Jump to content
Main menu Navigation ●Main page ●Contents ●Current events ●Random article ●About Wikipedia ●Contact us ●Donate Contribute ●Help ●Learn to edit ●Community portal ●Recent changes ●Upload file
●Create account ●Log in ●Create account ● Log in Pages for logged out editors learn more ●Contributions ●Talk
View source for Arctic fox

●Article ●Talk ●Read ●View source ●View history Tools Actions ●Read ●View source ●View history General ●What links here ●Related changes ●Upload file ●Special pages ●Page information ●Get shortened URL ●Download QR code ●Wikidata item Appearance ← Arctic fox You do not have permission to edit this page, for the following reason:
This page is currently semi-protected so that only established, registered users can edit it.
Why is the page protected?

While most articles can be edited by anyone, semi-protection is sometimes necessary to prevent vandalism to popular pages.
The reason for protection can be found in the protection log. If there are no relevant entries in the protection log, the page may have been moved after being protected.
What can I do?

If you have a user account, log in first. If you do not yet have an account, you may create one; after 4 days and 10 edits, you will be able to edit semi-protected pages.
Discuss this page with others.
For move-protected pages, see requested moves.
Request that the page's protection level be reduced.
Find out more about how to get started editing Wikipedia.
If you have noticed an error or have a suggestion for a simple, non-controversial change, you can submit an edit request by clicking the button below and following the instructions. An established user may then make the change on your behalf. Please check the talk page first in case the issue is already being discussed.
Submit an edit request
If you wrote any text, please save it temporarily to your device until you can edit this page.
You can view and copy the source of this page:
{{Short description|Species of fox}}
{{Other uses}}
{{Redirect|White fox||White Fox (disambiguation)}}
{{pp|small=yes}}
{{pp-move-indef|small=yes}}
{{Use dmy dates|date=January 2024}}
{{Speciesbox
| name = Arctic fox
| image = Iceland-1979445 (cropped 3).jpg
| status = LC
| status_system = IUCN3.1
| status_ref =<ref name=iucn>{{cite iucn |title=''Vulpes lagopus'' |name-list-style=amp |author=Angerbjörn, A. |author2=Tannerfeldt, M. |date=2014 |page=e.T899A57549321 |doi=10.2305/IUCN.UK.2014-2.RLTS.T899A57549321.en |access-date=19 November 2021}}</ref>
| status2 = G5
| status2_system = TNC
| status2_ref = <ref name="NatureServe">{{cite web|title=Vulpes lagopus|url=https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.100927/Vulpes_lagopus|website=[[NatureServe]] Explorer|access-date=17 April 2024}}</ref>
| taxon = Vulpes lagopus
| authority = ([[Carl Linnaeus|Linnaeus]], [[10th edition of Systema Naturae|1758]])<ref>{{cite book |last=Linnæus|first=C. |title=Systema naturæ per regna tria naturæ, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I|year=1758 |publisher=Laurentius Salvius |location=Holmiæ (Stockholm) |page=40 |chapter=''Vulpes lagopus'' |chapter-url=https://www.biodiversitylibrary.org/item/80764#page/50/mode/1up |edition=10th |access-date=23 November 2012 |language=la |url-status=live |archive-url=https://web.archive.org/web/20121108003214/http://www.biodiversitylibrary.org/item/80764#page/50/mode/1up|archive-date=8 November 2012 |df=dmy-all}}</ref>
| range_map = Cypron-Range Vulpes lagopus.svg
| range_map_caption = Arctic fox range
| synonyms ={{Unbulleted list|
* ''Alopex lagopus'' <small>(Linnaeus,&nbsp;1758)</small>
* ''Canis lagopus'' <small>Linnaeus,&nbsp;1758</small>
* ''Canis fuliginosus'' <small>Bechstein,&nbsp;1799</small>
* ''Canis groenlandicus'' <small>Bechstein,&nbsp;1799</small>
* ''Vulpes arctica'' <small>Oken,&nbsp;1816</small>
* ''Vulpes hallensis'' <small>Merriam,&nbsp;1900</small>
* ''Vulpes pribilofensis'' <small>Merriam,&nbsp;1903</small>
* ''Vulpes beringensis'' <small>Merriam,&nbsp;1903</small>
}}
| synonyms_ref = <ref>{{cite book|last1=Oken|first1=L. |title=Lehrbuch der Naturgeschichte |date=1816 |publisher=August Schmid und Comp.|location=Jena, Germany |volume=3 |page=1033|url=https://archive.org/stream/bub_gb_S5o5AAAAcAAJ#page/n1057/mode/1up}}</ref><ref>{{cite journal|last1=Merriam|first1=C.H. |title=Papers from the Harriman Alaska Expedition. I. Descriptions of twenty-six new mammals from Alaska and British North America|journal=Proceedings of the Washington Academy of Sciences |date=1900|volume=2|pages=15–16 |url=https://www.biodiversitylibrary.org/page/8872019|jstor=24525852|url-status=live|archive-url=https://web.archive.org/web/20180304210706/https://www.biodiversitylibrary.org/page/8872019|archive-date=4 March 2018|df=dmy-all}}</ref><ref name=Merriam1902>{{cite journal|last1=Merriam|first1=C.H. |title=Four New Arctic Foxes |journal=Proceedings of the Biological Society of Washington |date=1902 |volume=15|page=171|url=https://www.biodiversitylibrary.org/page/3830761|url-status=live|archive-url=https://web.archive.org/web/20180304210706/https://www.biodiversitylibrary.org/page/3830761|archive-date=4 March 2018|df=dmy-all}}</ref>{{sfn|Merriam|1902|pp=171–172}}
}}
The '''Arctic fox''' ('''''Vulpes lagopus'''''), also known as the '''white fox''', '''polar fox''', or '''snow fox''', is a small species of [[fox]] native to the [[Arctic]] regions of the [[Northern Hemisphere]] and common throughout the [[Tundra#Arctic tundra|Arctic tundra]] [[biome]].<ref name=iucn /><ref name=msw3>{{MSW3 Wozencraft |id=14000873}}</ref><ref>{{Cite web|url=https://www.nationalgeographic.com/animals/mammals/a/arctic-fox/|archive-url=https://web.archive.org/web/20161105080433/http://www.nationalgeographic.com/animals/mammals/a/arctic-fox/|url-status=dead|archive-date=5 November 2016|title=Arctic Fox {{!}} National Geographic|date=2010-09-10|website=Animals|access-date=2019-01-28}}</ref><ref>{{Cite web |title=Arctic fox {{!}} mammal {{!}} Britannica |url=https://www.britannica.com/animal/Arctic-fox |access-date=2023-04-08 |website=www.britannica.com |language=en}}</ref> It is well [[adaptation|adapted]] 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.<ref name="dx.doi.org" /> Its body length ranges from {{cvt|46|to|68|cm}}, with a generally rounded body shape to minimize the escape of [[body heat]].

The Arctic fox preys on many small creatures such as [[lemming]]s, [[vole]]s, [[ringed seal]] pups, fish, [[waterfowl]], and [[seabird]]s. It also eats [[carrion]], berries, seaweed, and insects and other small [[invertebrate]]s. Arctic foxes form [[Monogamy in animals|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]]s,<ref>[https://www.flr.gov.nl.ca/wildlife/snp/programs/education/animal_facts/mammals/arctic_fox.html Arctic Fox] at Fisheries and Land Resources</ref> [[arctic wolf|Arctic wolves]], [[polar bear]]s,<ref>[https://web.archive.org/web/20161105080433/http://www.nationalgeographic.com/animals/mammals/a/arctic-fox/ Arctic Fox] at National Geographic</ref> [[wolverine]]s, [[red fox]]es, and [[grizzly bear]]s.<ref name="ReferenceB">{{cite journal|last1=Gallant|first1=D. |author2=Reid, D.G. |author3=Slough, B.G. |author4=Berteaux, D. |title=Natal den selection by sympatric arctic and red foxes on Herschel Island, Yukon, Canada|journal=Polar Biology |date=2014 |volume=37 |issue=3 |pages=333–345|doi=10.1007/s00300-013-1434-1|bibcode=2014PoBio..37..333G |s2cid=18744412}}</ref><ref name="doi.org">{{cite journal |last1=Noren|first1=K. |author2=Hersteinsson, P. |author3=Samelius, G. |author4=Eide, N.E. |author5=Fuglei, E. |author6=Elmhagen, B. |author7=Dalén, L. |author8=Meijer, T. |author9=Angerbjörn, A. |name-list-style=amp |title=From monogamy to complexity: social organization of arctic foxes (''Vulpes lagopus'') in contrasting ecosystems |journal=Canadian Journal of Zoology|date=2012|volume=90|issue=9|pages=1102–1116 |doi=10.1139/z2012-077}}</ref>

==Behavior==
[[File:Alopex lagopus IMG 9019.JPG|thumb|left|A sleeping Arctic fox with its fluffy tail wrapped around itself and over its face]]
Arctic foxes must endure a temperature difference of up to {{cvt|90-100|C-change}} between the external environment and their internal core temperature.<ref name="ReferenceC">{{cite journal|last1=Fuglesteg|first1=B. |author2=Haga, Ø.E. |name-list-style=amp |author3=Folkow, L.P. |author4=Fuglei, E. |author5=Blix, A.S. |title=Seasonal variations in basal metabolic rate, lower critical temperature and responses to temporary starvation in the arctic fox (''Alopex lagopus'') from Svalbard|journal=Polar Biology |date=2006 |volume=29 |issue=4 |pages=308–319|doi=10.1007/s00300-005-0054-9|bibcode=2006PoBio..29..308F |s2cid=31158070}}</ref> 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.<ref name="ReferenceD">{{cite journal|last1=Prestrud|first1=P. |s2cid=45830118|title=Adaptations by the Arctic Fox (''Alopex lagopus'') to the Polar Winter|journal=Arctic |date=1991|volume=44|issue=2|pages=132–138 |jstor=40511073|doi=10.14430/arctic1529}}</ref><ref name="ReferenceC" /> Although the Arctic foxes are active year-round and do not hibernate, they attempt to preserve fat by reducing their locomotor activity.<ref name="ReferenceD" /><ref name="ReferenceE">{{cite journal |last1=Klir|first1=J. |last2=Heath|first2=J. |name-list-style=amp |title=An Infrared Thermographic Study of Surface Temperature in Relation to External Thermal Stress in Three Species of Foxes: The Red Fox (''Vulpes vulpes''), Arctic Fox (''Alopex lagopus''), and Kit Fox (''Vulpes macrotis'') |journal=Physiological Zoology|date=1991|volume=65|issue=5|pages=1011–1021 |jstor=30158555|doi=10.1086/physzool.65.5.30158555|s2cid=87183522}}</ref> 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.<ref name="NOAA" />

===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 {{cvt|1000|m2}} and are often in [[esker]]s, long ridges of sedimentary material deposited in formerly [[Glacier|glaciated]] regions. These dens may be in existence for many decades and are used by many generations of foxes.<ref name="NOAA" />

[[File:Fox pups animals.jpg|thumb|Pups of Arctic fox with summer morph]]
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.<ref name="ReferenceB" />

The main prey of the Arctic fox 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.<ref name="dx.doi.org">{{cite journal|last1=Pagh|first1=S. |last2=Hersteinsson|first2=P. |name-list-style=amp|title=Difference in diet and age structure of blue and white Arctic foxes (''Vulpes lagopus'') in the Disko Bay area, West Greenland|journal=Polar Research|date=2008|volume=27|issue=1|pages=44–51 |doi=10.1111/j.1751-8369.2008.00042.x|bibcode=2008PolRe..27...44P|s2cid=129105385|doi-access=free}}</ref><ref name="doi.org" /> 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.<ref name="doi.org" />

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 (biology)|order]] [[Carnivora]]).<ref>{{cite book|last=MacDonald|first=David W.|title=Biology and Conservation of Wild Canids|year=2004|publisher=Oxford University Press|isbn=978-0-19-851556-2}}</ref> The young emerge from the den when 3 to 4 weeks old and are weaned by 9 weeks of age.<ref name="NOAA" />

Arctic foxes are primarily [[Monogamy in animals|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]] 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]] in the fox.<ref name="doi.org" />

===Diet===
[[File:Fox with fish.jpg|thumb|An Arctic fox (summer morph) with [[salmon]]]]
Arctic foxes generally eat any small animal they can find, including [[lemming]]s, [[vole]]s, other rodents, [[hare]]s, [[bird]]s, [[Egg (food)|eggs]], fish, and [[carrion]]. They scavenge on carcasses left by larger predators such as wolves and [[polar bear]]s, and in times of scarcity also eat their [[feces]]. In areas where they are present, lemmings are their most common prey,<ref name="NOAA" /> 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]] 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 [[omnivore]]s.<ref name="Bockstoce2009">{{cite book|author=Bockstoce, J.R.|title=Furs and frontiers in the far north: the contest among native and foreign nations for the Bering Strait fur trade |year=2009 |url=https://books.google.com/books?id=HY6LvFMSxxwC&pg=PA41|publisher=Yale University Press |isbn=978-0-300-14921-0 |page=41}}</ref> This fox is a significant bird-egg predator, consuming eggs of all except the largest tundra bird species.<ref name="truett">{{cite book|editor1=Truett, J.C. |editor2=Johnson, S.R. |title=The natural history of an Arctic oil field: development and the biota |year=2000 |publisher=Academic Press |place=San Diego, San Francisco |isbn=978-0-12-701235-3 |chapter=Arctic Fox |pages=159–178 |author=Burgess, R. |chapter-url=https://books.google.com/books?id=ELsq-yAP0XkC&pg=PA161}}</ref>

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 {{cvt|3.5|kg}} would need 471 kJ/day during the winter to survive. In Canada, Arctic foxes acquire from [[snow goose]] 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.<ref>{{cite journal |last1=Careau|first1=V. |s2cid=51683546 |author2=Giroux, J.F. |author3=Gauthier, G. |author4=Berteaux, D. |name-list-style=amp |title=Surviving on cached foods — the energetics of egg-caching by Arctic foxes |journal=Canadian Journal of Zoology |date=2008 |volume=86|issue=10|pages=1217–1223 |doi=10.1139/Z08-102}}</ref>

==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 {{cvt|-70|°C}}. Among its [[adaptation]]s for survival in the cold is its dense, multilayered [[pelage]], which provides excellent insulation.<ref name="smith"/><ref>Claudio Sillero-Zubiri, Michael Hoffmann and David W. Macdonald (eds.) (2004). [http://www.carnivoreconservation.org/files/actionplans/canids.pdf Canids: Foxes, Wolves, Jackals and Dogs] {{webarchive|url=https://web.archive.org/web/20150923200655/http://www.carnivoreconservation.org/files/actionplans/canids.pdf |date=23 September 2015 }}. IUCN/SSC Canid Specialist Group.</ref> Additionally, the Arctic fox is the only canid whose foot pads are covered in fur. There are two genetically distinct coat color [[Polymorphism (biology)|morphs]]: white and blue.<ref name="ReferenceD"/> 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]] is dominant over the white allele, 99% of the Arctic fox population is the white morph.<ref name="doi.org"/><ref name="dx.doi.org"/> Two similar mutations to [[MC1R]] cause the blue color and the lack of seasonal color change.<ref name=Vage2005>{{cite journal | title = Two cysteine substitutions in the MC1R generate the blue variant of the arctic fox (Alopex lagopus) and prevent expression of the white winter coat | year = 2005| doi = 10.1016/j.peptides.2004.11.040| last1 = Våge| first1 = D.I.| last2=Fuglei| first2 = E.| last3 = Snipstad| first3 = K. | last4 = Beheim| first4 = J. | last5 = Landsem| first5 = V.M. |last6=Klungland| first6 = H. | journal = Peptides| volume = 26| issue = 10| pages = 1814–1817| pmid = 15982782| hdl = 11250/174384| s2cid = 7264542| hdl-access = free}}</ref> The fur of the Arctic fox provides the best insulation of any mammal.<ref name="ADAPT">{{cite web |url=http://pubs.aina.ucalgary.ca/arctic/arctic44-2-132.pdf|title=Adaptations by the arctic fox to the polar winter|access-date=2015-10-08|publisher=Arctic, vol.44 no.2|url-status=live|archive-url=https://web.archive.org/web/20160304201957/http://pubs.aina.ucalgary.ca/arctic/arctic44-2-132.pdf|archive-date=4 March 2016|df=dmy-all}}</ref>

The Arctic fox has a low [[surface area to volume ratio]], 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.<ref name="DECGNL">[http://www.env.gov.nl.ca/env/snp/programs/education/animal_facts/mammals/arctic_fox.html Arctic Fox ''Alopex lagopus''] {{webarchive|url=https://web.archive.org/web/20160305031515/http://www.env.gov.nl.ca/env/snp/programs/education/animal_facts/mammals/arctic_fox.html |date=5 March 2016 }}. Department of Environment and Conservation, Government of Newfoundland and Labrador</ref>

===Sensory modalities===
The Arctic fox has a functional [[hearing range]] between 125&nbsp;Hz–16&nbsp;kHz with a sensitivity that is ≤ 60&nbsp;dB in air, and an average peak sensitivity of 24&nbsp;dB at 4&nbsp;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.<ref>{{cite journal |last1=Stansbury|first1=A. |author2=Thomas, J.A. |name-list-style=amp |author3=Stalf, C.E. |author4= Murphy, L.D. |author5=Lombardi, D. |author6=Carpenter, J. |author7=Mueller, T. |title=Behavioral audiogram of two Arctic foxes (''Vulpes lagopus'') |journal=Polar Biology |date=2014|volume=37|issue=3|pages=417–422|doi=10.1007/s00300-014-1446-5|bibcode=2014PoBio..37..417S |s2cid=17154503}}</ref> The Arctic fox can easily hear lemmings burrowing under 4-5 inches of snow.<ref>{{cite book|last1=Perry|first1=Richard|title=The Polar Worlds|date=1973|publisher=Taplinger Pub. Co., Inc. |location=New York, New York|isbn=978-0800864057|pages=188 |edition=First |url=https://archive.org/details/polarworlds0000perr/page/188}}</ref> When it has located its prey, it pounces and punches through the snow to catch its prey.<ref name="DECGNL"/>

The Arctic fox also has a keen sense of smell. They can smell carcasses that are often left by polar bears anywhere from {{cvt|10|to|40|km}}. 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 {{cvt|46|–|77|cm}} of snow, and can detect a subnivean seal lair under {{cvt|150|cm}} of snow.<ref>{{cite journal |last1=Lai|first1=S. |last2=Bety|first2=J. |last3=Berteaux|first3=D. |name-list-style=amp |title=Spatio–temporal hotspots of satellite– tracked arctic foxes reveal a large detection range in a mammalian predator|journal=Movement Ecology |date=2015 |volume=3 |issue=37 |pages=37|doi=10.1186/s40462-015-0065-2|pmid=26568827|pmc=4644628 |bibcode=2015MvEco...3...37L |doi-access=free }}</ref>

===Physiology===
[[File:Arctic fox lying in grass - DPLA - 6bbdf7a6ee8c38192bcfad0a6f6dab84.jpg|left|thumb|Arctic fox lying in grass. A fox's thick winter coat helps keep its body temperature near {{cvt|100|F|order=flip}}. Foxes also have fur on the soles of their feet and reduced blood flow to their legs to help keep them warm.]]
The Arctic fox contains advantageous genes to overcome extreme cold and starvation periods. [[Transcriptome]] [[sequencing]] has identified two genes that are under [[positive selection]]: [[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.<ref name="ReferenceF">{{cite journal|last1=Kumar|first1=V. |author2=Kutschera, V.E. |author3=Nilsson, M.A. |author4=Janke, A. |name-list-style=amp |title=Genetic signatures of adaptation revealed from transcriptome sequencing of Arctic and red foxes |journal=BMC Genomics |date=2015 |volume=16 |issue=1 |pages=585 |doi=10.1186/s12864-015-1724-9 |pmid=26250829 |pmc=4528681 |doi-access=free }}</ref>

The average mass specific [[Basal metabolic rate|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 {{cvt|−7|C}} in the winter and {{cvt|5|C}} in the summer. It was commonly believed that the Arctic fox had a lower critical temperature below {{cvt|−40|C}}. However, some scientists have concluded that this statistic is not accurate since it was never tested using the proper equipment.<ref name="ReferenceC"/>

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.<ref name="ReferenceE"/> The [[thermal conductivity]] 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.<ref name="ReferenceC"/> Arctic foxes can constantly keep their feet above the tissue freezing point ({{cvt|−1|C}}) 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.<ref name="ReferenceE"/><ref name="ReferenceG">{{cite journal |last1=Henshaw|first1=R. |last2=Underwood|first2=L. |last3=Casey|first3=T. |title=Peripheral Thermoregulation: Foot Temperature in Two Arctic Canines |journal=Science |date=1972|volume=175 |issue=4025 |pages=988–990 |jstor=1732725 |bibcode=1972Sci...175..988H |doi=10.1126/science.175.4025.988 |pmid=5009400|s2cid=23126602}}</ref> 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.<ref name="ReferenceG"/>

==Size==
The average head-and-body length of the male is {{cvt|55|cm}}, with a range of {{cvt|46|to|68|cm}}, while the female averages {{cvt|52|cm}} with a range of {{cvt|41|to|55|cm}}.<ref name="smith"/><ref name="NG">{{cite web |url=http://animals.nationalgeographic.com/animals/mammals/arctic-fox/ |title=Arctic fox: ''Alopex lagopus'' |work=National Geographic |date=10 September 2010 |access-date=6 October 2014 |url-status=dead |archive-url=https://web.archive.org/web/20141006220541/http://animals.nationalgeographic.com/animals/mammals/arctic-fox |archive-date=6 October 2014 |df=dmy-all }}</ref> In some regions, no difference in size is seen between males and females. The tail is about {{cvt|30|cm}} long in both sexes. The height at the shoulder is {{cvt|25|to|30|cm}}.<ref>Boitani, L. (1984). ''Simon & Schuster's Guide to Mammals''. Simon & Schuster/Touchstone Books, {{ISBN|978-0-671-42805-1}}</ref> On average males weigh {{cvt|3.5|kg}}, with a range of {{cvt|3.2|to|9.4|kg}}, while females average {{cvt|2.9|kg}}, with a range of {{cvt|1.4|to|3.2|kg}}.<ref name="smith">''Alopex lagopus'' at the [http://www.mnh.si.edu/mna/image_info.cfm?species_id=2 Smithsonian] {{webarchive|url=https://web.archive.org/web/20150313001124/http://www.mnh.si.edu/mna/image_info.cfm?species_id=2 |date=13 March 2015 }}</ref>

==Taxonomy==
''Vulpes lagopus'' is a 'true fox' belonging to the genus ''[[Vulpes]]'' of the fox [[tribe (biology)|tribe]] [[Vulpini]], which consists of 12 extant species.<ref name="ReferenceF"/> It is classified under the [[subfamily (biology)|subfamily]] [[Caninae]] of the canid [[family (biology)|family]] [[Canidae]]. Although it has previously been assigned to its own [[Monotypic taxon|monotypic]] [[genus]] ''Alopex'', recent [[genetics|genetic]] evidence now places it in the genus ''Vulpes'' along with the majority of other foxes.<ref name=msw3/><ref name=complete>{{cite journal|title=Building large trees by combining phylogenetic information: a complete phylogeny of the extant Carnivora (Mammalia)|journal=Biological Reviews |year=1999|first=O.R.P. |last=Bininda-Emonds |author2=Gittleman, J.L. |name-list-style=amp |author3=Purvis, A. |volume=74|issue=2|pages=143–175 |url=https://www.researchgate.net/publication/227622637 |doi=10.1017/S0006323199005307 |doi-broken-date=31 January 2024 |pmid=10396181 |citeseerx=10.1.1.328.7194 |url-status=live|archive-url=https://web.archive.org/web/20140415181742/http://www.researchgate.net/publication/227622637_Building_large_trees_by_combining_phylogenetic_information_a_complete_phylogeny_of_the_extant_Carnivora_(Mammalia)|archive-date=15 April 2014|df=dmy-all}}</ref>

{{clade | style = font-size: 90%;line-height:50%
   |1={{clade
      |1={{clade
         |1={{clade
            |1={{clade
               |1={{clade
                  |1={{clade
                     |1={{clade
                        |1='''Arctic fox'''<ref name="lindblad-toh2005">{{Cite journal | last1 = Lindblad-Toh | first1 = K. |last2 = Wade | first2 = C. M. | last3 = Mikkelsen | first3 = T. S. | last4 = Karlsson | first4 = E. K. | last5 = Jaffe |first5=D. B. | last6 = Kamal | first6 = M. | last7 = Clamp | first7 = M. | last8 = Chang | first8 = J. L. |last9=Kulbokas |first9 = E. J. | last10 = Zody | doi = 10.1038/nature04338 | first10 = M. C. | last11 = Mauceli | first11 = E. |last12=Xie | first12 = X. | last13 = Breen | first13 = M. | last14 = Wayne | first14 = R. K. | last15=Ostrander |first15=E. A. | last16 = Ponting | first16 = C. P. | last17 = Galibert | first17 = F. | last18 = Smith |first18 = D. R. |last19=Dejong | first19 = P. J. | last20 = Kirkness | first20 = E. | last21 = Alvarez | first21 = P. |last22 = Biagi |first22=T. | last23 = Brockman | first23 = W. | last24 = Butler | first24 = J. | last25 = Chin | first25 = C. W. |last26=Cook | first26 = A. | last27 = Cuff | first27 = J. | last28 = Daly | first28 = M. J. | last29 = Decaprio |first29=D. |last30 = Gnerre | first30 = S. | display-authors = 1 |title=Genome sequence, comparative analysis and haplotype structure of the domestic dog |journal = Nature | volume = 438 | issue = 7069 | pages = 803–819 | year = 2005 |pmid=16341006 | bibcode = 2005Natur.438..803L | doi-access = free}}</ref>{{rp|at=Fig. 10}}
                        |2=[[Kit fox]]
                        }}
                     |2=[[Swift fox]]<ref name="audet"/>
                     }}
                  |2={{clade
                     |1=[[Corsac fox]]
                     |2={{clade
                        |1=[[Rüppell's fox]]
                        |2=[[Red fox]]
                        }}
                     }}
                  }}
               |2=[[Cape fox]]
               }}
            |2={{clade
               |1=[[Blanford's fox]]
               |2=[[Fennec fox]]
               }}
            }}
         |2=[[Raccoon dog]]
         }}
      |2={{clade
         |1=[[Bat-eared fox]]
         }}
      }}
}}

It was originally described by [[Carl Linnaeus]] in the [[10th edition of Systema Naturae|10th edition of ''Systema Naturae'']] in 1758 as ''Canis lagopus''. The [[type specimen]] was recovered from [[Lapland (Sweden)|Lapland]], [[Sweden]]. The generic name ''vulpes'' is [[Latin]] for "fox".<ref name="lariviere">{{cite journal|author=Larivière, S. |year=2002|title=''Vulpes zerda''|journal=Mammalian Species |pages=1–5 |url=http://www.science.smith.edu/departments/Biology/VHAYSSEN/msi/pdf/714_Vulpes_zerda.pdf|doi=10.1644/1545-1410(2002)714<0001:VZ>2.0.CO;2|issue=714|s2cid=198968737 |url-status=live|archive-url=https://web.archive.org/web/20111223193851/http://www.science.smith.edu/departments/Biology/VHAYSSEN/msi/pdf/714_Vulpes_zerda.pdf|archive-date=23 December 2011|df=dmy-all}}</ref> The specific name ''lagopus'' is derived from [[Ancient Greek]] λαγώς (''lagōs'', "[[hare]]") and πούς (''pous'', "foot"), referring to the hair on its feet similar to those found in cold-climate species of hares.<ref name="audet">{{cite journal|author1=Audet, A.M. |author2=Robbins, C.B. |author3=Larivière, S. |name-list-style=amp |year=2002|title=''Alopex lagopus''|journal=Mammalian Species |issue=713 |pages=1–10 |url=http://www.science.smith.edu/departments/Biology/VHAYSSEN/msi/pdf/713_Alopex_lagopus.pdf|doi=10.1644/1545-1410(2002)713<0001:AL>2.0.CO;2|s2cid=198969139 |url-status=live|archive-url=https://web.archive.org/web/20110608042809/http://www.science.smith.edu/departments/Biology/VHAYSSEN/msi/pdf/713_Alopex_lagopus.pdf|archive-date=8 June 2011|df=dmy-all}}</ref>

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.<ref name="ReferenceF"/>

===Origins===
The origins of the Arctic fox have been described by the "out of Tibet" hypothesis. On the [[Tibetan Plateau]], [[fossil]]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]] (5.3–2.6 MYA). It is believed that this ancient fox is the ancestor of the modern Arctic fox. Globally, the Pliocene was about 2–3&nbsp;°C warmer than today, and the Arctic during the summer in the mid-Pliocene was 8&nbsp;°C warmer. By using stable carbon and oxygen [[isotope]] 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|Pleistocene Epoch]] (2.6 million-11,700 years ago).<ref>{{cite journal|last1=Wang|first1=X. |author2=Wang, Y. |name-list-style=amp |author3=Li, Q. |author4=Tseng, Z.J. |author5=Takeuchi, G.T. |author6=Deng, T. |author7=Xie, G. |author8=Chang, M.M. |author9=Wang, N. |title=Cenozoic vertebrate evolution and paleoenvironment in Tibetan Plateau: Progress and prospects |journal=Gondwana Research |date=2015 |volume=27 |issue=4|pages=1335–1354 |doi=10.1016/j.gr.2014.10.014 |bibcode=2015GondR..27.1335W}}</ref>

===Subspecies===
[[File:Blue fox on St Paul Island by Ryan Mong USFWS.jpg|thumb|Blue phase, Pribilof Islands]]
Besides the nominate [[subspecies]], the common Arctic fox, ''V. l. lagopus'', four other subspecies of this fox have been described:
* [[Bering Sea#Islands|Bering]] Islands Arctic fox, ''V. l. beringensis''
* Greenland Arctic fox, ''V. l. foragoapusis''
* Iceland Arctic fox, ''V. l. fuliginosus''
* [[Pribilof Islands]] Arctic fox, ''V. l. pribilofensis''

==Distribution and habitat==
[[Image:ArcticFoxesLyd.jpg|thumb|The Arctic fox's seasonal furs, summer (top), "blue" (middle), and winter (bottom)]]
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]] (where it was hunted to extinction)<ref>[https://web.archive.org/web/20180521021903/https://www.hurtigruten.us/must-read-articles/spitsbergen/the-isolated-beauty-of-jan-mayen/ The isolated beauty of Jan Mayen]. Hurtigruten US</ref> and other islands in the [[Barents Sea]], northern Russia, islands in the [[Bering Sea]], [[Alaska]], and Canada as far south as [[Hudson Bay]]. In the late 19th century, it was introduced into the [[Aleutian Islands]] southwest of Alaska. However, the population on the Aleutian Islands is currently being eradicated in conservation efforts to preserve the local bird population.<ref name=iucn /> It mostly inhabits tundra and [[pack ice]], but is also present in Canadian [[taiga|boreal forest]]s (northeastern [[Alberta]], northern [[Saskatchewan]], northern [[Manitoba]], [[Northern Ontario]], [[Nord-du-Québec|Northern Quebec]], and [[Newfoundland and Labrador]])<ref>[http://www.natureconservancy.ca/en/what-we-do/resource-centre/featured-species/mammals/arctic-fox.html Arctic fox]. Nature Conservancy Canada</ref> and the [[Kenai Peninsula]] in Alaska. They are found at elevations up to {{cvt|3000|m}} above sea level and have been seen on sea ice close to the [[North Pole]].<ref name=Feldhamer>{{cite book |author1=Feldhamer, George A. |author2=Thompson, B.C. |author3=Chapman, J.A. |title=Wild Mammals of North America: Biology, Management, and Conservation |url=https://books.google.com/books?id=-xQalfqP7BcC&pg=PA540 |year=2003 |publisher=JHU Press |isbn=978-0-8018-7416-1 |pages=511–540}}</ref>

The Arctic fox is the only land mammal native to Iceland.<ref name="Iceland">{{cite web |url=http://www.iww.is/pages/alife/biglf.html |title=Wildlife |year=2000 |work=Iceland Worldwide |publisher=iww.is |access-date=22 April 2010 |archive-url=https://web.archive.org/web/20100414112114/http://www.iww.is/pages/alife/biglf.html |archive-date=14 April 2010 |url-status=dead |df=dmy }}</ref> It came to the isolated [[Atlantic Ocean|North Atlantic]] island at the end of the [[Last glacial period|last ice age]], walking over the frozen sea. [[The Arctic Fox Center]] in [[Súðavík]] contains an exhibition on the Arctic fox and conducts studies on the influence of tourism on the population.<ref>{{cite web |url=http://www.arcticfoxcenter.com/ |title=The Arctic Fox Center |access-date=19 May 2011 |url-status=live |archive-url=https://web.archive.org/web/20110210085613/http://arcticfoxcenter.com/ |archive-date=10 February 2011 |df=dmy-all }}</ref> Its range during the last [[ice age]] was much more extensive than it is now, and [[fossil]] remains of the Arctic fox have been found over much of northern Europe and Siberia.<ref name=iucn />

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.<ref name="dx.doi.org"/>

<gallery widths="200px" heights="145px">
Image:Iceland-1979445.jpg|Arctic fox in winter pelage, [[Iceland]]
Image:Fjellrev pho.jpg|Arctic fox
</gallery>

===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.<ref name="ReferenceA">{{cite journal |last1=Lai|first1=S. |last2=Bety|first2=J. |last3=Berteaux|first3=D. |title=Movement tactics of a mobile predator in a meta-ecosystem with fluctuating resources: the arctic fox in the High Arctic |journal=Oikos |date=2017|volume=126|issue=7|pages=937–947|doi=10.1111/oik.03948|bibcode=2017Oikos.126..937L }}</ref>

In July 2019, the [[Norwegian Polar Institute]] reported the story of a yearling female which was fitted with a [[GPS]] tracking device and then released by their researchers on the east coast of [[Spitsbergen]] in the [[Svalbard]] group of islands.<ref>{{Cite news|url=https://www.nytimes.com/2019/07/02/world/europe/arctic-fox-norway-canada.html |archive-url=https://ghostarchive.org/archive/20220101/https://www.nytimes.com/2019/07/02/world/europe/arctic-fox-norway-canada.html |archive-date=2022-01-01 |url-access=limited|title=An Arctic Fox's Epic Journey: Norway to Canada in 76 Days |last=Specia|first=M. |date=2019 |work=The New York Times|access-date=2019-07-02|language=en-US|issn=0362-4331}}{{cbignore}}</ref> The young fox crossed the polar ice from the islands to [[Greenland]] in 21 days, a distance of {{cvt|1,512|km}}. She then moved on to [[Ellesmere Island]] in northern [[Canada]], covering a total recorded distance of {{cvt|3,506|km}} in 76 days, before her [[GPS tracker]] stopped working. She averaged just over {{cvt|46|km}} a day, and managed as much as {{cvt|155|km}} in a single day.<ref name="bbcepic">{{cite news |title=Scientists 'speechless' at Arctic fox's epic trek |work=BBC News |date=July 2019 |url=https://www.bbc.com/news/blogs-news-from-elsewhere-48824181 |access-date=1 July 2019 |ref=bbcepic}}</ref>

==Conservation status==
[[File:Lagopusskull.jpg|thumb|left|Drawing of skull by [[St. George Mivart]], 1890]]
The Arctic fox has been assessed as [[least concern]] on the [[IUCN Red List]] since 2004.<ref name=iucn /> 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.<ref name=NOAA/> Of these, especially in Finland, the Arctic fox is even classified as [[Critically Endangered|critically endangered]],<ref>{{cite web| title= Naali ''Alopex lagopus''. | date= 2011-08-01 | publisher= Metsähallitus |url=http://www.metsa.fi/sivustot/metsa/fi/Luonnonsuojelu/Lajitjaluontotyypit/Uhanalaisetelaimet/Naali/Sivut/Naali.aspx |archive-url=https://web.archive.org/web/20111214233500/http://www.metsa.fi/sivustot/metsa/fi/Luonnonsuojelu/Lajitjaluontotyypit/Uhanalaisetelaimet/Naali/Sivut/Naali.aspx |archive-date=2011-12-14  | access-date = 2022-08-11 | language = fi}}</ref> because even though the animal was declared a protected species in Finland in 1940, the population has not recovered despite that.<ref>{{cite book| author= Olli Järvinen & Kaarina Miettinen | title= Sammuuko suuri suku? – Luonnon puolustamisen biologiaa | pages= 95, 190 | location= Vantaa | publisher= Suomen luonnonsuojelun tuki | year= 1987 | isbn= 951-9381-20-1 | language = fi}}</ref> 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]]s (a 3- to 4-year cycle).<ref name=truett/> The populations are especially vulnerable during the years when the prey population crashes, and uncontrolled [[Animal trapping|trapping]] has almost eradicated two subpopulations.<ref name=NOAA>{{cite web |url=http://www.arctic.noaa.gov/report12/arctic_fox.html |title=Arctic fox (''Vulpes lagopus'') |author1=Angerbjörn, A. |author2=Berteaux, D. |author3=I.R. |date=2012 |work=Arctic report card: Update for 2012 |publisher=NOAA Arctic Research Program |access-date=6 October 2014 |url-status=live |archive-url=https://web.archive.org/web/20141011195501/http://www.arctic.noaa.gov/report12/arctic_fox.html |archive-date=11 October 2014 |df=dmy-all }}</ref>

[[File:Alopex lagopus 05 MWNH 289.JPG|thumb|Skull]]

The pelts of Arctic foxes with a slate-blue coloration were especially valuable. They were transported to various previously fox-free [[Aleutian Island]]s during the 1920s. The program was successful in terms of increasing the population of blue foxes, but their predation of [[Aleutian cackling goose|Aleutian Canada geese]] conflicted with the goal of preserving that species.<ref>{{cite book|url=https://books.google.com/books?id=sbYL7JNnMNIC&pg=PA42|page=42|title=Ecology of North America|author=Bolen, Eric G. |publisher=[[John Wiley and Sons]]|year=1998|isbn=978-0-471-13156-4}}</ref>

The Arctic fox is losing ground to the larger [[red fox]]. This has been attributed to [[climate change]]—the camouflage value of its lighter coat decreases with less snow cover.<ref name="Hannah2010">{{cite book|author=Hannah, Lee|title=Climate Change Biology|url=https://books.google.com/books?id=4Vvqw2gdk9QC&pg=PA63|year=2010|publisher=Academic Press|isbn=978-0-12-374182-0|page=63}}</ref> Red foxes dominate where their ranges begin to overlap by killing Arctic foxes and their kits.<ref name="MacdonaldSillero-Zubiri2004">{{cite book|author1=Macdonald, David Whyte|author2=Sillero-Zubiri, Claudio|title=The biology and conservation of wild canids|url=https://books.google.com/books?id=Vrgow9ERQeIC&pg=PA10|year=2004|publisher=Oxford University Press|isbn=978-0-19-851556-2|page=10}}</ref> 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]] in much of its former range, the red fox population has grown larger, and it has taken over the niche of [[Apex predator|top predator]].<ref>{{GBIF |taxon=''Vulpes lagopus'' (Linnaeus, 1758) |id=113392918 |access-date=2024-02-21}}</ref> 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.<ref name=G_and_E>{{cite book |author1=Garrott, R. A.  |author2=Eberhardt, L. E. | year = 1987 | chapter = Arctic fox | editor = Novak, M. | title = Wild furbearer management and conservation in North America | pages = 395–406|publisher=Ontario Trappers Association |isbn=978-0774393652|display-editors=etal}}</ref> 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.<ref name=Tannerfeldt>{{cite book | author = Tannerfeldt, M. | year = 1997 | title = Population fluctuations and life history consequences in the Arctic fox. | publisher = Dissertation, Stockholm University | location = Stockholm, Sweden}}</ref>

The world population of Arctic foxes is thus not endangered, but two Arctic fox subpopulations are. One is on [[Medny Island]] ([[Commander Islands]], Russia), which was reduced by some 85–90%, to around 90 animals, as a result of [[mange]] caused by an ear tick introduced by dogs in the 1970s.<ref name=Goltsman>{{cite journal | author = Goltsman, M.| year = 1996 | last2 = Kruchenkova | first2 = E. P. | last3 = MacDonald | first3 = D. W. | title = The Mednyi Arctic foxes: treating a population imperilled by disease | journal = Oryx | volume = 30 | pages = 251–258 | doi = 10.1017/S0030605300021748 | issue = 4| doi-access = free }}</ref> 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]]). 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.<ref name="Lönnberg">{{cite book | author = Lönnberg, E. | year = 1927 | title = Fjällrävsstammen i Sverige 1926 | publisher = Royal Swedish Academy of Sciences | location = Uppsala, Sweden}}</ref> The population has remained at a low density for more than 90 years, with additional reductions during the last decade.<ref name="Angerbjörn">{{cite journal | year = 1995 | title = Dynamics of the Arctic fox population in Sweden | journal = Annales Zoologici Fennici | volume = 32 | pages = 55–68 | url = http://su.diva-portal.org/smash/record.jsf?pid=diva2:234717 | author = Angerbjörn, A. | display-authors = etal | url-status = live | archive-url = https://web.archive.org/web/20140224040113/http://su.diva-portal.org/smash/record.jsf?pid=diva2:234717 | archive-date = 24 February 2014 | df = dmy-all }}</ref> 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.<ref name=Tannerfeldt/>

The Arctic fox is classed as a "prohibited new organism" under New Zealand's [[Hazardous Substances and New Organisms Act 1996]], preventing it from being imported into the country.<ref>{{Cite web|url=http://legislation.govt.nz/act/public/1996/0030/latest/DLM386556.html#DLM386556|title=Hazardous Substances and New Organisms Act 2003 – Schedule 2 Prohibited new organisms|publisher=New Zealand Government|access-date=26 January 2012|url-status=live|archive-url=https://web.archive.org/web/20120616104517/http://legislation.govt.nz/act/public/1996/0030/latest/DLM386556.html#DLM386556|archive-date=16 June 2012|df=dmy-all}}</ref>

==See also==
* [[Arctic rabies virus]]

==References==
{{Reflist|30em}}

==Further reading==
* Nowak, Ronald M. (2005). ''Walker's Carnivores of the World''. Baltimore: Johns Hopkins Press. {{ISBN|0-8018-8032-7}}.

==External links==
{{Commons}}
{{Wikispecies|Vulpes lagopus}}
* [https://archive.today/20120523215629/http://www.environment.no/Topics/Biological-diversity/Threatened-species/Arctic-fox/ State of the Environment Norway: Arctic fox]
* [http://www.mnh.si.edu/mna/image_info.cfm?species_id=2 Smithsonian Institution – North American Mammals: Vulpes lagopus]
* [https://web.archive.org/web/20140225045357/http://www.islandsmyndir.is/html_skjol/annad/Dyr/Arctic_Fox_cub/index.html Photo Gallery by islandsmyndir.is]
* {{SealifePhotos|404130}}
* https://www.britannica.com/animal/Arctic-fox

{{Carnivora|Ca.}}
{{Taxonbar|from=Q82738}}
{{Authority control}}

[[Category:Arctic land animals|Fox, arctic]]
[[Category:Holarctic fauna]]
[[Category:Mammals described in 1758]]
[[Category:Mammals of Europe]]
[[Category:Mammals of Asia]]
[[Category:Mammals of Greenland]]
[[Category:Mammals of Iceland]]
[[Category:Mammals of North America]]
[[Category:Mammals of Russia]]
[[Category:Mammals of Canada]]
[[Category:Mammals of the United States]]
[[Category:Mammals of the Arctic]]
[[Category:Taxa named by Carl Linnaeus]]
[[Category:Vulpes]]
[[Category:Habitats Directive species]]