Squirrels of the World

Urocitellus parryii 361

geographic variation: Ten subspecies are recognized.

U. p. parryii—northern coast of the Yukon and the North-
west Territories (Canada) and extreme northeast Alaska
(USA). The upperparts are yellowish brown and dusky,
with gray spots. The top of the head and the sides of the
neck are a rich reddish brown to yellowish brown. The
terminal part of the tail is black.
U. p. ablusus—western and southwestern coast of Alaska
(USA). This subspecies has a brown and weakly spotted
dorsum.
U. p. kennicottii—northwestern coast of Alaska (USA). This
subspecies is a pale form.
U. p. kodiacensis—endemic to Kodiak Island, in southwest-
ern Alaska (USA). This subspecies is heavily spotted with
smallish fl ecks that are sometimes faint.
U. p. leucostictus—northeastern Siberia (Russia). The top of
the head is a deep rufous. The dorsum is yellowish brown
and heavily spotted with white.
U. p. lyratus—endemic to St. Lawrence Island, Alaska (USA).
This is a pale and grayish brown subspecies.
U. p. nebulicola—endemic to the Shumagin Islands of south-
western Alaska (USA). This is a diminutive brown and
weakly spotted form.
U. p. osgoodi—south of the Brooks Range in central Alaska
(USA). This is the largest subspecies, with a very red belly.
U. p. plesius—southeastern Alaska (USA), Yukon, Northwest
Territories, Nunavut, and northern British Columbia
(Canada). This is a diminutive and pale gray subspecies.
U. p. stejnegeri—Kamchatka (Russia). The dorsum lacks a ful-
vous suff usion, and the tail is more extensively black.

conservation: IUCN status—least concern. Population
trend—no information.

habitat: Artic ground squirrels live in open arctic tundra,
forest meadows, and meadow-steppe habitats, particularly
meadows with talus in alpine and subalpine zones in the
mountains. They can be found near human settlements.

natural history: This species is diurnal. Arctic ground
squirrels hibernate for up to seven months in burrows.
Adult females enter hibernation in September, followed by
males a few weeks later in October. Juveniles immerge by
the end of October. In March or April, males emerge to es-
tablish large territories; females emerge in another two to
three weeks and establish their home ranges within a male’s
territory. A male defends access to several females within
his territory. Mating occurs during a two-week period soon
after the females emerge, involving all individuals that are
more than 1 year old; more than 75 percent of females pro-

duce a litter each year. Although females mate with one to

four males, the fi rst male sires the off spring in more than 90

percent of the cases; the territory’s resident male is most

often the fi rst male to mate. After a gestation of 25 days, a

litter of six to eight (maximum of 14) young is born within

the burrow. Juveniles emerge after 6 weeks, typically in late

June or early July, and weaning occurs at about 8 weeks of

age. Colonies are composed of a complex system of bur-

rows. Burrows tend to be shallow (less than 1 m deep); per-

manent burrows have several entrances and nest chambers,

compared with short and shallow escape burrows. Primar-

ily herbivorous, U. parryii feeds on leaves, shoots, fl owers,

seeds, and the berries of many tundra grasses, sedges, and

forb s, a s wel l a s on f u n g i , mo s s e s, a nd l ic hen s. A rc t ic g rou nd

squirrels are opportunistic and will eat insects and small

vertebrates; infanticide is known. Males, in particular, col-

lect seeds in their cheek pouches late in the active season to

build substantial underground caches that will provide a

food source to last until the following spring. Principal

predators include ermines (Mustela erminea), foxes, wolver-

ines (Gulo gulo), wolves (Canis lupus), grizzly bears (Ursus arc-

tos horribilis), raptors, gulls, and jaegers. Annual survival

rates for adults and juvenile females average from 25 to 40

percent, with the vast majority of deaths occurring over the

winter. U. parryii has distinct alarm vocalizations for ter-

restrial predators (a “cheek-chick” call) and for aerial preda-

tors (a shrill whistle). Arctic ground squirrels are hunted

primarily for their pelts; they can be a nuisance around hu-

man structures.

general references: Boonstra et al. 2001; Eddingsaas et

al. 2004; Gillis, Hik, et al. 2005; Gillis, Morrison, et al. 2005;

Karels et al. 2000; Lacey and Wieczorek 2001; McLean 1982.

Urocitellus parryii. Photo courtesy Nichole Cudworth.