Polar bear
Polar bear Temporal range: Pleistocene–recent[1]
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Female near Kaktovik, Barter Island, Alaska, United States | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Carnivora |
Family: | Ursidae |
Genus: | Ursus |
Species: | U. maritimus
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Binomial name | |
Ursus maritimus Phipps, 1774[4] | |
Polar bear range | |
Synonyms | |
Ursus eogroenlandicus |
The polar bear (Ursus maritimus) is a large
Polar bears are both terrestrial and pagophilic (ice-living) and are considered to be marine mammals due to their dependence on marine ecosystems. They prefer the annual sea ice but live on land when the ice melts in the summer. They are mostly carnivorous and specialized for preying on seals, particularly ringed seals. Such prey is typically taken by ambush; the bear may stalk its prey on the ice or in the water, but also will stay at a breathing hole or ice edge to wait for prey to swim by. The bear primarily feeds on the seal's energy-rich blubber. Other prey include walruses, beluga whales and some terrestrial animals. Polar bears are usually solitary but can be found in groups when on land. During the breeding season, male bears guard females and defend them from rivals. Mothers give birth to cubs in maternity dens during the winter. Young stay with their mother for up to two and a half years.
The polar bear is considered to be a vulnerable species by the International Union for Conservation of Nature (IUCN) with an estimated total population of 22,000 to 31,000 individuals. Its biggest threats are climate change, pollution and energy development. Climate change has caused a decline in sea ice, giving the polar bear less access to its favoured prey and increasing the risk of malnutrition and starvation. Less sea ice also means that the bears must spend more time on land, increasing conflicts with people. Polar bears have been hunted, both by native and non-native peoples, for their coats, meat and other items. They have been kept in captivity in zoos and circuses and are prevalent in art, folklore, religion and modern culture.
Naming
The polar bear was given its common name by Thomas Pennant in A Synopsis of Quadrupeds (1771). It was known as the "white bear" in Europe between the 13th and 18th centuries, as well as "ice bear", "sea bear" and "Greenland bear". The Norse referred to it as isbjørn 'ice bear' and hvitebjørn 'white bear'. The bear is called nanook by the Inuit. The Netsilik cultures additionally have different names for bears based on certain factors, such as sex and age: these include adult males (anguraq), single adult females (tattaq), gestating females (arnaluk), newborns (hagliaqtug), large adolescents (namiaq) and dormant bears (apitiliit).[5] The scientific name Ursus maritimus is Latin for 'sea bear'.[6][7]
Taxonomy
Different subspecies have been proposed including Ursus maritimus maritimus and U. m. marinus.[a][13] However these are not supported and the polar bear is considered to be monotypic.[14] One possible fossil subspecies, U. m. tyrannus, was posited in 1964 by Björn Kurtén, who reconstructed the subspecies from a single fragment of an ulna which was approximately 20 percent larger than expected for a polar bear.[12] However, re-evaluation in the 21st century has indicated that the fragment likely comes from a giant brown bear.[15][16]
Evolution
The polar bear is one of eight extant species in the bear family, Ursidae, and of six extant species in the subfamily Ursinae. A possible phylogeny of extant bear species is shown in a cladogram based on complete mitochondrial DNA sequences from Yu et al. (2007).[17] The polar bear and the brown bear form a close grouping, while the relationships of the other species are not very well resolved.[18]
Ursidae |
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A more recent phylogeny below is based on a 2017 genetic study. The study concludes that Ursine bears originated around 5 million years ago and show extensive hybridization of species in their lineage.[19]
Ursidae |
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Fossils of polar bears are uncommon.
More extensive genetic studies have refuted the idea that polar bears are directly descended from brown bears and found that the two species are separate
Studies in 2011 and 2012 concluded that
Analysis of the
Characteristics
The polar bear is the largest living species of bear and land carnivore, though some brown bear subspecies like the Kodiak bear can rival it in size.[31][32] Males are generally 200–250 cm (6.6–8.2 ft) long with a weight of 300–800 kg (660–1,760 lb). Females are smaller at 180–200 cm (5.9–6.6 ft) with a weight of 150–300 kg (330–660 lb).[10] Sexual dimorphism in the species is particularly high compared with most other mammals.[33] Male polar bears also have proportionally larger heads than females.[34] The weight of polar bears fluctuates during the year, as they can bulk up on fat and increase their mass by 50 percent.[31] A fattened, pregnant female can weigh as much as 500 kg (1,100 lb).[35] Adults may stand 130–160 cm (4.3–5.2 ft) tall at the shoulder. The tail is 76–126 mm (3.0–5.0 in) long.[10] The largest polar bear on record, reportedly weighing 1,002 kg (2,209 lb), was a male shot at Kotzebue Sound in northwestern Alaska in 1960.[36]
Compared with the brown bear, this species has a more slender build, with a narrower, flatter and smaller skull, a longer neck, and a lower shoulder hump.
The coat consists of dense
The eyes of a polar bear are close to the top of the head, which may allow them to stay out of the water when the animal is swimming at the surface. They are relatively small, which may be an adaption against blowing snow and
Distribution and habitat
Polar bears inhabit the
Polar bears have been divided into at least 18 subpopulations labelled East Greenland (ES), Barents Sea (BS), Kara Sea (KS), Laptev Sea (LVS), Chukchi Sea (CS), northern and southern Beaufort Sea (SBS and NBS), Viscount Melville (VM), M'Clintock Channel (MC), Gulf of Boothia (GB), Lancaster Sound (LS), Norwegian Bay (NB), Kane Basin (KB), Baffin Bay (BB), Davis Strait (DS), Foxe Basin (FB) and the western and southern Hudson Bay (WHB and SHB) populations.[62][56] Bears in and around the Queen Elizabeth Islands have been proposed as a subpopulation but this is not universally accepted.[56] A 2022 study has suggested that the bears in southeast Greenland should be considered a different subpopulation based on their geographic isolation and genetics.[63] Polar bear populations can also be divided into four gene clusters: Southern Canadian, Canadian Archipelago, Western Basin (northwestern Canada west to the Russian Far East) and Eastern Basin (Greenland east to Siberia).[62]
The polar bear is dependent enough on the ocean to be considered a
Behaviour and ecology
Polar bears may travel areas as small as 3,500 km2 (1,400 sq mi) to as large as 38,000 km2 (15,000 sq mi) in a year, while drifting ice allows them to move further.
Most polar bears are active year-round. Hibernation occurs only among pregnant females.[80] Non-hibernating bears typically have a normal 24-hour cycle even during days of all darkness or all sunlight, though cycles less than a day are more common during the former.[81] The species is generally diurnal, being most active early in the day.[82] Polar bears sleep close to eight hours a day on average.[83] They will sleep in various positions, including curled up, sitting up, lying on one side, on the back with limbs spread, or on the belly with the rump elevated.[42][76] On sea ice, polar bears snooze at pressure ridges where they dig on the sheltered side and lie down. After a snowstorm, a bear may rest under the snow for hours or days. On land, the bears may dig a resting spot on gravel or sand beaches.[84] They will also sleep on rocky outcrops.[85] In mountainous areas on the coast, mothers and subadults will sleep on slopes where they can better spot another bear coming.[83] Adult males are less at risk from other bears and can sleep nearly anywhere.[85]
Social life
Polar bears are typically solitary, aside from mothers with cubs and mating pairs.[86] On land, they are found closer together and gather around food resources. Adult males, in particular, are more tolerant of each other in land environments and outside the breeding season.[87][88] They have been recorded forming stable "alliances", travelling, resting and playing together. A dominance hierarchy exists among polar bears with the largest mature males ranking at the top. Adult females outrank subadults and adolescents and younger males outrank females of the same age. In addition, cubs with their mothers outrank those on their own.[89] Females with dependent offspring tend to stay away from males,[88] but are sometimes associated with other female–offspring units, creating "composite families".[89]
Polar bears are generally quiet but can produce various sounds.[90] Chuffing, a soft pulsing call, is made by mother bears presumably to keep in contact with their young.[91] During the breeding season, adult males will chuff at potential mates.[92] Unlike other animals where chuffing is passed through the nostrils, in polar bears it is emitted through a partially open mouth.[91] Cubs will cry for attention and produce humming noises while nursing.[93] Teeth chops, jaw pops, blows, huffs, moans, growls and roars are heard in more hostile encounters.[92] A polar bear visually communicates with its eyes, ears, nose and lips.[89] Chemical communication can also be important: bears secrete their scent from their foot pads into their tracks, allowing individuals to keep track of one another.[94]
Diet and hunting
The polar bear is a hypercarnivore,[95] and the most carnivorous species of bear.[37] It is an apex predator of the Arctic,[96] preying on ice-living seals and consuming their energy-rich blubber.[97] The most commonly taken species is the ringed seal, but they also prey on bearded seals and harp seals.[10] Ringed seals are ideal prey as they are abundant and small enough to be overpowered by even small bears.[98] Bearded seal adults are larger and are more likely to break free from an attacking bear, hence adult male bears are more successful in hunting them. Less common prey are hooded seals, spotted seals, ribbon seals and the more temperate-living harbour seals.[99] Polar bears, mostly adult males, will occasionally hunt walruses, both on land and ice, though they mainly target the young, as adults are too large and formidable, with their thick skin and long tusks.[100]
Besides seals, bears will prey on cetacean species such as beluga whales and narwhals, as well as reindeer, birds and their eggs, fish and marine invertebrates.[101] They rarely eat plant material as their digestive system is too specialized for animal matter,[102] though they have been recorded eating berries, moss, grass and seaweed.[103] In their southern range, especially near Hudson Bay and James Bay, polar bears endure all summer without sea ice to hunt from and must subsist more on terrestrial foods.[104] Fat reserves allow polar bears to survive for months without eating.[105] Cannibalism is known to occur in the species.[106]
Polar bears hunt their prey in several different ways. When a bear spots a seal hauling out on the sea ice, it slowly stalks it with the head and neck lowered, possibly to make its dark nose and eyes less noticeable. As it gets closer, the bear crouches more and eventually charges at a high speed, attempting to catch the seal before it can escape into its ice hole. Some stalking bears need to move through water; traversing through water cavities in the ice when approaching the seal or swimming towards a seal on an ice floe. The polar bear can stay underwater with its nose exposed. When it gets close enough, the animal lunges from the water to attack.[107]
During a limited time in spring, polar bears will search for ringed seal pups in their birth lairs underneath the ice. Once a bear catches the scent of a hiding pup and pinpoints its location, it approaches the den quietly to not alert it. It uses its front feet to smash through the ice and then pokes its head in to catch the pup before it can escape. A ringed seal's lair can be more than 1 m (3.3 ft) below the surface of the ice and thus more massive bears are better equipped for breaking in. Some bears may simply stay still near a breathing hole or other spot near the water and
Bears hunt walrus groups by provoking them into stampeding and then look for young that have been crushed or separated from their mothers during the turmoil.
Arctic foxes routinely follow polar bears and scavenge scraps from their kills. The bears usually tolerate them but will charge a fox that gets too close when they are feeding. Polar bears themselves will scavenge. Subadult bears will eat remains left behind by others. Females with cubs often abandon a carcass when they see an adult male approaching, though are less likely to if they have not eaten in a long time.[115] Whale carcasses are a valuable food source, particularly on land and after the sea ice melts, and attract several bears.[87] In one area in northeastern Alaska, polar bears have been recorded competing with grizzly bears for whale carcasses. Despite their smaller size, grizzlies are more aggressive and polar bears are likely to yield to them in confrontations.[116] Polar bears will also scavenge at garbage dumps during ice-free periods.[117]
Reproduction and development
Polar bear mating takes place on the sea ice and during spring, mostly between March and May.
Upon finding a female, a male will try to isolate and guard her. Courtship can be somewhat aggressive, and a male will pursue a female if she tries to run away. It can take days for the male to mate with the female which induces ovulation. After their first copulation, the couple bond. Undisturbed polar bear pairings typically last around two weeks during which they will sleep together and mate multiple times.[122] Competition for mates can be intense and this has led to sexual selection for bigger males. Polar bear males often have scars from fighting.[118][119] A male and female that have already bonded will flee together when another male arrives.[123] A female mates with multiple males in a season and a single litter can have more than one father.[121]
When the mating season ends, the female will build up more fat reserves to sustain both herself and her young. Sometime between August and October, the female constructs and enters a
Mother polar bears typically give birth to two cubs per litter. As with other bear species, newborn polar bears are tiny and altricial.[129] The newborns have woolly hair and pink skin, with a weight of around 600 g (21 oz).[10][31] Their eyes remain closed for a month.[130] The mother's fatty milk fuels their growth, and the cubs are kept warm both by the mother's body heat and the den. The mother emerges from the den between late February and early April, and her cubs are well-developed and capable of walking with her.[131] At this time they weigh 10–15 kilograms (22–33 lb).[10] A polar bear family stays near the den for roughly two weeks; during this time the cubs will move and play around while the mother mostly rests. They eventually head out on the sea ice.[132]
Cubs under a year old stay close to their mother. When she hunts, they stay still and watch until she calls them back.
Mortality
Polar bears can live up to 30 years.
Subadult bears, who are independent but not quite mature, have a particularly rough time as they are not as successful hunters as adults. Even when they do succeed, their kill will likely be stolen by a larger bear. Hence subadults have to scavenge and are often underweight and at risk of starvation. At adulthood, polar bears have a high survival rate, though adult males suffer injuries from fights over mates.
Conservation status
In 2015, the IUCN Red List categorized the polar bear as vulnerable due to a "decline in area of occupancy, extent of occurrence and/or quality of habitat". It estimated the total population to be between 22,000 and 31,000, and the current population trend is unknown. Threats to polar bear populations include climate change, pollution and energy development.[2]
In 2021, the IUCN/SSC Polar Bear Specialist Group labelled four subpopulations (Barents and Chukchi Sea, Foxe Basin and Gulf of Boothia) as "likely stable", two (Kane Basin and M'Clintock Channel) as "likely increased" and three (Southern Beaufort Sea, Southern and Western Hudson Bay) as "likely decreased" over specific periods between the 1980s and 2010s. The remaining ten did not have enough data.[56] A 2008 study predicted two-thirds of the world's polar bears may disappear by 2050, based on the reduction of sea ice, and only one population would likely survive in 50 years.[145] A 2016 study projected a likely decline in polar bear numbers of more than 30 percent over three generations. The study concluded that declines of more than 50 percent are much less likely.[146] A 2012 review suggested that polar bears may become regionally extinct in southern areas by 2050 if trends continue, leaving the Canadian Archipelago and northern Greenland as strongholds.[147]
The key danger from climate change is malnutrition or starvation due to habitat loss. Polar bears hunt seals on the sea ice, and rising temperatures cause the ice to melt earlier in the year, driving the bears to shore before they have built sufficient fat reserves to survive the period of scarce food in the late summer and early fall. Thinner sea ice tends to break more easily, which makes it more difficult for polar bears to access seals. Insufficient nourishment leads to lower reproductive rates in adult females and lower survival rates in cubs and juvenile bears. Lack of access to seals also causes bears to find food on land which increases the risk of conflict with humans.[61][147] A 2024 study concluded that greater consumption of terrestrial foods during the longer warm periods are unlikely to provide enough nourishment, increasing the risk of starvation during ice-free periods. Subadult bears would be particularly vulnerable.[148]
Reduction in sea ice cover also forces bears to swim longer distances, which further depletes their energy stores and occasionally leads to drowning. Increased ice mobility may result in less stable sites for dens or longer distances for mothers travelling to and from dens on land. Thawing of
Oil and gas development also affects polar bear habitat. The Chukchi Sea Planning Area of northwestern Alaska, which has had many drilling leases, was found to be an important site for non-denning female bears.
Polar bears receive some legal protection in all the countries they inhabit. The species has been labelled as threatened under the US Endangered Species Act since 2008,[153] while the Committee on the Status of Endangered Wildlife in Canada listed it as of 'Special concern' since 1991.[154] In 1973, the Agreement on the Conservation of Polar Bears was signed by all five nations with polar bear populations, Canada, Denmark (of which Greenland is an autonomous territory), Russia (then USSR), Norway and the US. This banned most harvesting of polar bears, allowed indigenous hunting using traditional methods, and promoted the preservation of bear habitat.[155] The Convention on International Trade in Endangered Species of Wild Fauna lists the species under Appendix II,[3] which allows regulated trade.[156]
Relationship with humans
Polar bears have coexisted and interacted with circumpolar peoples for millennia.[157] "White bears" are mentioned as commercial items in the Japanese book Nihon Shoki in the seventh century. It is not clear if these were polar bears or white-coloured brown bears.[158] During the Middle Ages, Europeans considered white bears to be a novelty and were more familiar with brown- and black-coloured bears.[159] The first known written account of the polar bear in its natural environment is found in the 13th-century anonymous Norwegian text Konungs skuggsjá, which mentions that "the white bear of Greenland wanders most of the time on the ice of the sea, hunting seals and whales and feeding on them" and says the bear is "as skillful a swimmer as any seal or whale".[160]
Over the next centuries, several European explorers would mention polar bears and describe their habits.
Exploitation
Polar bears were hunted as early as 8,000 years ago, as indicated by archaeological remains at Zhokhov Island in the East Siberian Sea. The oldest graphic depiction of a polar bear shows it being hunted by a man with three dogs. This rock art was among several petroglyphs found at Pegtymel in Siberia and dates from the fifth to eighth centuries. Before access to firearms, native people used lances, bows and arrows and hunted in groups accompanied by dogs. Though hunting typically took place on foot, some people killed swimming bears from boats with a harpoon. Polar bears were sometimes killed in their dens. Killing a polar bear was considered a rite of passage for boys in some cultures. Native people respected the animal and hunts were subject to strict rituals.[165] Bears were harvested for the fur, meat, fat, tendons, bones and teeth.[166][167] The fur was worn and slept on, while the bones and teeth were made into tools. For the Netsilik, the individual who finally killed the bear had the right to its fur while the meat was passed to all in the party. Some people kept the cubs of slain bears.[168]
Norsemen in Greenland traded polar bear furs in the Middle Ages.[169] Russia traded polar bear products as early as 1556, with Novaya Zemlya and Franz Josef Land being important commercial centres. Large-scale hunting of bears at Svalbard occurred since at least the 18th century, when no less than 150 bears were killed each year by Russian explorers. In the next century, more Norwegians were harvesting the bears on the island. From the 1870s to the 1970s, around 22,000 of the animals were hunted in total. Over 150,000 polar bears in total were either killed or captured in Russia and Svalbard, from the 18th to the 20th century. In the Canadian Arctic, bears were harvested by commercial whalers especially if they could not get enough whales. The Hudson's Bay Company is estimated to have sold 15,000 polar bear coats between the late 19th century and early 20th century.[170] In the mid-20th century, countries began to regulate polar bear harvesting, culminating in the 1973 agreement.[155]
Polar bear meat was commonly eaten as rations by explorers and sailors in the Arctic. Its taste and texture have been described both positively and negatively. Some have called it too coarse with a powerful smell, while others praised it as a "royal dish".[171] The liver was known for being too toxic to eat. This is due to the accumulation of vitamin A from their prey.[172] Polar bear fat was also used in lamps when other fuel was unavailable.[171] Polar bear rugs were almost ubiquitous on the floors of Norwegian churches by the 13th and 14th centuries. In more modern times, classical Hollywood actors would pose on bearskin rugs, notably Marilyn Monroe. Such images often had sexual connotations.[173]
Conflicts
When the sea ice melts, polar bears, particularly subadults, conflict with humans over resources on land.[174] They are attracted to the smell of human-made foods, particularly at garbage dumps and may be shot when they encroach on private property.[175] In Churchill, Manitoba, local authorities maintain a "polar bear jail" where nuisance bears are held until the sea ice freezes again.[176] Climate change has increased conflicts between the two species.[174] Over 50 polar bears swarmed a town in Novaya Zemlya in February 2019, leading local authorities to declare a state of emergency.[177]
From 1870 to 2014, there were an estimated 73 polar bear attacks on humans, which led to 20 deaths. The majority of attacks were by hungry males, typically subadults, while female attacks were usually in defence of the young. In comparison to brown and American black bears, attacks by polar bears were more often near and around where humans lived. This may be due to the bears getting desperate for food and thus more likely to seek out human settlements. As with the other two bear species, polar bears are unlikely to target more than two people at once. Though popularly thought of as the most dangerous bear, the polar bear is no more aggressive to humans than other species.[178]
Captivity
The polar bear was a particularly sought-after species for exotic animal collectors due to being relatively rare and remote living, and its reputation as a ferocious beast.[179] It is one of the few marine mammals that can reproduce well in captivity.[180] They were originally kept only by royals and elites. The Tower of London got a polar bear as early as 1252 under King Henry III. In 1609, James VI and I of Scotland, England and Ireland was given two polar bear cubs by the sailor Jonas Poole, who got them during a trip to Svalbard.[181] At the end of the 17th century, Frederick I of Prussia housed polar bears in menageries with other wild animals. He had their claws and canines removed to perform mock fights. Around 1726, Catherine I of Russia gifted two polar bears to Augustus II the Strong of Poland, who desired them for his animal collection.[182] Later, polar bears were displayed to the public in zoos and circuses.[183] In early 19th century, the species was exhibited at the Exeter Exchange in London, as well as menageries in Vienna and Paris. The first zoo in North America to exhibit a polar bear was the Philadelphia Zoo in 1859.[184]
Polar bear exhibits were innovated by
Polar bears have been trained to perform in circuses. Bears in general, being large, powerful, easy to train and human-like in form, were widespread in circuses, and the white coat of polar bears made them particularly attractive. Circuses helped change the polar bear's image from a fearsome monster to something more comical. Performing polar bears were used in 1888 by Circus Krone in Germany and later in 1904 by the Bostock and Wombwell Menagerie in England. Circus director Wilhelm Hagenbeck trained up to 75 polar bears to slide into a large tank through a chute. He began performing with them in 1908 and they had a particularly well-received show at the Hippodrome in London. Other circus tricks performed by polar bears involved tightropes, balls, roller skates and motorcycles. One of the most famous polar bear trainers in the second half of the twentieth century was the East German Ursula Böttcher, whose small stature contrasted with that of the large bears. Starting in the late 20th century, most polar bear acts were retired and the use of these bears for the circus is now prohibited in the US.[189]
Several captive polar bears gained celebrity status in the late 20th and early 21st century, notably
Cultural significance
Polar bears have prominent roles in
Nordic folklore and literature have also featured polar bears. In The Tale of Auðun of the West Fjords, written around 1275, a poor man named Auðun spends all his money on a polar bear in Greenland, but ends up wealthy after giving the bear to the king of Denmark.[197] In the 14th-century manuscript Hauksbók, a man named Odd kills and eats a polar bear that killed his father and brother. In the story of The Grimsey Man and the Bear, a mother bear nurses and rescues a farmer stuck on an ice floe and is repaid with sheep meat. 18th-century Icelandic writings mention the legend of a "polar bear king" known as the bjarndýrakóngur. This beast was depicted as a polar bear with "ruddy cheeks" and a unicorn-like horn, which glows in the dark. The king could understand when humans talk and was considered to be very astute.[198] Two Norwegian fairy tales, "East of the Sun and West of the Moon" and "White-Bear-King-Valemon", involve white bears turning into men and seducing women.[199]
Drawings of polar bears have been featured on maps of the northern regions. Possibly the earliest depictions of a polar bear on a map is the Swedish Carta marina of 1539, which has a white bear on Iceland or "Islandia". A 1544 map of North America includes two polar bears near Quebec. Notable paintings featuring polar bears include François-Auguste Biard's Fighting Polar Bears (1839) and Edwin Landseer's Man Proposes, God Disposes (1864). Polar bears have also been filmed for cinema. An Inuit polar bear hunt was shot for the 1932 documentary Igloo, while the 1974 film The White Dawn filmed a simulated stabbing of a trained bear for a scene. In the film The Big Show (1961), two characters are killed by a circus polar bear. The scenes were shot using animal trainers instead of the actors. In modern literature, polar bears have been characters in both children's fiction, like Hans Beer's Little Polar Bear and the Whales and Sakiasi Qaunaq's The Orphan and the Polar Bear, and fantasy novels, like Philip Pullman's His Dark Materials series. In radio, Mel Blanc provided the vocals for Jack Benny's pet polar bear Carmichael on The Jack Benny Program.[200] The polar bear is featured on flags and coats of arms, like the coat of arms of Greenland, and in many advertisements, notably for Coca-Cola since 1922.[201]
As charismatic megafauna, polar bears have been used to raise awareness of the dangers of climate change. Aurora the polar bear is a giant marionette created by Greenpeace for climate protests.[202] The World Wide Fund for Nature has sold plush polar bears as part of its "Arctic Home" campaign.[203] Photographs of polar bears have been featured in National Geographic and Time magazines, including ones of them standing on ice floes, while the climate change documentary and advocacy film An Inconvenient Truth (2006) includes an animated bear swimming.[202] Automobile manufacturer Nissan used a polar bear in one of its commercials, hugging a man for using an electric car.[204] To make a statement about global warming, in 2009 a Copenhagen ice statue of a polar bear with a bronze skeleton was purposely left to melt in the sun.[205]
See also
- 2011 Svalbard polar bear attack
- International Polar Bear Day
- List of individual bears – includes individual captive polar bears
- Polar Bears International – conservation organization
- Polar Bear Shores – an exhibit featuring polar bears at Sea World in Australia
Notes
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