Spermophilus armatus are found only in a small area of the United States. Their range includes southwestern Montana, western Wyoming, southeastern Idaho and northern central Utah.

(Whitaker 1996)

Biogeographic Regions: nearctic (Native )

endemic to a single nation

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Type of Residency: Year-round

Global Range: (20,000-2,500,000 square km (about 8000-1,000,000 square miles)) Intermountain west region of United States; southern Montana, southeastern Idaho, western Wyoming and north-central Utah.

Spermophilus armatus are fairly large ground squirrels with a body length of 280-303 mm and tail length 63 to 81 mm. Skull length is 46 to 48 mm. The Uinta ground squirrels, as they are commonly named, have mixed, brown-buff colored coats. Their sides are slightly paler and their underbellies are pale buff to white. Their tails are black mixed with buff on top and bottom, with paler buff colored edges. The noses, ears and faces are more cinnamon colored. The ears are small and rounded with short fur.

(Whitaker 1996, Hall 1981)

Range mass: 284 to 425 g.

Length: 30 cm

Weight: 425 grams

• Terrestrial

Spermophilus armatus are found in the sagegrass mountain meadows of the western United States. Here they burrow in the soft soils. They can be found near timberline, in valley pastures, cultivated fields or along irrigation ditches. They are also sometimes found in lawns. They prefer moist habitats with lush vegetation and/or aquatic plants.

(Whitaker 1996, MacClintock 1970)

Terrestrial Biomes: savanna or grassland

Comments: Dry meadows, pastures and cultivated fields in high valleys; also in montane grasslands and shrub-steppes almost to timberline (Eshelman and Sonnemann 2000). Digs underground burrows.

Non-Migrant: Yes. At least some populations of this species do not make significant seasonal migrations. Juvenile dispersal is not considered a migration.

Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).

Locally Migrant: No. No populations of this species make annual migrations of over 200 km.

Spermophilus armatus eat seeds, green vegetation, invertebrates and some vertebrates. They are often found near water, as they prefer succulent plants. They are strong swimmers and swim to retrieve species of aquatic plants. Uinta ground squirrels collect food for their periods of hibernation, during which they rely mostly on seeds stockpiled in their burrows.

(Whitaker 1996, Nowak et al. 1987)

Comments: Feeds primarily on a wide variety of green vegetation and seeds; some invertebrates (e.g. earthworms) (Eshelman and Sonnemann 2000), and some vertebrates; accumulates great reserves of body fat.

Note: For many non-migratory species, occurrences are roughly equivalent to populations.

Estimated Number of Occurrences: 81 to >300

10,000 to >1,000,000 individuals

Comments: Actual abundance unknown, but "frequently occur in meadows and fields from 1219 meters along the Snake River up to 2438 meters in mountainous regions" (Eshelman and Sonnemann 2000).

Lives in large colonies.

Comments: Usually active from spring through late summer (approximately April-August). Dormant during the fall and winter.

The breeding season begins immediately after the end of hibernation in March or April. During this season males attract females with calls and scent markings. Scents are laid down by wiping their faces, which have aprocrine scent glands, against the ground. Breeding is also in part dependent on the social rank of individuals within the colony.

Females give birth to one litter per year usually sometime in May. Gestation length is 28 days. Young first emerge from burrow, 24 days after birth. After this female parental investment is minimal. First-year females bear, on average, 4 to 5 yong per litter, whereas older mothers bear 7 to 8 on average.

(Whitaker 1996, Balph 1984)

Females produce 1 litter of 4-6 altricial young/year. Young are born usually in April (Burt and Grossenheider 1964).

US Federal List: no special status

CITES: no special status

IUCN Red List of Threatened Species: least concern

United States

Rounded National Status Rank: N5 - Secure

Rounded Global Status Rank: G5 - Secure

Reasons: Common within a somewhat restricted range.

Global Protection: Many to very many (13 to >40) occurrences appropriately protected and managed

Like other ground squirrels, Spermophilus armatus are destructive to crops, eating vegetables and harvesting seeds. Their winter stores of food consist almost entirely of seeds, including a significant amount dug up from farmers' plantings.

(Nowak et al. 1987)