Arctic fox

The Arctic fox comes in two colour variants: white fox and blue fox. The white Arctic fox turns greyish brown with a yellowish white abdomen in summer, while the blue fox is dark all year round. The white variant is the one most commonly found in Norway. Where the Arctic fox lives by the coast, the blue variant is more common. This is probably because their specific camouflage works better in one location than the other.

The Arctic fox is very good at staying warm. Its winter coat is extremely thick and warm, and contains a lot of wool.  The blood vessels in its legs are close together. This means that the warm blood flowing into its paws heats the cold blood flowing back towards its body. The Arctic fox also has short legs, short ears and a short tail – all to ensure that they are not exposed to the cold. An Arctic fox is so good at keeping warm that it is not affected even if the temperature drops to 40 below.

Arctic foxes form pairs that may last their whole lives. Each pair has a territory, which they defend against other Arctic foxes. The size of this territory varies according to where the Arctic foxes live and how much food is available. Arctic fox pairs live in their den all year round. Arctic fox dens are generally dug in gravelly and sandy ridges in the mountains. The den has several rooms and passages, as well as several exits. Because the area around the den is well fertilised with fox droppings and food scraps, such locations can look like a veritable oasis in the barren mountain landscape. An Arctic fox den can remain in use for several years.

The breeding season for Arctic foxes is March to April. The cubs are born 55 days later, i.e. in May or June. Arctic foxes living in the mountains can have a large number of young. This is because there may be a long time between litters. Arctic foxes that have plenty of food will be able to breed every year, in which case the litters will normally be smaller.

When Arctic fox cubs are born, they have thin fur and are blind. They start romping outside the den after three or four weeks. Play is an important way of learning hunting techniques, not to mention social skills. By the time the cubs are eight weeks old, they are the same colour as the adults, and at around ten weeks they start making long trips away from the den. Later in the autumn, the Arctic fox cubs will leave home and look for a mate to settle down with.  Arctic foxes can call out in order to make contact with each other. The Arctic fox’s contact call sounds like this:

In an ecological sense, we speak of there being two types of Arctic fox. That is because some Arctic foxes live high up in the mountains, while others keep to coastal areas, such as those found in Greenland and Svalbard. As the two different habitats have different ecosystems, we speak of there being two different ecotypes of Arctic fox.

One ecotype is called the lemming ecotype, while the other is called the coastal ecotype. The two types eat slightly different things. The type living in the mountains (the lemming ecotype) mostly lives on lemmings and small rodents, while the coastal ecotype has a slightly more diverse diet of ptarmigan, seabirds, eggs and carrion.

The Arctic fox will store food to ensure that it can survive when times are hard. It can also go without food for several weeks, a useful ability when you live in such hostile terrain.

The availability of food affects how many young the Arctic fox can have and how often. In the mountains, this is particularly apparent, as the Arctic fox gives birth to very big litters in years when lemmings are especially plentiful – so-called lemming years.

The Arctic fox is what we call a circumpolar species. That means it is found right around the world (circum) in the polar zone (polar). The Arctic fox is therefore found in most countries in the north.

As previous mentioned, the Arctic fox lives in two types of areaS: in the high mountains and tundra, and by the coast. What both areas havE in common is that they are cold and windswept. 

The Arctic fox used to be common in mountain regions throughout Norway. But now there are so few left that they are found around just a few locations in the country.

In global terms, the Arctic fox is common throughout the northern hemisphere. In Norway, however, it is regarded as critically endangered. It is on the Norwegian Red List. In 2019, it was estimated that we had  280 adult Arctic foxes, three times the number of 2007.

The Arctic fox was, in fact, nearly exterminated by us humans because we wanted its fur. By the time we finally protected the Arctic fox, it was nearly too late. There were just a few animals living here and there.

After we killed nearly all the Arctic foxes for their beautiful fur, they have had trouble re-establishing themselves. There are several reasons for this.

One reason is that they are very scattered and far apart, making it difficult to find a partner. We humans have therefore been breeding Arctic foxes for release into the wild.

Another reason is a shortage of food. The Arctic fox does not find many leftovers from wolverines and other large predators in the mountains, so it is reliant on good years with a lot of lemmings. For reasons we do not fully understand, lemming years are not as frequent as they used to be. As the Arctic fox is reliant on good access to food in order to rear it’s young, this is a problem. In order to help the Arctic fox, humans have installed feeding stations where the arctic fox can find food even if lemmings are in short supply.

Finally, there is climate change, and the increase in red fox numbers in the mountains. This larger competitor steals den sites and can kill arctic foxes. Milder winters are making things easier for the red fox – and therefore more difficult for the Arctic fox. 

In recent years, there have been slightly more Arctic foxes in the mountains, but their future is uncertain.