The Arctic fox, also referred to as the snow fox, is an animal adapted to survive in the Arctic regions of the Northern Hemisphere. With a circumpolar distribution, it thrives in vast, treeless tundra environments, often near rocky coastlines. Its ability to endure temperatures as low as -70 °C is attributed to its thick, insulating fur and compact body shape. This resilience in one of Earth’s most challenging habitats is intrinsically linked to its resourceful and adaptable dietary habits.
Primary Food Sources
The primary diet of the Arctic fox consists of small mammals, making it a predator with acute senses. Lemmings and voles are staple prey, and their availability significantly influences fox populations. Arctic foxes possess an acute ability to detect these rodents moving beneath layers of snow. Once a lemming’s location is pinpointed, the fox employs a unique hunting technique called “mousing,” where it leaps several feet into the air and plunges headfirst into the snow to capture its prey.
Beyond rodents, Arctic foxes also prey on various birds, including ptarmigans and nesting seabirds like auklets, puffins, and murres, particularly in coastal areas during the summer. They also consume bird eggs. An average family of Arctic foxes can consume around 60 rodents per day during the summer months. The populations of Arctic foxes fluctuate in response to cyclic changes in lemming numbers, which typically occur every three to five years. When lemming populations are high, fox litters can be much larger, with females sometimes giving birth to up to 18 pups.
Dietary Flexibility and Seasonal Adaptations
The Arctic fox demonstrates dietary flexibility, adapting its feeding strategies to varying food availability. As opportunistic feeders, they supplement their primary diet with various other food sources. During periods of scarcity, they frequently scavenge on carrion, including the remains of seals left by polar bears on sea ice, caribou, or other marine mammals washed ashore. This scavenging behavior is especially important in winter when live prey is less abundant.
In addition to meat, their omnivorous diet includes plant matter such as berries and seaweed. They also consume fish, shellfish, insects, and marine invertebrates. To survive periods of lean food availability, Arctic foxes engage in food caching, burying surplus food items like eggs or small mammals among boulders or within their dens. These cached provisions can be accessed during the winter months, with studies showing that eggs can remain edible for up to a year when stored in the permafrost. This ability to adapt their diet and store food is important for their survival in their environment.