Arctic ground squirrel
Spermophilus parryii
TAXONOMY
Arctomys parryii (Richardson, 1825), Hudson Bay, Canada. Seventeen subspecies.
OTHER COMMON NAMES
English: Parka squirrel, Arctic souslik; French: Spermophile arctique; German: Arktisches Erdhörnchen; Spanish: Ardilla terrestre ártica.
PHYSICAL CHARACTERISTICS
Females: 13.7–16.7 in (34.8–42.5 cm), 17.8–35.6 oz (506–1,010g). Males: 14.8–17.1 in (37.7–43.5 cm), 26.1–36.2 oz (740–1,026 g). Head and shoulders cinnamon or tawny colored; back is grayish or buffy brown with white spots. Melanistic forms that are completely black occur in high frequency in the south central Yukon Territory, Canada.
DISTRIBUTION
Eastern Siberia including the Kamtchatka peninsula; northwest North America from Alaska to Hudson Bay, Canada. In Canada, occurs as far south as northwest British Columbia.
HABITAT
Restricted to gravel and sandy areas with good drainage. In arctic habitats burrows are constructed along river banks, lake shores and on moraines and eskers; in alpine habitats, burrows are constructed on stream banks, slopes, and the leading faces of solifluction lobes; in the northern boreal forests, habitat preference is similar to that of the arctic and alpine habitats but also lives along forest edges and clearings.
BEHAVIOR
Lives in small clusters of related females that overlap with the home range of at least one territorial male. Males establish breeding territories immediately after emergence from hibernation in mid April and defend them aggressively against other males. Nearly half of the males die during this period. Males that survive disperse to new territories before hibernation. Juvenile dispersal is male biased and occurs before their first winter hibernation. Adult females enter hibernation beginning in August followed by adult males and juveniles through September.
FEEDING ECOLOGY AND DIET
Eats mainly forbs with a preference for legumes. Will prey upon lemmings (Dicrostonyx torquatus), newborn snowshoe hares (Lepus americanus), and birds' nests. Will consume insects and carrion. Males collect and cache seeds below ground for access during early spring.
REPRODUCTIVE BIOLOGY
Females emerge 2–3 weeks after males. Breeding occurs 3–4 days later during late April to early May. Nearly the entire population breeds, including yearlings. Promiscuous, but first
male sires approximately 90% of pups. Four to ten pups (maximum 12) are born in an underground natal chamber after 25 days gestation. Young appear above ground 27 days after birth.
CONSERVATION STATUS
Three subspecies restricted to a few islands off the coast of Alaska (S. p. kodiacensis, S. p. lyratus, and Citellus undulatus nebulicola) are classified by the IUCN as Data Deficient. Populations of subspecies S. p. plesius in the boreal forest cycle in abundance from 0.2 to 6.9 per acre (0.1 to 2.8 per ha) over an 8-year period. Local extinctions may occur when squirrels are at their cyclic low. Persistent organic pollutants and heavy metals have been detected in squirrels from northern Alaska but levels were low compared with other arctic species.
SIGNIFICANCE TO HUMANS
Northern indigenous people hunt squirrels for food and fur for clothing.
