feet, and venter are a cinnamon buff. Tail is black, rather than cinnamon buff above, fuscous-black and grayish-white below (Howell, 1938). Molt pattern is "diffuse" without an external molt line (Hansen, 1954). Upper side of tail in [subspecies] S. c. ruficaudus is more tawny (not gray), sides of face and throat a deeper shade of tawny, and legs and feet darker than [subspecies] S. c. columbianus. Albinism has been observed (Svihla, 1933)."

Columbian Ground Squirrel (Urocitellus columbianus) photographed by Andrey Atuchin in Kananaskis, Alberta, Canada.
Columbian Ground Squirrel (Urocitellus columbianus) photographed by Christopher Lindsey in Wallowa County, Oregon.

Geographic variation and subspecies notes

From Verts and Carraway (1998): "Both of the two nominal subspecies occur in Oregon: the smaller and lighter S. c. columbianus throughout most of the Wallowa and Blue mountains and the larger and darker S. c. ruficaudus only along the southern edge of the range in northern Malheur and Harney counties and southern Grant Co. (Hall, 1981; Howell, 1938). Range maps indicating the absence of S. c. columbianus in Oregon or S. c. ruficaudus as an endemic to Oregon (Elliot and Flinders, 1984, 1991) apparently were lapsus."

  • Urocitellus columbianus photographed by Christopher Lindsey in Wallowa County, Oregon.
  • Urocitellus columbianus photographed by Mark Nikas in Harney County, Oregon.

Museum specimens

  • Holotype: USNM 231942. Urocitellus columbianus ruficaudus. Adult female. Wallowa Lake, Wallowa County, Oregon. Collected 13 April 1919.
  • Holotype: USNM 231942. Urocitellus columbianus ruficaudus. Adult female. Wallowa Lake, Wallowa County, Oregon. Collected 13 April 1919.
  • Holotype: USNM 231942. Urocitellus columbianus ruficaudus. Adult female. Wallowa Lake, Wallowa County, Oregon. Collected 13 April 1919.

External measurements

Length measurements are in millimeters (mm) and weight measurements are in grams (g), unless stated otherwise. If available, the sample size (n=) is provided. If a range is not provided and n= is not given, then the listed measurement represents an average.

Part of range Reference Total length Tail length Hindfoot length Ear length Mass
rangewide Elliot and Flinders (1991) 325–410 80–116 47–57 16–22.5


Skull

  • Holotype: USNM 231942. Urocitellus columbianus ruficaudus. Adult female. Wallowa Lake, Wallowa County, Oregon. Collected 13 April 1919. Dorsal view of the skull.
  • Holotype: USNM 231942. Urocitellus columbianus ruficaudus. Adult female. Wallowa Lake, Wallowa County, Oregon. Collected 13 April 1919. Ventral view of the skull.
  • Holotype: USNM 231942. Urocitellus columbianus ruficaudus. Adult female. Wallowa Lake, Wallowa County, Oregon. Collected 13 April 1919. Lateral view of the skull.
  • Holotype: USNM 231942. Urocitellus columbianus ruficaudus. Adult female. Wallowa Lake, Wallowa County, Oregon. Collected 13 April 1919. Dorsal view of the mandible.
  • Holotype: USNM 231942. Urocitellus columbianus ruficaudus. Adult female. Wallowa Lake, Wallowa County, Oregon. Collected 13 April 1919. Lateral view of the left mandible.

Similar species

Urocitellus columbianus is a wide-ranging species that is sympatric with many Urocitellus ground squirrels. Its range abuts that of the Townsend's Ground Squirrel (Urocitellus townsendii) to the west, but the Columbia River appears to be a major biogeographic barrier for both species. Comparisons with sympatric congeners are provided below. From Elliott and Flinders (1991): "columbianus differs from other species by having buffy dorsal spots and hind feet longer than 43 mm."

Comparison with Urocitellus armatus

Species Subgroup Total length Greatest length of skull Measurement reference
Urocitellus armatus big-eared 280–303 mm 45.6–48.5 mm Eshelman and Sonnemann (2000)
Urocitellus columbianus big-eared 325–410 mm 51.7 mm (ssp. ruficaudus) Elliot and Flinders (1991)
  • Uinta Ground Squirrel (Urocitellus armatus) photographed by pirish761 in Yellowstone National Park, Wyoming. This is a big-eared species recognized by a crown sprinkled with gray and by cinnamon coloring on its head, front of face, and ears. Forelegs are cinnamon buff with pinkish shading towards forefeet.
  • Columbian Ground Squirrel (Urocitellus columbianus) photographed by Andrey Atuchin in Kananaskis, Alberta, Canada. This is a big-eared species. It is one of the largest and most richly colored species in the genus Urocitellus.

Comparison with Urocitellus beldingi

Species Subgroup Total length Greatest length of skull Measurement reference
Urocitellus beldingi big-eared 230–300 mm 41.3–46.3 mm Jenkins and Eshelman (1984)
Urocitellus columbianus big-eared 325–410 mm 51.7 mm (ssp. ruficaudus) Elliot and Flinders (1991)
  • Belding's Ground Squirrel (Urocitellus beldingi) photographed by Roger Woodruff in Tuolumne County, California. This is a big-eared species with a mid-dorsal area often is darker reddish-brown than the sides, although the conspicuousness of this trait varies geographically.
  • Columbian Ground Squirrel (Urocitellus columbianus) photographed by Andrey Atuchin in Kananaskis, Alberta, Canada. This is a big-eared species. It is one of the largest and most richly colored species in the genus Urocitellus.

Comparison with Urocitellus brunneus

From Yensen and Sherman (1997) comparing the Idaho Ground Squirrel (Urocitellus brunneus) with U. columbianus: "distinguished from columbianus by its much smaller size (total length <258 mm vs. >320 mm), lack of rufous color on the throat, and less bushy, shorter tail <65 mm vs. >80 mm)."

Species Subgroup Total length Greatest length of skull Measurement reference
Urocitellus brunneus small-eared* 209–258 mm 36.1–42.5 mm Yensen and Sherman (1997)
Urocitellus columbianus big-eared 325–410 mm 51.7 mm (ssp. ruficaudus) Elliot and Flinders (1991)
  • Idaho Ground Squirrel (Urocitellus brunneus) photographed by Yinan Li in Payette County, Idaho. This is a small, brownish, dorsally-spotted ground squirrel.
  • Columbian Ground Squirrel (Urocitellus columbianus) photographed by Andrey Atuchin in Kananaskis, Alberta, Canada. This is a big-eared species. It is one of the largest and most richly colored species in the genus Urocitellus.

Comparison with Urocitellus canus

Species Subgroup Total length Greatest length of skull Measurement reference
Urocitellus canus small-eared typically <250 mm 34.6–38.7 mm (condylobasal length) Cole and Wilson (2009)
Urocitellus columbianus big-eared 325–410 mm 51.7 mm (ssp. ruficaudus) Elliot and Flinders (1991)
  • Merriam's Ground Squirrel (Urocitellus canus) photographed by Christopher Lindsey in Baker County, Oregon. This is a small-eared species. It is a gray ground squirrel with dorsal pelage that lacks spots or flecks. The sides of the head and the hind legs are tinted with pinkish to reddish buff.
  • Columbian Ground Squirrel (Urocitellus columbianus) photographed by Andrey Atuchin in Kananaskis, Alberta, Canada. This is a big-eared species. It is one of the largest and most richly colored species in the genus Urocitellus.

Comparison with Urocitellus elegans

Species Subgroup Total length Greatest length of skull Measurement reference
Urocitellus columbianus big-eared 325–410 mm 51.7 mm (ssp. ruficaudus) Elliot and Flinders (1991)
Urocitellus elegans big-eared 253–307 mm 43.0–46.8 mm Zegers (1984)
  • Columbian Ground Squirrel (Urocitellus columbianus) photographed by Andrey Atuchin in Kananaskis, Alberta, Canada. This is a big-eared species. It is one of the largest and most richly colored species in the genus Urocitellus.
  • Wyoming Ground Squirrel (Urocitellus elegans) photographed by wyattherp in Grand County, Colorado. This is a big-eared species with upperparts that are light drab and flecked or dappled with light pinkish buff, clay color, pinkish cinnamon, or blackish hairs.

Comparison with Urocitellus idahoensis

Species Subgroup Total length Greatest length of skull Measurement reference
Urocitellus columbianus big-eared 325–410 mm 51.7 mm (ssp. ruficaudus) Elliot and Flinders (1991)
Urocitellus idahoensis small-eared 188 mm (holotype for subspecies artemesiae); 263 mm (holotype for subspecies idahoensis) 32.7–36.2 mm (condylobasal length for subspecies artemesiae); 36.2–39.0 (condylobasal length subspecies idahoensis) McLean (2025)
  • Columbian Ground Squirrel (Urocitellus columbianus) photographed by Andrey Atuchin in Kananaskis, Alberta, Canada. This is a big-eared species. It is one of the largest and most richly colored species in the genus Urocitellus.
  • Snake River Plains Ground Squirrel (Urocitellus idahoensis) photographed by myworldofbirdphotography in Ada County, Idaho. This is a small-eared species. Dorsal color is variegated yellowish-brown with pale yellow dappling that is most distinct on rump but extending to shoulders in some individuals. Top of nose, outer surfaces of the lower hind legs, and underside of the tail are reddish-brown.

Comparison with Urocitellus richardsonii

From Elliott and Flinders (1991): "columbianus differs from other species by having buffy dorsal spots and hind feet longer than 43 mm. The skull resembles that of richardsonii, but is longer, the zygomatic arches are less expanded posteriorly, it is more nearly flat in dorsal outline, the supraorbital margins of frontals are not elevated or thickened, the rostrum and nasals are longer, and the upper toothrows are nearly parallel (Hall, 1981)."

Species Subgroup Total length Greatest length of skull Measurement reference
Urocitellus columbianus big-eared 325–410 mm 51.7 mm (ssp. ruficaudus) Elliot and Flinders (1991)
Urocitellus richardsonii big-eared 277–330 mm 45.1–48.4 mm Michener and Koeppl (1985); Hazard (1982)
  • Columbian Ground Squirrel (Urocitellus columbianus) photographed by Andrey Atuchin in Kananaskis, Alberta, Canada. This is a big-eared species. It is one of the largest and most richly colored species in the genus Urocitellus.
  • Richardson's Ground Squirrel (Urocitellus richardsonii) photographed by Pia Odgaard in Alberta, Canada. This is a big-eared species with upperparts that are pinkish buff or cinnamon buff shaded with fuscous and the posterior part of the back showing a dappled effect. The sides of the head and neck and the fronts of the forelegs are cinnamon buff or clay colored.

Comparison with Urocitellus washingtoni

The Washington Ground Squirrel (Urocitellus washingtoni) is smaller in size (length of hind foot <39 mm) than Belding's Ground Squirrel (Urocitellus beldingi) and Urocitellus columbianus (Rickart and Yensen, 1991).

Species Subgroup Total length Greatest length of skull Measurement reference
Urocitellus columbianus big-eared 325–410 mm 51.7 mm (ssp. ruficaudus) Elliot and Flinders (1991)
Urocitellus washingtoni small-eared 185–245 mm 35.0–41.8 mm Rickart and Yensen (1991)

References

Elliott CL, Flinders JT. 1984. Cranial measurements of the Columbian ground squirrel (Spermophilus columbianus columbianus), with special reference to subspecies taxonomy and juvenile skull development. The Great Basin Naturalist 44:505-508.

Elliott CL, Flinders JT. 1991. Spermophilus columbianus. Mammalian species (372):1-9. https://doi-org.ezproxy1.lib.asu.edu/10.2307/3504178

Hall ER. 1981. The mammals of North America. 2 vols. John Wiley and Sons, New York.

Hansen RM. 1954. Molt patterns in ground squirrels. Proceedings of the Utah Academy of Sciences Arts and Letters 31:57-60.

Howell AH. 1938. Revision of the North American ground squirrels. North American Fauna, 56:1-256.

Rickart EA, Yensen E., 1991. Spermophilus washingtoni. Mammalian Species (371):1-5.

Svihla A. 1933. Occurrence of a colony of albino ground squirrels near Pullman, Washington. The Murrelet 14:78.

Verts BJ, Carraway LN. 1998. Land mammals of Oregon. Berkeley (CA, USA): University of California Press.

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