Arctic fox

The Arctic fox (Vulpes lagopus), also known as the white fox, polar fox, or snow fox, is a small fox native to the Arctic regions of the Northern Hemisphere and common throughout the Arctic tundra biome.[1][7][8] It is well adapted to living in cold environments, and is best known for its thick, warm fur that is also used as camouflage. On average, Arctic foxes only live 3–4 years in the wild.[9] Its body length ranges from 46 to 68 cm (18 to 27 in), with a generally rounded body shape to minimize the escape of body heat.

The Arctic fox preys on many small creatures such as lemmings, voles, ringed seal pups, fish, waterfowl, and seabirds. 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 eagles,[10] polar bears,[11] wolverines, red foxes, wolves, and grizzly bears.[12][13]

Arctic fox
Iceland-1979445 (cropped 3)
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Canidae
Genus: Vulpes
Species:
V. lagopus
Binomial name
Vulpes lagopus
Cypron-Range Vulpes lagopus
Arctic fox range
Synonyms[3][4][5][6]

Behavior

Arctic foxes must endure a temperature difference of up to 90-100 °C between the external environment and their internal core temperature.[14] 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.[15][14] Although the Arctic fox is active year-round and do not hibernate, they attempt to preserve fat by reducing their locomotor activity.[15][16] 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 .[17]

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 1,000 m2 (1,200 sq yd) and are often in eskers, long ridges of sedimentary material deposited in formerly glaciated regions. These dens may be in existence for many decades and are used by many generations of foxes.[17]

Fox pups animals
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.[12]

The main prey in the tundra is 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.[18][13] 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.[13]

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).[19] The young emerge from the den when 3 to 4 weeks old and are weaned by 9 weeks of age.[17]

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 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.[13]

Diet

Fox with fish
An Arctic fox (Summer morph) with fish

Arctic foxes generally eat any small animal they can find, including lemmings, voles, other rodents, hares, birds, eggs, fish, and carrion. They scavenge on carcasses left by larger predators such as wolves and polar bears, and in times of scarcity even eat their feces. In areas where they are present, lemmings are their most common prey,[17] 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 omnivores.[20] This fox is a significant bird-egg predator, consuming eggs of all except the largest tundra bird species.[21] When food is overabundant, the Arctic fox buries (caches) the surplus as a reserve.

Arctic foxes survive harsh winters and food scarcity by either hoarding food or storing body fat. Fat is deposited subcutaneously and viscerally in Arctic foxes. At the beginning of winter, the foxes have approximately 14740 kJ of energy storage from fat alone. Using the lowest BMR value measured in Arctic foxes, an average sized fox (3.5 kg) would need 471 kJ/day during the winter to survive. Arctic foxes can acquire goose eggs (from greater snow geese in Canada) at a rate of 2.7–7.3 eggs/h, and they 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). Researchers have also noted that some eggs stored in the summer are accessed later the following spring prior to reproduction.[22]

Adaptations

Alopex lagopus IMG 9019
A sleeping Arctic fox with its tail wrapped around itself

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 −70 °C (−94 °F). Among its adaptations for survival in the cold is its dense, multilayered pelage, which provides excellent insulation.[23][24] 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.[15] 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.[13][18] The fur of the Arctic fox provides the best insulation of any mammal.[25]

The 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.[26]

Sensory modalities

The Arctic fox has a functional hearing range 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.[27] The Arctic fox can easily hear lemmings burrowing under 4-5 inches of snow.[28] When it has located its prey, it pounces and punches through the snow to catch its victim. [26]

The Arctic fox also has a keen sense of smell. They can smell carcasses that are often left by polar bears anywhere from 10–40 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 46–77 cm of snow, and can detect a subnivean seal lair under 150 cm of snow.[29]

Physiology

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.[30]

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 −7 °C in the winter and 5 °C in the summer. It was commonly believed that the Arctic fox had a lower critical temperature below −40 °C. However, some scientists have concluded that this stat is not accurate since it was never tested using the proper equipment.[14]

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.[16] 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.[14] Arctic foxes can constantly keep their feet above the tissue freezing point (−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.[16][31] 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.[31]

Size

The average head-and-body length of the male is 55 cm (22 in), with a range of 46 to 68 cm (18 to 27 in), while the female averages 52 cm (20 in) with a range of 41 to 55 cm (16 to 22 in).[23][32] In some regions, no difference in size is seen between males and females. The tail is about 30 cm (12 in) long in both sexes. The height at the shoulder is 25 to 30 cm (9.8 to 11.8 in).[33] On average males weigh 3.5 kg (7.7 lb), with a range of 3.2 to 9.4 kg (7.1 to 20.7 lb), while females average 2.9 kg (6.4 lb), with a range of 1.4 to 3.2 kg (3.1 to 7.1 lb).[23]

Taxonomy

Vulpes lagopus is a 'true fox' belonging to the genus Vulpes of the fox tribe Vulpini, which consists of 12 extant species.[30] It is classified under the subfamily Caninae of the canid family Canidae. Although it has previously been assigned to its own monotypic genus Alopex, recent genetic evidence now places it in the genus Vulpes along with the majority of other foxes.[7][34]

Arctic fox[35](Fig. 10)

Kit fox

Swift fox[36]

Corsac fox

Rüppell's fox

Red fox

Cape fox

Blanford's fox

Fennec fox

Raccoon dog

Bat-eared fox

It was originally described by Carl Linnaeus in the 10th edition of Systema Naturae in 1758 as Canis lagopus. The type specimen was recovered from Lapland, Sweden. The generic name vulpes is Latin for "fox".[37] 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.[36]

Looking at the most recent phylogeny, the Arctic fox diverged from the domesticated dog (Canis lupus familiaris) at approximately 12 MYA. 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.[30]

Origins

The origins of the Arctic fox have been described by the “out of Tibet” hypothesis. On the Tibetan Plateau, fossils 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 °C warmer than today, and the Arctic during the summer in the mid-Pliocene was 8 °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 Epoch (2.6 million-11,700 years ago).[38]

Subspecies

Blue fox on St Paul Island by Ryan Mong USFWS
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 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

ArcticFoxesLyd
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)[39] 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.[1] It mostly inhabits tundra and pack ice, but is also present in Canadian boreal forests (northeastern Alberta, northern Saskatchewan, northern Manitoba, Northern Ontario, Northern Quebec, and Newfoundland and Labrador)[40] and the Kenai Peninsula in Alaska. They are found at elevations up to 3,000 m (9,800 ft) above sea level and have been seen on sea ice close to the North Pole.[41]

The Arctic fox is the only land mammal native to Iceland.[42] 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 contains an exhibition on the Arctic fox and conducts studies on the influence of tourism on the population.[43] 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.[1]

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.[18]

Iceland-1979445

Arctic fox in winter pelage, Iceland

Fjellrev pho

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.[9]

Conservation status

Lagopusskull
Drawing of skull by St. George Mivart, 1890

The conservation status of the species is in general good and several hundred thousand individuals are estimated to remain in total. The IUCN has assessed it as being of "least concern".[1] 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.[17] 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 voles (a 3- to 4-year cycle).[21] The populations are especially vulnerable during the years when the prey population crashes, and uncontrolled trapping has almost eradicated two subpopulations.[17]

Alopex lagopus 05 MWNH 289
Skull

The pelts of Arctic foxes with a slate-blue coloration were especially valuable. They were transported to various previously fox-free Aleutian Islands 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.[44]

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.[45] Red foxes dominate where their ranges begin to overlap by killing Arctic foxes and their kits.[46] 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 top predator. 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.[47] 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.[48]

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.[49] 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.[50] The population has remained at a low density for more than 90 years, with additional reductions during the last decade.[51] 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.[48]

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.[52]

See also

References

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  44. ^ Bolen, Eric G. (1998). Ecology of North America. John Wiley and Sons. p. 42. ISBN 978-0-471-13156-4.
  45. ^ Hannah, Lee (2010). Climate Change Biology. Academic Press. p. 63. ISBN 978-0-12-374182-0.
  46. ^ Macdonald, David Whyte; Sillero-Zubiri, Claudio (2004). The biology and conservation of wild canids. Oxford University Press. p. 10. ISBN 978-0-19-851556-2.
  47. ^ Garrott, R. A.; Eberhardt, L. E. (1987). "Arctic fox". In Novak, M.; et al. Wild furbearer management and conservation in North America. pp. 395–406. ISBN 978-0774393652.
  48. ^ a b Tannerfeldt, M. (1997). Population fluctuations and life history consequences in the Arctic fox. Stockholm, Sweden: Dissertation, Stockholm University.
  49. ^ Goltsman, M.; Kruchenkova, E. P.; MacDonald, D. W. (1996). "The Mednyi Arctic foxes: treating a population imperilled by disease". Oryx. 30 (4): 251–258. doi:10.1017/S0030605300021748.
  50. ^ Lönnberg, E. (1927). Fjällrävsstammen i Sverige 1926. Uppsala, Sweden: Royal Swedish Academy of Sciences.
  51. ^ Angerbjörn, A.; et al. (1995). "Dynamics of the Arctic fox population in Sweden". Annales Zoologici Fennici. 32: 55–68. Archived from the original on 24 February 2014.
  52. ^ "Hazardous Substances and New Organisms Act 2003 – Schedule 2 Prohibited new organisms". New Zealand Government. Archived from the original on 16 June 2012. Retrieved 26 January 2012.

Further reading

  • Nowak, Ronald M. (2005). Walker's Carnivores of the World. Baltimore: Johns Hopkins Press. ISBN 0-8018-8032-7.

External links

Arcticfox

Arcticfox is a 1986 science fiction tank simulation video game developed by Dynamix and published by Electronic Arts. It was published in Europe by Ariolasoft. A sequel to Dynamix's Stellar 7, Arcticfox was developed for the Amiga as one of the platform's first titles but was quickly ported to other platforms including the Atari ST, Commodore 64, ZX Spectrum, MS-DOS and Apple II. A third game was released in the series in 1991 titled Nova 9: The Return of Gir Draxon.

The game is set in a fictional 2005 where aliens have taken over Antarctica in an attempt to steal the Earth's oxygen. The player is sent to eradicate the intruders using a new super tank codenamed Arcticfox.

Arcticfox's design team at Dynamix also went on to produce The Incredible Machine and Red Baron.

Barrow Strait

Barrow Strait is a shipping waterway in Northern Canada's territory of Nunavut. Forming part of the Parry Channel, the strait separates several large islands including Cornwallis Island and Devon Island to the north, from Prince of Wales Island, Somerset Island, and Prince Leopold Island to the south.

The first 30 mi (48 km) of its eastern section has no islands, commonly does not freeze until the end of November, nor consolidate until the end of December. Garrett Island, Lowther Island, Young Island, Hamilton Island, and Russell Island lay south of Bathurst Island. Browne Island, Somerville Island, and Griffith Island lay southwest of Cornwallis Island. Beechy Island lays off of Devon Island.

From its eastern junction with Lancaster Sound to its western junction with Viscount Melville Sound, the strait measures 170 mi (270 km) long. Its eastern mouth, between Prince Leopold Island, and Cape Hurd on Devon Island, is 28 mi (45 km) wide. Its western mouth, at Cape Cockburn, southwestern Bathurst Island, is 66 mi (106 km) wide.Habitat for Arctic fox, birds, polar bear, ringed seal, and whales is located along the ice edge, near Leopold Island, while consolidated ice in the strait's central and western sections provides a bridge for caribou crossing.A strategic waterway from deepwater vessels navigating Arctic waters, the Strait was surveyed in detail by the Soviet Navy during the Cold War.

Grey Goose Island

Grey Goose Island is one of several, larger, uninhabited Canadian arctic islands in Nunavut, Canada located within the midsection of James Bay. Other comparable islands in the area include the Bear Islands, North and South Twin Islands, Spencer Island, Sunday Island, and Walter Island. La Grande River and the Cree village of Chisasibi, Quebec are 65 km (40 mi) to the southeast.The island is low-lying and flat, dominated by rock and sand. It is devoid of trees, although there are grasses and other hardy plants. It is frequented by Arctic fox, Ringed seal, Beluga whale, caribou, and polar bears. A major migration route for geese, notable bird populations include American pipit, Arctic tern, black guillemot, common eider, common loon, great black-backed gull, gyrfalcon, herring gull, Pacific loon, purple sandpiper, red-necked phalarope, red-throated loon, and semipalmated plover.

Järvzoo

Järvzoo is a well-known zoo in Järvsö, Sweden, which has a large collection of Nordic animals. These include the major carnivores of Sweden: the wolf, arctic fox, bear, lynx, and wolverine, as well as moose, roe deer, reindeer, Finnish forest reindeer, and several species of birds.

Komandorsky Nature Reserve

Komandorsky Nature Reserve (Russian: Командо́рский госуда́рственный биосфе́рный запове́дник) is a zapovednik (nature reserve) located on the Commander Islands, Kamchatka Krai, Russia.

The total area of the preserve is 3,648,679 ha (36,648 km2) of which 2,177,398 ha (21,774 km2) are marine buffer zone. The land territory includes most of Bering Island, all of Medny Island, as well as thirteen smaller islands and rocks. It was created in 1993 to protect the diverse ecosystems of the Commander Islands and the surrounding marine waters of the Bering Sea and northern Pacific Ocean.

Because of its isolation and the high productivity of the Bering Sea and the Pacific continental shelf, the reserve is marked by a great diversity of animal life. It is a refuge for over a million seabirds, several hundred thousand northern fur seals, several thousand Steller's sea lions, common seals, and spotted seals, a healthy population of sea otter, some 21 whale species, two rare endemic subspecies of Arctic fox, and many endangered or threatened migratory birds, such as the whooper swan, Steller's eider, and Steller's sea eagle. Furthermore, it is biogeographically unique stepping stone between Asian and North American flora and fauna.

Fishing is entirely prohibited within the 50 km (31 mi) buffer zone surrounding the preserve.

An additional stated purpose of the preserve is to foster the ecologically and culturally sustainable development of the only inhabited settlement on the Commander Islands, the village of Nikolskoye (pop. approximately 750 as of 2007).

The site is being prepared for inscription to the World Heritage List.

Lierne National Park

Lierne National Park (Norwegian: Lierne nasjonalpark) lies in the municipality of Lierne in Trøndelag county, Norway. The 333-square-kilometre (129 sq mi) park was established on 17 December 2004 by a royal resolution. The park covers 333 square kilometres (129 sq mi) of land along the border with Sweden. The park lies east of the populated areas in Lierne, about 12 kilometres (7.5 mi) southeast of the village of Sandvika and about 6 kilometres (3.7 mi) northeast of the village of Mebygda.

The park is dominated by a large mountainous region rich in lynx, wolverines, bears, and wildfowl. The rare Arctic fox also live in the area. Much of the land was formed during the last Ice Age. There are many peaks over 1,000 metres (3,300 ft) above sea level, the highest of which is Hestkjøltopp at 1,390 metres (4,560 ft). There are many wetland areas with large swamps and open woodlands.

List of museums in Iceland

This is a list of museums in Iceland.

Akranes Folk Museum

Akureyri Art Museum

Árbæjarsafn

Aviation Museum of Iceland

Borgarnes Museum Safnahús Borgarfjarðar

Center for Icelandic Art

Duus Museum

Galleri Sudurgata 7

Gljúfrasteinn

Gufunes

Höfn Glacier Museum

Húsavík Whale Museum

The Icelandic Museum of Rock 'n' Roll

Icelandic Phallological Museum

ICGV Óðinn

Museum of Icelandic Sorcery and Witchcraft

National Gallery of Iceland

National Museum of Iceland

Reykjavík 871±2

Reykjavik Art Museum

Reykjavík Municipal Archives

Skóbúðin - museum of everyday life

Technical Museum of East Iceland

The Transportation Museum at Ystafell

The Árnesinga Folk Museum

The Herring Era Museum

Vikin Maritime Museum

The Arctic Fox Center

The Exploration Museum

Þjóðveldisbærinn Stöng

Viking World museum

Íslendingur

Volcano House

Westfjords Heritage Museum

List of types of fur

This list of types of fur describes the characteristics of types of fur used in fur clothing.

Operation Arctic Fox

Operation Arctic Fox (German: Unternehmen Polarfuchs; Finnish: operaatio Napakettu; Russian: Кандалакшская операция) was the codename given to a World War II campaign by German and Finnish forces against Soviet Northern Front defenses at Salla, Finland in July 1941. The operation was part of the larger Operation Silver Fox (Silberfuchs; Hopeakettu) which aimed to capture the vital port of Murmansk. Arctic Fox was conducted in parallel to Operation Platinum Fox (Platinfuchs; Platinakettu) in the far north of Lappland. The principal goal of Operation Arctic Fox was to capture the town of Salla and then to advance in the direction of Kandalaksha (Finnish: Kantalahti) to block the railway route to Murmansk.

As a joint operation by German and Finnish forces, it combined experienced Finnish arctic troops with relatively unsuitable German forces from Norway. They managed to capture Salla after fierce fighting, but the German troops were unable to overcome the old, pre-war Soviet border fortifications further east. The Finnish units were able to make better progress, and came to within 30 km (19 mi) of the Murmansk railway. Strong Soviet reinforcements prevented any further advance. Because of the escalating situation further south in Central Russia, the Germans were unwilling to assign more units to this theatre, calling an end to their offensive. While the Finns were reluctant to continue the attack on their own due to diplomatic pressure from the United States. Arctic Fox ended in November 1941, when both sides dug in at their current positions.

Operation Silver Fox

Operation Silver Fox (German: Silberfuchs; Finnish: Hopeakettu) from 29 June to 17 November 1941, was a German–Finnish military operation during World War II. The objective of the offensive was to cut off and capture the key Soviet Port of Murmansk through attacks from Finnish and Norwegian territory.

The operation had three stages, in Operation Reindeer (Rentier) German forces advanced from Norway to secure the area around Petsamo and its nickel mines. Operation Platinum Fox (Platinfuchs; Platinakettu) was an attack from the north by Mountain Corps Norway as XXXVI Mountain Corps and units from the Finnish III Corps, attacked from the south in Operation Arctic Fox (Polarfuchs; Napakettu) to cut off and capture Murmansk by a pincer movement. The German–Finnish forces took some ground but Murmansk was not cut off or captured and operated throughout the war.

Picken's Hole

Picken's Hole is a small cave on the southern side of Crook Peak in the Mendip Hills in the English county of Somerset. It has been designated as a scheduled monument. It has sometimes been confused with a nearby cave called Scragg's Hole, including by the Somerset Historic Environment Record.The cave is 8 metres (26 ft) below the plateau and 27 metres (89 ft) above the valley floor. It is named after M. J. Picken who found teeth in earth thrown out of their sets in the area by badgers.A number of Middle Palaeolithic artefacts, and two Neolithic teeth dated to about 4,800 years bp, were recovered from the cave. Faunal deposits of spotted hyena, lion, Arctic fox, mammoth, woolly rhinoceros, horse, reindeer, suslik and northern vole (Microtus oeconomus) from approximately 35,000 BP have also been recovered.

Promise Island

Promise Island (Inuktitut: Nannuyuma; meaning: "polar bear") is located near the western shore of Hudson Bay. It is barely a square kilometer in area and rises 300 ft (91 m) in elevation on its northern side. It is located about 9 km (5.6 mi) from the community of Chesterfield Inlet, Nunavut, Canada, and is part of a loose chain of small islands running along the coast, including the Wag Islands and Pitsiulartok (Fairway Island).

The island is home to a wide range of wildlife, including the Arctic fox (alopex lagopus innuitus), the harbor seal (phoca hispida), the polar bear, the brown lemming (lemmus t. trimucronatus), the barren-ground caribou (rangifer arcticus), and the red phalarope.

Reisa National Park

Reisa National Park (Norwegian: Reisa nasjonalpark) is a national park in Nordreisa Municipality in Troms county, Norway that was established by royal decree on 28 November 1986. The park has much wildlife. The rough-legged buzzard is the most common bird of prey, but hikers may also spot golden eagle, kestrels, and gyrfalcon. Wolverines and lynx live in the park and surrounding mountains. The Sámi name for part of the gorge, Njállaávzi, means Arctic fox gorge, suggesting that the Arctic fox must have lived there a long time. The largest Norwegian predator, the brown bear, is occasionally seen in the park.The Reisa river has cut a valley and a canyon (north of Imo) in the mountain plateau, producing the long fertile valley called Reisadalen. Waterfalls cascade into the valleys and gorges. The waterfall Mollisfossen is one of the more spectacular falls at 269 metres (883 ft) in height.The valley and adjacent mountains have been valuable for hunting, animal trapping, and fishing for centuries. Snares are sometimes still set to catch ptarmigan and willow grouse in the traditional manner. Scots pine were used for timber and to produce tar. Nearly every farm in the valley earned extra income making tar, and production continued far into the 20th century. The remains of many tar kilns can still be found. The park and surrounding areas provided spring, summer, and autumn grazing for semi-domesticated reindeer. In winter, the reindeer in this region graze in the Kautokeino district in nearby Finnmark county; in summer, they are on the coast in the northwest.It is adjacent to Käsivarsi Wilderness Area in Finland.

Siberian brown lemming

The Siberian brown lemming (Lemmus sibiricus) is a species of rodents in the family Cricetidae found in the Russian Federation. It does not hibernate during winter; it lives in burrows. It is prey to several animals, including the snowy owl and the Arctic fox. The lemmings are known for their high-amplitude, large-scale fluctuations of population sizes.

Snow camouflage

Snow camouflage is the use of a coloration or pattern for effective camouflage in winter, often combined with a different summer camouflage. Summer patterns are typically disruptively patterned combinations of shades of browns and greys, up to black, while winter patterns are dominated by white to match snowy landscapes.

Among animals, variable snow camouflage is a type of seasonal polyphenism with a distinct winter plumage or pelage. It is found in birds such as the rock ptarmigan, lagomorphs such as the Arctic hare, mustelids such as the stoat, and one canid, the Arctic fox. Since these have evolved separately, the similar appearance is due to convergent evolution. This was used as early evidence for natural selection. Some high Arctic species like the snowy owl and polar bear however remain white all year round.

In military usage, soldiers often either exchange their disruptively-patterned summer uniforms for thicker snow camouflage uniforms printed with mainly-white versions of camouflage patterns in winter, or they wear white overalls over their uniforms. Some armies have made use of reversible uniforms, printed in different seasonal patterns on their two sides. Vehicles and guns are often simply repainted in white. Occasionally, aircraft too are repainted in snow camouflage patterns.

The Arctic Fox Center

The Arctic Fox Center (Icelandic: Melrakkasetur) is a research center with an enclosed exhibition and café in the municipality Súðavík in the Westfjords in Iceland. It focuses on the Arctic fox (Vulpus lagopus) which is the only native terrestrial mammal in Iceland. The center was founded in 2007 by locals who are interested in the Arctic fox. It has a strong emphasis on ecotourism. The center is a non-profit-partner of 1% for the planet and a member of The Wild North.

Vulpes

Vulpes is a genus of the Canidae. The members of this genus are colloquially referred to as true foxes, meaning they form a proper clade. The word "fox" occurs on the common names of species. True foxes are distinguished from members of the genus Canis, such as dogs, wolves, coyotes, and jackals, by their smaller size (5–11 kg) and flatter skulls. They have black, triangular markings between their eyes and noses, and the tips of their tails are often a different color from the rest of their pelts. The typical lifespan for this genus is between two and four years, but can reach up to a decade.For animals commonly known as "foxes", but which are not true foxes, see Fox#Classification.

Vulpes qiuzhudingi

The ancestral Arctic fox Vulpes qiuzhudingi is an extinct species of fox found in the Himalayas. It was primarily carnivorous. The fossils, dating from between 5.08 and 3.60 million years ago, were found in the Zanda Basin and Kunlun Mountains of Tibet. It was named after Qiu Zhuding, a paleontologist from the Chinese Academy of Sciences. The species is believed to be the ancestor of Vulpes lagopus, the modern Arctic fox, which would support the "Out of Tibet" theory: namely, that a number of current arctic species trace their ancestry to species originally from the Tibetan Plateau.

Wretton SSSI

Wretton SSSI is a 20.6-hectare (51-acre) geological Site of Special Scientific Interest north-east of Downham Market in Norfolk. It is a Geological Conservation Review site.This site exposes layer across the transition between the warm Ipswichian and the colder Devensian around 115,000 years ago. It has the richest assemblage of early Devensian vertebrate fossils in Britain, including arctic fox, bison and woolly rhinoceros.A footpath runs along the boundary of part of the site.

Extant Carnivora species

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