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Fifty long-distance swims were recorded; the longest at 354 kilometres (220 mi), with an average of 155 kilometres (96 mi). [124], Female polar bears have been known to adopt other cubs. Only with the passage of the treaty did they begin to recover. A cub is about the size of a stick of butter when it is born. [195], Many chemicals, such as PCBs and DDT, have been internationally banned due to the recognition of their harm on the environment. They eat the ringed seal as well as the bearded seal and other pinnipeds. [22] Further, some clades of brown bear, as assessed by their mtDNA, were thought to be more closely related to polar bears than to other brown bears,[24] meaning that the brown bear might not be considered a species under some species concepts, but paraphyletic. [148][149] Polar bear remains have been found at hunting sites dating to 2,500 to 3,000 years ago[151] and 1,500-year-old cave paintings of polar bears have been found in the Chukchi Peninsula. But under their fur, polar bears have black skin—the better to soak in the sun's warming rays. Young polar bears testing their strength. Black bear fur is usually a uniform color except for a brown muzzle and light markings that sometimes appear on their chests. Among young males in particular, play-fighting may be a means of practicing for serious competition during mating seasons later in life. But climate change is making it harder for polar bears to hunt. Most people are familiar with polar bears from visiting zoos or seeing the bear depicted in the media, but there are many misconceptions about this fascinating animal. [3][2] He chose the scientific name Ursus maritimus, the Latin for 'maritime bear',[14] due to the animal's native habitat. They were also diving to feed on blue mussels and other underwater food sources like the green sea urchin. [32] This distinction has since been invalidated. Longevity in the wild is 25 to 30 years, but in captivity several polar bears have lived to more than 35 years old. Females first reproduce at four to eight years of age and breed every two to four years thereafter. [17] In Quebec, the polar bear is referred to as ours blanc ("white bear") or ours polaire ("polar bear"). Given the change in climate, with ice breaking up in areas such as the Hudson Bay earlier than it used to, polar bears are exploiting food resources such as snow geese and eggs, and plants such as lyme grass in increased quantities. [67], The white coat usually yellows with age. [133] The oldest wild bears on record died at age 32, whereas the oldest captive was a female who died in 1991, age 43. [148] The fur was used in particular to make trousers and, by the Nenets, to make galoshes-like outer footwear called tobok; the meat is edible, despite some risk of trichinosis; the fat was used in food and as a fuel for lighting homes, alongside seal and whale blubber; sinews were used as thread for sewing clothes; the gallbladder and sometimes heart were dried and powdered for medicinal purposes; the large canine teeth were highly valued as talismans. [72] With its body fat providing buoyancy, the bear swims in a dog paddle fashion using its large forepaws for propulsion. (2011). [23] Polar bears are thought to have diverged from a population of brown bears that became isolated during a period of glaciation in the Pleistocene[4] from the eastern part of Siberia (from Kamchatka and the Kolym Peninsula). ", "Determinants of Home Range Size for Polar Bears (, "Polar Bear Ursus maritimus – APPEARANCE/ MORPHOLOGY: TAIL", "Fractures of the radius and ulna secondary to possible vitamin 'D' deficiency in captive polar bears (, "Population genomics reveal recent speciation and rapid evolutionary adaptation in polar bears", 10.1644/1545-1542(2005)86[895:SDOPB]2.0.CO;2. For the We Bare Bears character, see, Species of bear native largely to the Arctic Circle, Coat of arms of the Greenlandic Self-Rule government (, Conservation status, threats, and controversies. [9] Although most polar bears are born on land, they spend most of their time on the sea ice. [190], In Alaska, the effects of sea ice shrinkage have contributed to higher mortality rates in polar bear cubs, and have led to changes in the denning locations of pregnant females. Polar bears prefer ice that is subject to periodic fracturing by wind and sea currents, because these fractures offer seals access to both air and water. [109] This study illustrates the polar bear's dietary flexibility but it does not represent its life history elsewhere. [52] Adult male polar bears weigh 350–700 kg (770–1,500 lb) and measure 2.4–3 metres (7 ft 10 in–9 ft 10 in) in total length. It is the largest extant bear species, as well as the largest extant land carnivore. A polar bear may also hunt by swimming beneath the ice. Babies are born blind. [2] Because polar bears rely partly on their fur for insulation and soiling of the fur by oil reduces its insulative value, oil spills put bears at risk of dying from hypothermia. Ursus polaris Although polar bear meat is consumed by aboriginals, the liver is inedible and often poisonous because of its high vitamin A content. It was believed that the "little nephew" (the brown bear) would not dare to attack a man wearing the tooth of its powerful "big uncle", the polar bear. It is born hairless, with its eyes closed. Along with a voracious appetite it has a reputation for unmatched ferocity and apparently fears nothing. 900 bears a year were harvested in the 1920s and after World War II, there were as many as 400–500 harvested annually. Please refer to the appropriate style manual or other sources if you have any questions. 2) These are seriously big bears, gang. [73], Brown bears tend to dominate polar bears in disputes over carcasses,[136] and dead polar bear cubs have been found in brown bear dens. [37] Canada has allowed sport hunters accompanied by local guides and dog-sled teams since 1970,[164] but the practice was not common until the 1980s. Ringed seals are born weighing 5.4 kg (12 lb) and grown to an estimated average weight of only 60 kg (130 lb). Killing of polar bears decreased somewhat 25–30 years before the treaty. [194] Halocarbons (also known as organohalogens) are known to be toxic to other animals, because they mimic hormone chemistry, and biomarkers such as immunoglobulin G and retinol suggest similar effects on polar bears. Depending on the timing of ice-floe breakup in the fall, she may have fasted for up to eight months. "[75] Cubs are especially playful as well. [95][100] Polar bears may attempt to consume almost anything they can find, including hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil. Strong, sharp claws are also important for gaining traction, for digging through ice, and for killing prey. [121] Her body temperature does not decrease during this period as it would for a typical mammal in hibernation. The polar bear (Ursus maritimus) is the largest terrestrial carnivore in the world, rivaled in size only by the Kodiak bear.Polar bears play an important role in the life and culture of the Arctic Circle. …strong swimmers, most notably the polar bear. It is also called white bear or northern bear.It has black skin under the white fur. They still manage to consume some seals, but they are food-deprived in summer as only marine mammal carcasses are an important alternative without sea ice, especially carcasses of the beluga whale. This hibernation-like state does not consist of continuous sleeping; however, the bear's heart rate slows from 46 to 27 beats per minute. Our editors will review what you’ve submitted and determine whether to revise the article. Ursus marinus Other concerns for polar bears include lethal response to human-polar bear conflict, toxic pollution in the environment, and direct impacts from industrial development, such as disturbance of maternal dens or contact with an oil spill, and potential overhunting of some subpopulations. "The influence of climate variability on polar bear (, "Diet composition of polar bears in Svalbard and the western Barents Sea", https://animaldiversity.org/accounts/Ursus_maritimus/, "Interactions between polar bears and overwintering walruses in the Central Canadian High Arctic", "Polar bear metabolism cannot cope with ice loss", "Comments on 'Carnivorous walrus and some Arctic zoonoses, "Hudson Bay Post — Goodbye Churchil [sic] Dump", "What to eat now? [135] Several animal species, particularly Arctic foxes (Vulpes lagopus) and glaucous gulls (Larus hyperboreus), routinely scavenge polar bear kills. You will find that the natural habitat for the Polar Bear is in the very cold areas of the world. 475–485 in Wild furbearer management and conservation in North America (M. Novak, J. [131], The polar bear is the apex predator within its range, and is a keystone species for the Arctic. Michio Hoshino, a Japanese wildlife photographer, was once pursued briefly by a hungry male polar bear in northern Alaska. They are strong and can swim very well. [79] However, due to the very small human population around the Arctic, such attacks are rare. In 2005, the government of Nunavut increased the quota from 400 to 518 bears,[166] despite protests from the IUCN Polar Bear Specialist Group. On 15 May 2008, the United States Department of the Interior listed the polar bear as a threatened species under the Endangered Species Act, citing the melting of Arctic sea ice as the primary threat to the polar bear. [181] As of 2015, the International Union for Conservation of Nature (IUCN) reports that the global population of polar bears is 22,000 to 31,000, and the current population trend is unknown. [85][86] The pair wrestled harmlessly together each afternoon for 10 days in a row for no apparent reason, although the bear may have been trying to demonstrate its friendliness in the hope of sharing the kennel's food. Unlike brown and black bears, polar bears are capable of fasting for up to several months during late summer and early fall, when they cannot hunt for seals because the sea is unfrozen. Hunters commonly used teams of dogs to distract the bear, allowing the hunter to spear the bear or shoot it with arrows at closer range. Polar bears feature prominently in East (North Child in the UK) by Edith Pattou,[221] The Bear by Raymond Briggs (adapted into an animated short in 1998),[222] and Chris d'Lacey's The Fire Within series. The skin is not white; it is black. Polar bears exposed to oil spill conditions have been observed to lick the oil from their fur, leading to fatal kidney failure. When the seal exhales, the bear smells its breath, reaches into the hole with a forepaw, and drags it out onto the ice. An oil spill in the Arctic would most likely concentrate in the areas where polar bears and their prey are also concentrated, such as sea ice leads. [78] Polar bears sometimes swim underwater to catch fish like the Arctic charr or the fourhorn sculpin. [200] However, most polar bear biologists think that polar bears will be unable to completely offset the loss of calorie-rich seal blubber with terrestrial foods, and that they will be outcompeted by brown bears in this terrestrial niche, ultimately leading to a population decline. [151], In Russia, polar bear furs were already being commercially traded in the 14th century, though it was of low value compared to Arctic fox or even reindeer fur. 1) Polar bears are found in the frozen wilds of the Arctic, in Canada, Alaska (US), Greenland, Russia and Norway. Polar Bear teaches the value of remaining inconspicuous until the moment arrives for your unveiling. [90], The polar bear's most common hunting method is called still-hunting:[91] the bear uses its excellent sense of smell to locate a seal breathing hole, and crouches nearby in silence for a seal to appear. According to the IUCN Red List of Threatened Species, the category of vulnerable, as distinct from the category of endangered, means that polar bears have a slightly lower risk of extinction than if they were endangered. It banned hunting (except by indigenous subsistence hunters), banned importing of polar bear parts (except polar bear pelts taken legally in Canada), and banned the harassment of polar bears. [139][140] The remains of polar bears have found in the stomachs of large Greenland sharks (Somniosus microcephalus), although it certainly cannot be ruled out that the bears were merely scavenged by this slow-moving, unusual shark. The bear was able to reach the truck and tore one of the doors off the truck before Hoshino was able to drive off. [178] Since 1994, hundreds of sport-hunted polar bear trophies have been imported into the U.S.[179] In 2015, the U.S. Britannica now has a site just for parents! Several such sites have been preserved on the Yamal Peninsula. Polar bear news, and video clips from BBC programmes past and present. [167] In two areas where harvest levels have been increased based on increased sightings, science-based studies have indicated declining populations, and a third area is considered data-deficient. Facts about these endangered animals, their life in the North Pole, and arctic circle, and the food sources they hunt and scavenge for. Increased human-bear interactions, including fatal attacks on humans, are likely to increase as the sea ice shrinks and hungry bears try to find food on land. [187] The Western Hudson Bay subpopulation, in a southern part of the range, also happens to be one of the best-studied polar bear subpopulations. Let us know if you have suggestions to improve this article (requires login). [60] Two genes that are known to influence melanin production, LYST and AIM1, are both mutated in polar bears, possibly leading to the absence on this pigment in their fur. [54] Adult females are roughly half the size of males and normally weigh 150–250 kg (330–550 lb), measuring 1.8–2.4 metres (5 ft 11 in–7 ft 10 in) in length. The bear may lie in wait for several hours. This article was most recently revised and updated by, https://www.britannica.com/animal/polar-bear, SeaWorld Parks and Entertainment - Polar Bear, The National Wildlife Federation - Polar Bear, polar bear - Children's Encyclopedia (Ages 8-11), polar bear - Student Encyclopedia (Ages 11 and up), International Union for Conservation of Nature. Why Didn't the Wild Polar Bear eat the Husky? [48] In the Chukchi and Beaufort seas, polar bears retreat each summer to the ice further north that remains frozen year-round. The sea ice provides a platform from which polar bears can hunt. [2], There are several reasons for the apparent discordance between past and projected population trends: estimates from the 1950s and 1960s were based on stories from explorers and hunters rather than on scientific surveys. Polar bears appear to be less affected by infectious diseases and parasites than most terrestrial mammals. [106][107], Although seal predation is the primary and an indispensable way of life for most polar bears, when alternatives are present they are quite flexible. While the algae is harmless to the bears, it is often a worry to the zoos housing them, and affected animals are sometimes washed in a salt solution, or mild. The mitochondrial DNA (mtDNA) of the polar bear diverged from the brown bear, Ursus arctos, roughly 150,000 years ago. Polar bear, great white northern bear found throughout the Arctic region. [118] A male may follow the tracks of a breeding female for 100 km (60 mi) or more, and after finding her engage in intense fighting with other males over mating rights, fights that often result in scars and broken teeth. [89], With the exception of pregnant females, polar bears are active year-round, although they have a vestigial hibernation induction trigger in their blood. The male, which is much larger than the female, weighs 410 to 720 kg (900 to 1,600 pounds). [90] However, in the short term, some polar bear populations in historically colder regions of the Arctic may temporarily benefit from a milder climate, as multiyear ice that is too thick for seals to create breathing holes is replaced by thinner annual ice. In 1927, poisoning was outlawed while in 1939, certain denning sights were declared off limits. [73], The relationship between ringed seals and polar bears is so close that the abundance of ringed seals in some areas appears to regulate the density of polar bears, while polar bear predation in turn regulates density and reproductive success of ringed seals. Whereas brown bears often maul a person and then leave, polar bear attacks are more likely to be predatory and are almost always fatal. Breeding Season: Pups born from November to February in a den in the depths of winter. [78] Many attacks by brown bears are the result of surprising the animal, which is not the case with the polar bear. [31], When the polar bear was originally documented, two subspecies were identified: the American polar bear (Ursus maritimus maritimus) by Constantine J. Phipps in 1774, and the Siberian polar bear (Ursus maritimus marinus) by Peter Simon Pallas in 1776. [166], The territory of Nunavut accounts for the location 80% of annual kills in Canada. [26] A comparison of the nuclear genome of polar bears with that of brown bears revealed a different pattern, the two forming genetically distinct clades that diverged approximately 603,000 years ago,[27] although the latest research is based on analysis of the complete genomes (rather than just the mitochondria or partial nuclear genomes) of polar and brown bears, and establishes the divergence of polar and brown bears at 400,000 years ago. Polar bears are stocky, with a long neck, relatively small head, short, rounded ears, and a short tail. [31] The claws are deeply scooped on the underside to assist in digging in the ice of the natural habitat. The family remains in the den until mid-February to mid-April, with the mother maintaining her fast while nursing her cubs on a fat-rich milk. For the polar bears that currently den on multi-year ice, increased ice mobility may result in longer distances for mothers and young cubs to walk when they return to seal-hunting areas in the spring. [169] In 2010, the 2005 increase was partially reversed. [209][210] Many Inuit believe the polar bear population is increasing, and restrictions on commercial sport-hunting are likely to lead to a loss of income to their communities. [213] Vehicle licence plates in the Northwest Territories in Canada are in the shape of a polar bear, as was the case in Nunavut until 2012; these now display polar bear artwork instead. Pound for pound few other animals can match the wolverine for strength or […] [141][142] A rather unlikely killer of a grown polar bear has reportedly included a wolverine (Gulo gulo), anecedotely reported to have suffocated a bear in a zoo with a bite to the throat during a conflict. [43], In August 2011, Environment Canada published a national polar bear conservation strategy. [197][198] The bears could disappear from Europe, Asia, and Alaska, and be depleted from the Canadian Arctic Archipelago and areas off the northern Greenland coast. Polar bears rarely live beyond 25 years. They will even attack adult walruses when their diving holes have frozen over or intercept them before they can get back to the diving hole in the ice. Indeed, it has been suggested that Arctic peoples' skills in seal hunting and igloo construction has been in part acquired from the polar bears themselves. Kolenosky G. B. [53] The polar bear is among the most sexually dimorphic of mammals, surpassed only by the pinnipeds such as elephant seals. Be some discrepancies of aggression when swimming, which remained and were eaten during the same time,! Their fur, leading to fatal kidney failure on Spitsbergen harvested 150 polar bears in. 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