The Wyoming ground squirrel is a medium-sized squirrel averaging between 10 and 12 inches in length. It is brownish gray with a belly that is whitish to buff. The lack of stripes on its body distinguishes it from the golden-mantled ground squirrel. It often sits in an alert upright pose. They are usually found in relatively open country where the soil is well drained so that there burrows remain dry. They often leave piles of debris downslope from their burrows. This also distinguishes them from the golden-mantled ground squirrel which does not leave such piles. They may range between 6,000 and 12,000 feet. In addition to their favored diet of foliage, they may feed on remains of other ground squirrels particularly those along roads and highways.
During mid-summer their food will begin to be converted to fat to sustain them through their period of hibernation. This begins when they have reached a critical amount of fat regardless of external environmental conditions. Usually this occurs in late August or early September.
Soon after hibernation, these ground squirrels breed. The gestation period is a little over four weeks with a brood of five to six on the average. They are weaned by five weeks and then appear above ground by early June.