The Arctic fox (''Vulpes lagopus''), also known as the white fox, polar fox, or snow fox, is a small
fox
Foxes are small to medium-sized, omnivorous mammals belonging to several genera of the family Canidae. They have a flattened skull, upright, triangular ears, a pointed, slightly upturned snout, and a long bushy tail (or ''brush'').
Twelve sp ...
native to the
Arctic
The Arctic ( or ) is a polar region located at the northernmost part of Earth. The Arctic consists of the Arctic Ocean, adjacent seas, and parts of Canada (Yukon, Northwest Territories, Nunavut), Danish Realm (Greenland), Finland, Iceland, N ...
regions of the
Northern Hemisphere and common throughout the
Arctic tundra
In physical geography, tundra () is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. The term ''tundra'' comes through Russian (') from the Kildin Sámi word (') meaning "uplands", "treeless mou ...
biome
A biome () is a biogeographical unit consisting of a biological community that has formed in response to the physical environment in which they are found and a shared regional climate. Biomes may span more than one continent. Biome is a broader ...
.
It is well
adapted
In biology, adaptation has three related meanings. Firstly, it is the dynamic evolutionary process of natural selection that fits organisms to their environment, enhancing their evolutionary fitness. Secondly, it is a state reached by the po ...
to living in cold environments, and is best known for its thick, warm fur that is also used as camouflage. It has a large and very fluffy tail. In the wild, most individuals do not live past their first year but some exceptional ones survive up to 11 years.
Its body length ranges from , with a generally rounded body shape to minimize the escape of
body heat
Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different. A thermoconforming organism, by contrast, simply adopts the surrounding temperature ...
.
The Arctic fox preys on many small creatures such as
lemming
A lemming is a small rodent, usually found in or near the Arctic in tundra biomes. Lemmings form the subfamily Arvicolinae (also known as Microtinae) together with voles and muskrats, which form part of the superfamily Muroidea, which also includ ...
s,
vole
Voles are small rodents that are relatives of lemmings and hamsters, but with a stouter body; a longer, hairy tail; a slightly rounder head; smaller eyes and ears; and differently formed molars (high-crowned with angular cusps instead of lo ...
s,
ringed seal
The ringed seal (''Pusa hispida'') is an earless seal inhabiting the Arctic and sub-Arctic regions. The ringed seal is a relatively small seal, rarely greater than 1.5 m in length, with a distinctive patterning of dark spots surrounded by light ...
pups, fish,
waterfowl
Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species of screamers), Anseranatidae (the magpie goose), and Anatidae, the largest family, which i ...
, and
seabird
Seabirds (also known as marine birds) are birds that are adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same enviro ...
s. It also eats
carrion, berries, seaweed, and insects and other small invertebrates. Arctic foxes form
monogamous pairs during the breeding season and they stay together to raise their young in complex underground dens. Occasionally, other family members may assist in raising their young. Natural predators of the Arctic fox are
golden eagle
The golden eagle (''Aquila chrysaetos'') is a bird of prey living in the Northern Hemisphere. It is the most widely distributed species of eagle. Like all eagles, it belongs to the family Accipitridae. They are one of the best-known birds of ...
s,
Arctic wolves
The Arctic wolf (''Canis lupus arctos''), also known as the white wolf or polar wolf, is a subspecies of grey wolf native to the High Arctic tundra of Canada's Queen Elizabeth Islands, from Melville Island to Ellesmere Island.https://ecor ...
,
polar bears,
wolverine
The wolverine (), (''Gulo gulo''; ''Gulo'' is Latin for " glutton"), also referred to as the glutton, carcajou, or quickhatch (from East Cree, ''kwiihkwahaacheew''), is the largest land-dwelling species of the family Mustelidae. It is a muscul ...
s,
red foxes, and
grizzly bears.
Behavior
![Alopex lagopus IMG 9019](https://upload.wikimedia.org/wikipedia/commons/e/e2/Alopex_lagopus_IMG_9019.JPG)
Arctic foxes must endure a temperature difference of up to between the external environment and their internal core temperature.
To prevent heat loss, the Arctic fox curls up tightly tucking its legs and head under its body and behind its furry tail. This position gives the fox the smallest surface area to volume ratio and protects the least insulated areas. Arctic foxes also stay warm by getting out of the wind and residing in their dens.
Although the Arctic foxes are active year-round and do not hibernate, they attempt to preserve fat by reducing their locomotor activity.
They build up their fat reserves in the autumn, sometimes increasing their body weight by more than 50%. This provides greater insulation during the winter and a source of energy when food is scarce.
Reproduction
In the spring, the Arctic fox's attention switches to reproduction and a home for their potential offspring. They live in large dens in frost-free, slightly raised ground. These are complex systems of tunnels covering as much as and are often in
esker
An esker, eskar, eschar, or os, sometimes called an ''asar'', ''osar'', or ''serpent kame'', is a long, winding ridge of stratified sand and gravel, examples of which occur in glaciated and formerly glaciated regions of Europe and North Ame ...
s, long ridges of sedimentary material deposited in formerly
glaciated
A glacier (; ) is a persistent body of dense ice that is constantly moving under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It acquires distinguishing features, such as ...
regions. These dens may be in existence for many decades and are used by many generations of foxes.
![Fox pups animals](https://upload.wikimedia.org/wikipedia/commons/8/86/Fox_pups_animals.jpg)
Arctic foxes tend to select dens that are easily accessible with many entrances, and that are clear from snow and ice making it easier to burrow in. The Arctic fox builds and chooses dens that face southward towards the sun, which makes the den warmer. Arctic foxes prefer large, maze-like dens for predator evasion and a quick escape especially when red foxes are in the area. Natal dens are typically found in rugged terrain, which may provide more protection for the pups. But, the parents will also relocate litters to nearby dens to avoid predators. When red foxes are not in the region, Arctic foxes will use dens that the red fox previously occupied. Shelter quality is more important to the Arctic fox than the proximity of spring prey to a den.
The main prey in the tundra are lemmings, which is why the white fox is often called the "lemming fox". The white fox's reproduction rates reflect the lemming population density, which cyclically fluctuates every 3–5 years.
When lemmings are abundant, the white fox can give birth to 18 pups, but they often do not reproduce when food is scarce. The "coastal fox" or blue fox lives in an environment where food availability is relatively consistent, and they will have up to 5 pups every year.
Breeding usually takes place in April and May, and the
gestation period is about 52 days. Litters may contain as many as 25 (the largest litter size in the
order Carnivora). The young emerge from the den when 3 to 4 weeks old and are weaned by 9 weeks of age.
Arctic foxes are primarily
monogamous and both parents will care for the offspring. When predators and prey are abundant, Arctic foxes are more likely to be promiscuous (exhibited in both males and females) and display more complex social structures. Larger packs of foxes consisting of breeding or non-breeding males or females can guard a single territory more proficiently to increase pup survival. When resources are scarce, competition increases and the number of foxes in a territory decreases. On the coasts of
Svalbard, the frequency of complex social structures is larger than inland foxes that remain monogamous due to food availability. In Scandinavia, there are more complex social structures compared to other populations due to the presence of the red fox. Also, conservationists are supplying the declining population with supplemental food. One unique case, however, is
Iceland
Iceland ( is, Ísland; ) is a Nordic island country in the North Atlantic Ocean and in the Arctic Ocean. Iceland is the most sparsely populated country in Europe. Iceland's capital and largest city is Reykjavík, which (along with its s ...
where monogamy is the most prevalent. The older offspring (1-year-olds) often remain within their parent's territory even though predators are absent and there are fewer resources, which may indicate
kin selection
Kin selection is the evolutionary strategy that favours the reproductive success of an organism's relatives, even when at a cost to the organism's own survival and reproduction. Kin altruism can look like altruistic behaviour whose evolution i ...
in the fox.
Diet
![Fox with fish](https://upload.wikimedia.org/wikipedia/commons/5/51/Fox_with_fish.jpg)
Arctic foxes generally eat any small animal they can find, including
lemming
A lemming is a small rodent, usually found in or near the Arctic in tundra biomes. Lemmings form the subfamily Arvicolinae (also known as Microtinae) together with voles and muskrats, which form part of the superfamily Muroidea, which also includ ...
s,
vole
Voles are small rodents that are relatives of lemmings and hamsters, but with a stouter body; a longer, hairy tail; a slightly rounder head; smaller eyes and ears; and differently formed molars (high-crowned with angular cusps instead of lo ...
s, other rodents,
hares,
bird
Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweig ...
s,
eggs
Humans and human ancestors have scavenged and eaten animal eggs for millions of years. Humans in Southeast Asia had domesticated chickens and harvested their eggs for food by 1,500 BCE. The most widely consumed eggs are those of fowl, especial ...
, fish, and
carrion. They scavenge on carcasses left by larger predators such as wolves and
polar bears, and in times of scarcity also eat their
feces. In areas where they are present, lemmings are their most common prey,
and a family of foxes can eat dozens of lemmings each day. In some locations in northern Canada, a high seasonal abundance of migrating birds that breed in the area may provide an important food source. On the coast of Iceland and other islands, their diet consists predominantly of birds. During April and May, the Arctic fox also preys on
ringed seal
The ringed seal (''Pusa hispida'') is an earless seal inhabiting the Arctic and sub-Arctic regions. The ringed seal is a relatively small seal, rarely greater than 1.5 m in length, with a distinctive patterning of dark spots surrounded by light ...
pups when the young animals are confined to a snow den and are relatively helpless. They also consume berries and seaweed, so they may be considered
omnivores.
This fox is a significant bird-egg predator, consuming eggs of all except the largest tundra bird species.
Arctic foxes survive harsh winters and food scarcity by either hoarding food or storing body fat subcutaneously and viscerally. At the beginning of winter, one Arctic fox has approximately 14740 kJ of energy storage from fat alone. Using the lowest BMR value measured in Arctic foxes, an average sized fox of would need 471 kJ/day during the winter to survive. In Canada, Arctic foxes acquire from
snow goose
The snow goose (''Anser caerulescens'') is a species of goose native to North America. Both white and dark morphs exist, the latter often known as blue goose. Its name derives from the typically white plumage. The species was previously placed ...
eggs at a rate of 2.7–7.3 eggs/h and store 80–97% of them. Scats provide evidence that they eat the eggs during the winter after caching. Isotope analysis shows that eggs can still be eaten after a year, and the metabolizable energy of a stored goose egg only decreases by 11% after 60 days; a fresh egg has about 816 kJ. Eggs stored in the summer are accessed the following spring prior to reproduction.
Adaptations
The Arctic fox lives in some of the most frigid extremes on the planet, but they do not start to shiver until the temperature drops to . Among its
adaptations for survival in the cold is its dense, multilayered
pelage
Fur is a thick growth of hair that covers the skin of mammals. It consists of a combination of oily guard hair on top and thick underfur beneath. The guard hair keeps moisture from reaching the skin; the underfur acts as an insulating blanket ...
, which provides excellent insulation.
Additionally, the Arctic fox is the only canid whose foot pads are covered in fur. There are two genetically distinct coat color
morphs: white and blue.
The white morph has
seasonal camouflage, white in winter and brown along the back with light grey around the abdomen in summer. The blue morph is often a dark blue, brown, or grey color year-round. Although the blue
allele
An allele (, ; ; modern formation from Greek ἄλλος ''állos'', "other") is a variation of the same sequence of nucleotides at the same place on a long DNA molecule, as described in leading textbooks on genetics and evolution.
::"The chro ...
is dominant over the white allele, 99% of the Arctic fox population is the white morph.
Two similar mutations to
MC1R
The melanocortin 1 receptor (MC1R), also known as melanocyte-stimulating hormone receptor (MSHR), melanin-activating peptide receptor, or melanotropin receptor, is a G protein–coupled receptor that binds to a class of pituitary peptide hormones ...
cause the blue color and the lack of seasonal color change.
The fur of the Arctic fox provides the best insulation of any mammal.
The fox has a low
surface area to volume ratio
The surface-area-to-volume ratio, also called the surface-to-volume ratio and variously denoted sa/vol or SA:V, is the amount of surface area per unit volume of an object or collection of objects.
SA:V is an important concept in science and engi ...
, as evidenced by its generally compact body shape, short muzzle and legs, and short, thick ears. Since less of its surface area is exposed to the Arctic cold, less heat escapes from its body.
[Arctic Fox ''Alopex lagopus''](_blank)
. Department of Environment and Conservation, Government of Newfoundland and Labrador
Sensory modalities
The Arctic fox has a functional
hearing range
Hearing range describes the range of frequencies that can be heard by humans or other animals, though it can also refer to the range of levels. The human range is commonly given as 20 to 20,000 Hz, although there is considerable variati ...
between 125 Hz–16 kHz with a sensitivity that is ≤ 60 dB in air, and an average peak sensitivity of 24 dB at 4 kHz. Overall, the Arctic foxes hearing is less sensitive than the dog and the kit fox. The Arctic fox and the kit fox have a low upper-frequency limit compared to the domestic dog and other carnivores. The Arctic fox can easily hear lemmings burrowing under 4-5 inches of snow. When it has located its prey, it pounces and punches through the snow to catch its prey.
The Arctic fox also has a keen sense of smell. They can smell carcasses that are often left by polar bears anywhere from . It is possible that they use their sense of smell to also track down polar bears. Additionally, Arctic foxes can smell and find frozen lemmings under of snow, and can detect a subnivean seal lair under of snow.
Physiology
![Arctic fox lying in grass - DPLA - 6bbdf7a6ee8c38192bcfad0a6f6dab84](https://upload.wikimedia.org/wikipedia/commons/0/06/Arctic_fox_lying_in_grass_-_DPLA_-_6bbdf7a6ee8c38192bcfad0a6f6dab84.jpg)
The Arctic fox contains advantageous genes to overcome extreme cold and starvation periods.
Transcriptome
The transcriptome is the set of all RNA transcripts, including coding and non-coding, in an individual or a population of cells. The term can also sometimes be used to refer to all RNAs, or just mRNA, depending on the particular experiment. The t ...
sequencing has identified two genes that are under
positive selection
In population genetics, directional selection, is a mode of negative natural selection in which an extreme phenotype is favored over other phenotypes, causing the allele frequency to shift over time in the direction of that phenotype. Under dir ...
:
Glycolipid transfer protein domain containing 1 (GLTPD1) and
V-akt murine thymoma viral oncogene homolog 2 (AKT2). GLTPD1 is involved in the
fatty acid metabolism, while AKT2 pertains to the glucose metabolism and insulin signaling.
The average mass specific
BMR and total BMR are 37% and 27% lower in the winter than the summer. The Arctic fox decreases its BMR via metabolic depression in the winter to conserve fat storage and minimize energy requirements. According to the most recent data, the lower critical temperature of the Arctic fox is at in the winter and in the summer. It was commonly believed that the Arctic fox had a lower critical temperature below . However, some scientists have concluded that this statistic is not accurate since it was never tested using the proper equipment.
About 22% of the total body surface area of the Arctic fox dissipates heat readily compared to red foxes at 33%. The regions that have the greatest heat loss are the nose, ears, legs, and feet, which is useful in the summer for thermal heat regulation. Also, the Arctic fox has a beneficial mechanism in their nose for evaporative cooling like dogs, which keeps the brain cool during the summer and exercise.
The
thermal conductivity
The thermal conductivity of a material is a measure of its ability to conduct heat. It is commonly denoted by k, \lambda, or \kappa.
Heat transfer occurs at a lower rate in materials of low thermal conductivity than in materials of high thermal ...
of Arctic fox fur in the summer and winter is the same; however, the thermal conductance of the Arctic fox in the winter is lower than the summer since fur thickness increases by 140%. In the summer, the thermal conductance of the Arctic foxes body is 114% higher than the winter, but their body core temperature is constant year-round.
One way that Arctic foxes regulate their body temperature is by utilizing a countercurrent heat exchange in the blood of their legs.
Arctic foxes can constantly keep their feet above the tissue freezing point () when standing on cold substrates without losing mobility or feeling pain. They do this by increasing vasodilation and blood flow to a capillary rete in the pad surface, which is in direct contact with the snow rather than the entire foot. They selectively vasoconstrict blood vessels in the center of the foot pad, which conserves energy and minimizes heat loss.
Arctic foxes maintain the temperature in their paws independently from the core temperature. If the core temperature drops, the pad of the foot will remain constantly above the tissue freezing point.
Size
The average head-and-body length of the male is , with a range of , while the female averages with a range of .
In some regions, no difference in size is seen between males and females. The tail is about long in both sexes. The height at the shoulder is . On average males weigh , with a range of , while females average , with a range of .
[''Alopex lagopus'' at th]
Smithsonian
Taxonomy
''Vulpes lagopus'' is a 'true fox' belonging to the genus ''
Vulpes
'' Vulpes '' is a genus of the sub-family Caninae. The members of this genus are colloquially referred to as true foxes, meaning they form a proper clade. The word " fox" occurs in the common names of all species of the genus, but also appea ...
'' of the fox
tribe
The term tribe is used in many different contexts to refer to a category of human social group. The predominant worldwide usage of the term in English is in the discipline of anthropology. This definition is contested, in part due to confli ...
Vulpini
Vulpini is a taxonomic rank which represents the fox-like tribe of the subfamily Caninae (the canines), and is sister to the dog-like tribe Canini.
Genera
Taxonomy
The taxonomy of Carnivora in general and Canidae in particular correlates with ...
, which consists of 12 extant species.
It is classified under the
subfamily Caninae
The Caninae, known as canines, are one of three subfamilies found within the canid family. The other two canid subfamilies are the extinct Borophaginae and Hesperocyoninae. The Caninae includes all living canids and their most recent fossil rel ...
of the canid
family
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...
Canidae. Although it has previously been assigned to its own
monotypic
In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...
''Alopex'', recent
genetic evidence now places it in the genus ''Vulpes'' along with the majority of other foxes.
It was originally described by Carl Linnaeus
Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his Nobility#Ennoblement, ennoblement in 1761 as Carl von Linné#Blunt, Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalise ...
in the 10th edition of ''Systema Naturae'' in 1758 as ''Canis lagopus''. The type specimen
In biology, a type is a particular specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to anchor or centralizes th ...
was recovered from Lapland, Sweden. The generic name ''vulpes'' is Latin
Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
for "fox". The specific name ''lagopus'' is derived from Ancient Greek
Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic p ...
λαγώς (''lagōs'', " hare") and πούς (''pous'', "foot"), referring to the hair on its feet similar to those found in cold-climate species of hares.
Looking at the most recent phylogeny, the Arctic fox and the red fox (''Vulpes vulpes'') diverged approximately 3.17MYA. Additionally, the Arctic fox diverged from its sister group, the kit fox (''Vulpes macrotis''), at about 0.9MYA.
Origins
The origins of the Arctic fox have been described by the "out of Tibet" hypothesis. On the Tibetan Plateau
The Tibetan Plateau (, also known as the Qinghai–Tibet Plateau or the Qing–Zang Plateau () or as the Himalayan Plateau in India, is a vast elevated plateau located at the intersection of Central, South and East Asia covering most of the ...
, fossil
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...
s of the extinct ancestral Arctic fox ('' Vulpes qiuzhudingi'') from the early Pliocene (5.08–3.6 MYA) were found along with many other precursors of modern mammals that evolved during the Pliocene
The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58[isotope
Isotopes are two or more types of atoms that have the same atomic number (number of protons in their nuclei) and position in the periodic table (and hence belong to the same chemical element), and that differ in nucleon numbers (mass numb ...](_blank)
analysis of fossils, researchers claim that the Tibetan Plateau experienced tundra-like conditions during the Pliocene and harbored cold-adapted mammals that later spread to North America and Eurasia during the Pleistocene Epoch
The Pleistocene ( , often referred to as the ''Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in ...
(2.6 million-11,700 years ago).
Subspecies
Besides the nominate subspecies, the common Arctic fox, ''V. l. lagopus'', four other subspecies of this fox have been described:
* Bering Islands Arctic fox, ''V. l. beringensis''
* Greenland Arctic fox, ''V. l. foragoapusis''
* Iceland Arctic fox, ''V. l. fuliginosus''
* Pribilof Islands
The Pribilof Islands (formerly the Northern Fur Seal Islands; ale, Amiq, russian: Острова Прибылова, Ostrova Pribylova) are a group of four volcanic islands off the coast of mainland Alaska, in the Bering Sea, about north ...
Arctic fox, ''V. l. pribilofensis''
Distribution and habitat
The Arctic fox has a circumpolar distribution and occurs in Arctic tundra habitats in northern Europe, northern Asia, and North America. Its range includes Greenland, Iceland, Fennoscandia, Svalbard, Jan Mayen
Jan Mayen () is a Norwegian volcanic island in the Arctic Ocean with no permanent population. It is long (southwest-northeast) and in area, partly covered by glaciers (an area of around the Beerenberg volcano). It has two parts: larger ...
(where it was hunted to extinction) and other islands in the Barents Sea
The Barents Sea ( , also ; no, Barentshavet, ; russian: Баренцево море, Barentsevo More) is a marginal sea of the Arctic Ocean, located off the northern coasts of Norway and Russia and divided between Norwegian and Russian territo ...
, northern Russia, islands in the Bering Sea, Alaska
Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S. ...
, and Canada as far south as Hudson Bay. In the late 19th century, it was introduced into the Aleutian Islands
The Aleutian Islands (; ; ale, Unangam Tanangin,”Land of the Aleuts", possibly from Chukchi ''aliat'', "island"), also called the Aleut Islands or Aleutic Islands and known before 1867 as the Catherine Archipelago, are a chain of 14 large v ...
southwest of Alaska. However, the population on the Aleutian Islands is currently being eradicated in conservation efforts to preserve the local bird population. It mostly inhabits tundra and pack ice
Drift ice, also called brash ice, is sea ice that is not attached to the shoreline or any other fixed object (shoals, grounded icebergs, etc.).Leppäranta, M. 2011. The Drift of Sea Ice. Berlin: Springer-Verlag. Unlike fast ice, which is "fasten ...
, but is also present in Canadian boreal forest
Taiga (; rus, тайга́, p=tɐjˈɡa; relates to Mongolic and Turkic languages), generally referred to in North America as a boreal forest or snow forest, is a biome characterized by coniferous forests consisting mostly of pines, spruc ...
s (northeastern Alberta
Alberta ( ) is one of the thirteen provinces and territories of Canada. It is part of Western Canada and is one of the three prairie provinces. Alberta is bordered by British Columbia to the west, Saskatchewan to the east, the Northwest Ter ...
, northern Saskatchewan
Saskatchewan ( ; ) is a province in western Canada, bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, to the northeast by Nunavut, and on the south by the U.S. states of Montana and North Dak ...
, northern Manitoba
, image_map = Manitoba in Canada 2.svg
, map_alt = Map showing Manitoba's location in the centre of Southern Canada
, Label_map = yes
, coordinates =
, capital = Winn ...
, Northern Ontario
Northern Ontario is a primary geographic and quasi-administrative region of the Canadian province of Ontario, the other primary region being Southern Ontario. Most of the core geographic region is located on part of the Superior Geological Pro ...
, Northern Quebec Northern Quebec (french: le nord du Québec) is a geographic term denoting the northerly, more remote and less populated parts of the Canadian province of Quebec.Alexandre Robaey"Charity group works with Indigenous communities to feed Northern Queb ...
, and Newfoundland and Labrador
Newfoundland and Labrador (; french: Terre-Neuve-et-Labrador; frequently abbreviated as NL) is the easternmost provinces and territories of Canada, province of Canada, in the country's Atlantic Canada, Atlantic region. The province comprises t ...
) and the Kenai Peninsula
The Kenai Peninsula ( Dena'ina: ''Yaghenen'') is a large peninsula jutting from the coast of Southcentral Alaska. The name Kenai (, ) is derived from the word "Kenaitze" or "Kenaitze Indian Tribe", the name of the Native Athabascan Alaskan trib ...
in Alaska. They are found at elevations up to above sea level and have been seen on sea ice close to the North Pole
The North Pole, also known as the Geographic North Pole or Terrestrial North Pole, is the point in the Northern Hemisphere where the Earth's rotation, Earth's axis of rotation meets its surface. It is called the True North Pole to distingu ...
.
The Arctic fox is the only land mammal native to Iceland. It came to the isolated North Atlantic island at the end of the last ice age, walking over the frozen sea. The Arctic Fox Center in Súðavík
Súðavík () is a fishing village and municipality (Súðavíkurhreppur ) on the west coast of Álftafjörður in Westfjords, Iceland.
History
On January 16, 1995, an avalanche fell on the village early in the morning (around 6:25 am) and destr ...
contains an exhibition on the Arctic fox and conducts studies on the influence of tourism on the population. Its range during the last ice age
An ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth's climate alternates between ice ages and gre ...
was much more extensive than it is now, and fossil
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...
remains of the Arctic fox have been found over much of northern Europe and Siberia.
The color of the fox's coat also determines where they are most likely to be found. The white morph mainly lives inland and blends in with the snowy tundra, while the blue morph occupies the coasts because its dark color blends in with the cliffs and rocks.
Image:Iceland-1979445.jpg, Arctic fox in winter pelage, Iceland
Iceland ( is, Ísland; ) is a Nordic island country in the North Atlantic Ocean and in the Arctic Ocean. Iceland is the most sparsely populated country in Europe. Iceland's capital and largest city is Reykjavík, which (along with its s ...
Image:Fjellrev pho.jpg, Arctic fox
Migrations and travel
During the winter, 95.5% of Arctic foxes utilize commuting trips, which remain within the fox's home range. Commuting trips in Arctic foxes last less than 3 days and occur between 0–2.9 times a month. Nomadism is found in 3.4% of the foxes, and loop migrations (where the fox travels to a new range, then returns to its home range) are the least common at 1.1%. Arctic foxes in Canada that undergo nomadism and migrations voyage from the Canadian archipelago to Greenland and northwestern Canada. The duration and distance traveled between males and females is not significantly different.
Arctic foxes closer to goose colonies (located at the coasts) are less likely to migrate. Meanwhile, foxes experiencing low-density lemming populations are more likely to make sea ice trips. Residency is common in the Arctic fox population so that they can maintain their territories. Migratory foxes have a mortality rate >3 times higher than resident foxes. Nomadic behavior becomes more common as the foxes age.
In July 2019, the Norwegian Polar Institute reported the story of a yearling female which was fitted with a GPS
The Global Positioning System (GPS), originally Navstar GPS, is a satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of the global navigation satellite sy ...
tracking device and then released by their researchers on the east coast of Spitsbergen in the Svalbard group of islands. The young fox crossed the polar ice from the islands to Greenland
Greenland ( kl, Kalaallit Nunaat, ; da, Grønland, ) is an island country in North America that is part of the Kingdom of Denmark. It is located between the Arctic and Atlantic oceans, east of the Canadian Arctic Archipelago. Greenland i ...
in 21 days, a distance of . She then moved on to Ellesmere Island in northern Canada
Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...
, covering a total recorded distance of in 76 days, before her GPS tracker stopped working. She averaged just over a day, and managed as much as in a single day.
Conservation status
The Arctic fox has been assessed as least concern
A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. T ...
on the IUCN Red List
The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...
since 2004. However, the Scandinavian mainland population is acutely endangered, despite being legally protected from hunting and persecution for several decades. The estimate of the adult population in all of Norway, Sweden, and Finland is fewer than 200 individuals.[ Of these, especially in Finland, the Arctic fox is even classified as critically endangered, because even though the animal was pacified in Finland since 1940, the population has not recovered despite that. As a result, the populations of Arctic fox have been carefully studied and inventoried in places such as the Vindelfjällens Nature Reserve (Sweden), which has the Arctic fox as its symbol.
The abundance of the Arctic fox tends to fluctuate in a cycle along with the population of lemmings and ]vole
Voles are small rodents that are relatives of lemmings and hamsters, but with a stouter body; a longer, hairy tail; a slightly rounder head; smaller eyes and ears; and differently formed molars (high-crowned with angular cusps instead of lo ...
s (a 3- to 4-year cycle).[ The populations are especially vulnerable during the years when the prey population crashes, and uncontrolled ]trapping
Animal trapping, or simply trapping or gin, is the use of a device to remotely catch an animal. Animals may be trapped for a variety of purposes, including food, the fur trade, hunting, pest control, and wildlife management.
History
Neolithi ...
has almost eradicated two subpopulations.
The pelts of Arctic foxes with a slate-blue coloration were especially valuable. They were transported to various previously fox-free Aleutian Island
The Aleutian Islands (; ; ale, Unangam Tanangin,”Land of the Aleuts", possibly from Chukchi ''aliat'', "island"), also called the Aleut Islands or Aleutic Islands and known before 1867 as the Catherine Archipelago, are a chain of 14 large vo ...
s during the 1920s. The program was successful in terms of increasing the population of blue foxes, but their predation of Aleutian Canada geese conflicted with the goal of preserving that species.
The Arctic fox is losing ground to the larger red fox. This has been attributed to climate change
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to ...
—the camouflage value of its lighter coat decreases with less snow cover. Red foxes dominate where their ranges begin to overlap by killing Arctic foxes and their kits. An alternative explanation of the red fox's gains involves the gray wolf. Historically, it has kept red fox numbers down, but as the wolf has been hunted to near extinction
Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...
in much of its former range, the red fox population has grown larger, and it has taken over the niche of top predator
An apex predator, also known as a top predator, is a predator at the top of a food chain, without natural predators of its own.
Apex predators are usually defined in terms of trophic dynamics, meaning that they occupy the highest trophic le ...
. In areas of northern Europe, programs are in place that allow the hunting of red foxes in the Arctic fox's previous range.
As with many other game species, the best sources of historical and large-scale population data are hunting bag records and questionnaires. Several potential sources of error occur in such data collections. In addition, numbers vary widely between years due to the large population fluctuations. However, the total population of the Arctic fox must be in the order of several hundred thousand animals.
The world population of Arctic foxes is thus not endangered, but two Arctic fox subpopulations are. One is on Medny Island (Commander Islands
The Commander Islands, Komandorski Islands, or Komandorskie Islands (russian: Командо́рские острова́, ''Komandorskiye ostrova'') are a series of treeless, sparsely populated Russian islands in the Bering Sea located about ea ...
, Russia), which was reduced by some 85–90%, to around 90 animals, as a result of mange
Mange is a type of skin disease caused by parasitic mites. Because various species of mites also infect plants, birds and reptiles, the term "mange", or colloquially "the mange", suggesting poor condition of the skin and fur due to the infectio ...
caused by an ear tick introduced by dogs in the 1970s. The population is currently under treatment with antiparasitic drugs, but the result is still uncertain.
The other threatened population is the one in Fennoscandia (Norway, Sweden, Finland, and Kola Peninsula
sjd, Куэлнэгк нёа̄ррк
, image_name= Kola peninsula.png
, image_caption= Kola Peninsula as a part of Murmansk Oblast
, image_size= 300px
, image_alt=
, map_image= Murmansk in Russia.svg
, map_caption = Location of Murmansk Oblas ...
). This population decreased drastically around the start of the 20th century as a result of extreme fur prices, which caused severe hunting also during population lows. The population has remained at a low density for more than 90 years, with additional reductions during the last decade. The total population estimate for 1997 is around 60 adults in Sweden, 11 adults in Finland, and 50 in Norway. From Kola, there are indications of a similar situation, suggesting a population of around 20 adults. The Fennoscandian population thus numbers around 140 breeding adults. Even after local lemming peaks, the Arctic fox population tends to collapse back to levels dangerously close to nonviability.[
The Arctic fox is classed as a "prohibited new organism" under New Zealand's ]Hazardous Substances and New Organisms Act 1996
The Hazardous Substances and New Organisms Act (HSNO) is an Act of Parliament passed in New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North I ...
, preventing it from being imported into the country.
See also
* Arctic rabies virus
Arctic rabies virus is a strain of ''Rabies lyssavirus'' that circulates throughout the arctic regions of Alaska, Canada, Greenland, and Russia. There have been no cases in Sweden or in the mainland of Norway in over 100 years. The virus is, ho ...
References
Further reading
* Nowak, Ronald M. (2005). ''Walker's Carnivores of the World''. Baltimore: Johns Hopkins Press. .
External links
State of the Environment Norway: Arctic fox
Smithsonian Institution – North American Mammals: Vulpes lagopus
*
{{Taxonbar, from=Q82738
Fox, arctic
Holarctic fauna
Mammals described in 1758
Mammals of Europe
Mammals of Asia
Mammals of Greenland
Mammals of Iceland
Mammals of North America
Mammals of Russia
Mammals of Canada
Mammals of the United States
Mammals of the Arctic
Taxa named by Carl Linnaeus
Vulpes