Wherever it roams in the world Vulpes lagopus goes by many names. These include White Fox, Polar Fox or Snow Fox, but this small mammal is commonly known as the Arctic Fox. Vulpes is derived from the Latin word Fox and lagopus means “hair on its feet” in Greek. The species used to be known as Aloplex lagopus where Aloplex is Fox in Greek, but they have been placed into the genus Vulpes instead as they have a better genetic fit with the majority of other foxes.
Arctic Foxes inhabit much of the terrestrial Arctic Circle, and are mostly prevalent in Arctic tundra where the subsoil is often frozen and the very low temperatures restrict tree growth. The common vegetation found in tundra is shrubs, grasses, mosses and lichen. The tundra is frozen for most of the year with the soil being frozen between 250 to 900mm (9.8 to 35.4 in) deep and hence why trees don’t grow. Winter can see average temperatures of −28 °C (−18 °F) and at extremes can go to −50 °C (−58 °F). The summer temperatures average 12 °C (54 °F), which generally melt the upper layers of frozen soil and turning much of the landscape into marshes. Winds can reach up to 48–97 kmph (30–60 mph) making the tundra very windy. The conditions of the tundra are very harsh, but the Arctic Fox has made it home.
Among the Fox’s physical adaptations to the tundra climate is thick fur, thermo-regulating feet, low surface area to volume ratio with rounder compact bodies, shorter legs and muzzle (less surface area to lose heat) and high body fat. The fox also has larger feet for its size, which helps spread foot-loads and improves movement on snow. These features help the fox to be suited for winter. During winter the foxes also have reduced metabolic rates to help with the cold or food shortages. They are also known to be good swimmers and can swim for over 45 minutes for up to 2 km. In Summer the fur becomes blue-brown and shorter than the winter fur.
The biodiversity of tundra is low and supports around 1700 species of plants and 48 species of land mammals but bird migrations to the marshes are known to occur. Common animals found in the tundra along with the Arctic Fox are Reindeer, Musk Ox, Arctic Hare, Snowy Owl, Polar Bear and Lemmings. Habitat conservation programs have been initiated by Russia and Canada to preserve the wildlife within the tundra through the Biodiversity Action Plan.
Foxes remain active all year around and prefer nocturnal activity, but they are adaptable enough to match activity patterns of their prey. Arctic Foxes home range includes large areas of tundra and coastal habitats. A fox den can be a large complex tunnel network and can potentially house several generations of foxes. A den may cover over 50 m^2 with over 100 different entrances and tunnels usually are 340mm in diameter. In Summer, the den is used for rearing young and providing shelter, and dens are excavated from crests of slopes, banks or mounds.
Families are made up of a mating pair and their progeny. Ocassionally, the family can be supplemented with other adults which may help rear young. Litter sizes ranges between 6 to 12 young and can go upto 25 depending on food availability. Males will hunt and rest alone, but together with the female will feed the pups with prey. The parents would approach the den and call out to their pups with a low chittering sound. Feeding is first come, first serve and is usually regurgitated prey. The parents rarely play with their young, and will visit the den less regularly during the summer only to return to feed the pups or rest. The young will then start to eat stored food and hunt on their own. The young leave their dens during Autumn and until the next breeding season will live a highly mobile and solitary life.
Their diet consists of smaller animals like lemmings, voles, hares, birds, eggs and fish. They have excellent hearing and can locate prey under the snow. When it does find prey, the fox pounces and pushes through the snow to get to the prey. They often store their food during times of abundance in either scattered caches or larder caches. Arctic Foxes have been known to follow Polar Bears or Wolves to scavenge for recent kills. Around human settlements foxes may rummage through garbage. Berries frozen in Autumn can be eaten during Winter as reserve food in shortages. Red Foxes are natural competitors for the same prey, and may kill Arctic Foxes.
Natural predators of the foxes are eagles, snowy owls, large hawks, jaegers, polar bears, wolves, wolverines and red foxes. Humans also historically killed the fox as pest control and for their fur. Starvation is a common cause of death for the foxes during migration and in winter. The species is at little risk of being endangered and is rated “least concern” on the conservation status.
The Arctic Fox is classed as a “prohibited new organism” under New Zealand’s Hazardous Substances and New Organism’s Act 1996 preventing it from being imported into the country as a means to protect native flightless bird populations.
The Arctic Fox became one of my favourite animals and eventually the basis of many things I’ve made, and I owe it to a National Geographic screensaver and that grinning Arctic Fox face.
There’s a lot of good material on the net, so have a look and enjoy.
Wikipedia – a nice source of info
Tundra Animals – Arctic Fox – good facts
ARKive – interesting facts
BBC Nature – Arctic Fox – pretty good videos
Flickriver – a fantastic photo collection
Below are some photos from the internet. These were taken by some very talented photographers and all credit to them and their work. Gotta thank the foxes too !