Arctic Fox

Arctic Fox

Back to mammal species list

Description

The short legs and body, short ears, and dense winter fur of the arctic fox give them a stocky appearance. This fox molts twice each year, shedding their long winter fur in early April.  By late June, short brown summer fur covers the face and legs and upper body. This species has a full coat color change with the turn to winter season.  The change to winter coat occurs in September and October and by November, the white winter coat is complete. Foxes may retain their darker coat throughout the year in areas of less severe climate, with some slight change from brown summer fur to bluish-gray winter fur.

Lifestyle

Arctic foxes live a communal and nomadic life, often forming small bands to scavenge for food.  They do not hibernate during winter months.  They do construct homes called dens which house family groups which often consist of one adult dog (male), a litter, and two vixens (females), with one vixen being a non-breeding animal born the previous year that stays to help care for the next litter.  These dens generally have four to eight entrances and a system of tunnels covering about 30 square meters.

Food Habits

Arctic foxes are omnivorous.  In summer, they feed on small mammals including lemmings and voles.  Foxes denning near rocky cliffs along the sea coast depend heavily on nesting seabirds such as puffins and murres.  When food is plentiful, it is sometimes cached among boulders and in dens for later use.  They eat berries, eggs and scavenge upon remains of marine mammals and caribou.  In winter, foxes venture onto the sea ice to scavenge remains of seals killed by polar bears.

Lifecycle

Arctic fox pups are born in dens excavated by the adults in sandy, well-drained soils of low mounds and riverbanks, which extend from six to twelve feet underground.  Enlarged ground squirrel burrows with several entrances may also be used as dens.  Mating occurs in early March and April, with gestation lasting 52 days.  Litters average seven pups but may contain as many as 15 pups.  Arctic foxes are monogamous and both parents aid in bringing food to the den and in rearing the pups. Pups are fully weaned by 1 ½ months and they first emerge from the den when they are about three weeks old and begin to hunt and range away from the den at about 3 months.  They are born covered with short, velvety, dark brown fur and this fur lengthens and becomes lighter after the pups reach 2 weeks of age.  Family units gradually break up during September and October.  During midwinter, foxes lead a mostly solitary existence except when congregating at the carcasses to feed. They attain sexual maturity at nine to 10 months, however, many die within the first year.

Population Status, Threats & Conservation

In areas where lemmings and voles are the most important summer prey, numbers of foxes often rise and fall with cyclic changes of their prey.  Fewer pups are successfully reared to maturity when food is scarce.  There is evidence indicating that competition for food among young pups accounts for some of the heavy mortality in this age groups.  Arctic foxes are abundant in many areas.  However, they have been driven out of some regions because of predators like the red fox.  Their numbers do not seem to be affected by trapping.  The demand for arctic fox fur has diminished in recent years, however, the use and sale of their pelts is important to the economy of some coastal Native villages.

Sources:
Notebook series ADFG
Dewey, T. and C. Middlebrook. 2007. "Vulpes lagopus" (On-line), Animal Diversity Web