Family: Sciuridae, Squirrels view all from this family

Description A heavy-bodied marmot. Yellowish brown, with yellowish belly. Feet buff to light brown. Whitish spots between eyes. Buff or yellowish patches below ear to shoulders. Tail bushy. L 18 1/2–28" (470–700 mm); T 5 1/8–8 5/8" (130–220 mm); HF 3–3 1/8" (76–80 mm); Wt 5–10 lb (2.2–4.5 kg).

Similar Species Woodchuck, usually somewhat larger and darker with darker feet, has no white spots between eyes and occurs farther north and east. Hoary Marmot is mainly black and white on head and forepart of body.

Breeding 1 litter per year, of about 5 young, born March–April.

Habitat Rocky areas, talus slopes, valleys, and foothills to elevations of 11,000' (3,300 m).

Range British Columbia, s Alberta, and Montana south through e California and east to Colorado and n New Mexico.

Discussion The Yellow-bellied Marmot feeds entirely on green vegetation of many kinds. In the fall, it puts on a layer of fat, which sustains it through hibernation from August (October in the mountains of New Mexico) through February or March. It lives in a den in a hillside, under a rock pile, or in a crevice or rock shelter. If alarmed, the animal returns to its den and often chirps or whistles from its position of safety. This marmot is a host for the tick that carries Rocky Mountain spotted fever.