User:Eliezg/Sandbox
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[edit] A proposal for restructuring the second half of Polar Bear
[edit] Exploitation
[edit] Indigeneous people
Polar bear have long provided important raw materials for Arctic peoples, and almost all parts of captured animals was used.[1] The fur was used in particular to sew pants 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 gall bladder and sometimes heart were dried and powdered for medicinal purposes; the large canines were highly valued as talismans.[2] Only the liver was not used, as its high concentration of vitamin A is poisonous.[3] Indeed, hunters make sure to either toss the liver into the sea or bury it in order to spare their dogs from potential poisoning.[2] Traditional subsistence hunting was on a small enough scale to not significantly affect polar bear populations, mostly because of the sparseness of the human population in polar bear habitat.[4]
[edit] History of commercial harvest
In Russia, polar bear furs were already being commercially traded in the 14th century, though it was of relatively low value compared to arctic fox or even reindeer fur.[2] The growth of the human population in the Eurasian arctic in the 16th and 17th century, together with the advent of firearms and increasing trade, dramatically increased the harvest of polar bears.[5][6]. However, since polar bear fur has always played a marginal commercial role, data on the historical harvest is fragmentary. It is known, for example, that already in the winter of 1784/1785 Russian Pomors on Spitzbergen harvested 150 polar bears on Magdalena fjord.[2] In the early 20th century, Norwegian hunters were harvesting 300 bears a year at the same location. Estimates of total historical harvest suggest that from the beginning of the 18th century, roughly 400-500 animals were being harvested annually in northern Eurasia, reaching a peak of 1,300 to 1,500 animals in the early 20th century, and falling off as the numbers began dwindling.[2]
In the first half of the 20th century, mechanized and overpoweringly efficient methods of hunting and trapping came into use in North America as well.[7] Polar bears were chased from snowmobiles, icebreakers, and airplanes, the latter practice described in a 1965 New York Times editorial as being "about as sporting as machine gunning a cow."[7] The numbers taken grew rapidly in the 1960s, peaking around 1968 with a global total of 1,250 bears that year.[8]
[edit] Contemporary regulations
Concerns over the future survival of the species led to the development of international regulations on polar bear hunting. Norway passed a series of increasingly strict regulations from 1965 to 1973, and has completely banned hunting since then. The Soviet Union banned all commercial hunting outright in 1955. Canada began imposing hunting quotas in 1968. The U.S. began regulating in 1971 and adopted the Marine Mammal Protection Act in 1972. In 1973, the International Agreement on the Conservation of Polar Bears, also known as the Oslo Agreement, was signed by all five nations whose territory is inhabited by polar bears. Although the agreement is not enforceable in itself, member countries agreed to place restrictions on recreational and commercial hunting, completely ban hunting from aircraft and icebreakers, and conduct further research.[9] The treaty allows hunting "by local people using traditional methods," although this has been liberally interpreted by member nations.
[edit] Russia
The Soviet Union declared a complete protection in 1955,[5] but allows hunting by the indigenous people on the basis that it is part of their culture. It signed the "Agreement between the Government of the United States of America and the Government of the Russian Federation on the Conservation and Management of the Alaska-Chukotka Polar Bear Population" in October 2000.
[edit] Greenland
In Greenland, restrictions for the species were first introducted in 1994 and expanded by executive order in 2005.[10] Until 2005, Greenland placed no limit on hunting by indigenous people. It imposed a limit of 150 for 2006. It also allowed recreational hunting for the first time.[11] Other provisions included year-round protection of cubs and mothers, restrictions on weapons used, and various administrative requirements to catalogue kills.[10]
[edit] Canada and the United States
About 500 bears are killed per year by humans across Canada,[12] a rate believed by scientists to be unsustainable for some areas, notably Baffin Bay.[13] Canada has allowed sport hunters accompanied by local guides and dog-sled teams since 1970,[14] but the practice was not common until the 1980s.[15] The guiding of sport hunters provides meaningful employment and an important source of income for native communities in which economic opportunities are few.[16] Sport hunting can bring CDN$20,000 to $35,000 per bear into northern communities, mostly from American hunters.[17]
The 1972 United States Marine Mammal Protection Act prohibits the harassment, injuring or killing of any marine mammal species, including polar bears. It also prohibits the importation of products made from polar bears. In 1994, legislation was modified to allow issuing import permits for sport-hunted polar bear trophies, thereby allowing Americans to bring back trophies from hunting expeditions in Canada. The permits are issued by the U. S. Fish and Wildlife Service, which requires that the bear be taken from an area with quotas based on sound management principles.[18] Since 1994, more than 800 sport-hunted polar bear trophies have been imported into the U.S.[19] In 2007, the proposed Polar Bear Protection Act was introduced to reverse the 1994 legislation and ban the importation of dead polar bears; the proposal was defeated.[20][21]
Ironically, because of the way polar bear hunting quotas are managed in Canada, attempts to discourage sport hunting would actually increase the number of bears killed in the short term.[16] Canada allocates a certain number of permits each year to sport and subsistence hunting, and those that are not used for sport hunting are re-allocated to native subsistence hunting. Approximately 50% of sport hunters with permits actually kill a polar bear, whereas for subsistence hunters the success rate is 100%.[16]
The territory of Nunavut accounts for 80% of Canadian kills.[12] The Nunavut government has condemned the American initiative to grant threatened status to polar bears,[22] and northern residents are strongly concerned about it.[23] In 2005, the government of Nunavut increased the quota from 400 to 518 bears,[24] despite protests from some scientific groups.[25] While most of that quota is hunted by the indigenous Inuit people, a growing share is sold to recreational hunters. (0.8% in the 1970s, 7.1% in the 1980s, and 14.6% in the 1990s)[15] Nunavut polar bear biologist, M.K. Taylor, who is responsible for polar bear conservation in the territory, insists that bear numbers are being sustained under current hunting limits.[26] The Government of the Northwest Territories maintain their own quota of 72–103 bears within the Inuvialuit communities of which some are set aside for sports hunters.
[edit] Conservation status, efforts and controversies
The World Conservation Union (IUCN) listed polar bears as a vulnerable species in May 2006.[27] It cited a "suspected population reduction of >30% within three generations (45 years)", due primarily to global warming.[28] Other risks to the polar bear include pollution in the form of toxic contaminants, conflicts with shipping, stresses from recreational polar-bear watching, and oil and gas exploration and development.[28] The IUCN also cited a "potential risk of over-harvest" through legal and illegal hunting.[28]
[edit] Global warming
The World Conservation Union, International Arctic Science Committee, and many leading polar bear biologists have expressed grave concerns about the impact of global warming, including the belief that the species is unlikely to survive if current warming trends continue.[29][30][31][32][33][34]
The key danger to polar bears is malnutrition or starvation due to habitat loss: Polar bears hunt seals from a platform of sea ice. Rising temperatures cause the sea 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.[35] Reduction in sea-ice cover also forces bears to swim longer distances, which further depletes their energy stores and occasionally leads to drowning.[36] To carry a pregnancy to term and nurse a young litter, an adult female must gain at least 200 kg before entering her maternity den.[37] Insufficient nourishment leads to lower reproductive rates in adult females and lower survival rates in cubs and juvenile bears, in addition to poorer body condition in bears of all ages.[33] The effects of global warming are most profound in the southern part of the polar bear's range, and this is indeed where significant degradation of local populations has been observed.[34] A study by the Canadian Wildlife Service indicated that between 1981 and 1988, shorter periods of sea-ice cover led to a 22% decline in the Hudson Bay subpopulation.[35][38]
The United States Geological Survey stated in November 2006, that the Arctic shrinkage in the Alaskan portion of the Beaufort Sea has led to a higher death rate for polar bear cubs.[39] In Alaska, changes in sea ice conditions have already forced pregnant polar bears to dig their maternity dens on land rather than on pack ice.[40] Recently, polar bears in the Arctic have undertaken longer than usual swims to find prey, resulting in four recorded drownings in the unusually large ice pack regression of 2005.[36]
The United States Geological Survey predicts two-thirds of the world's polar bears will disappear by 2050, based on moderate projections for the shrinking of summer sea ice caused by global warming.[41] The bears would disappear from Europe, Asia, and Alaska, and be depleted from the Arctic archipelago of Canada and areas off the northern Greenland coast. By 2080, they would disappear from Greenland entirely and from the northern Canadian coast, leaving only dwindling numbers in the interior Arctic archipelago.[41] Global warming has already had an impact on polar bear population health and size. Recent declines in polar bear numbers can be linked to the retreat of sea ice and its formation later in the year.[42] The latest estimate of the IUCN is that 7 out of 19 subpopulations are declining or already severely reduced.[10]
Predictions differ on the extent to which polar bears could adapt to climate change by switching to terrestrial food sources. Mitchell Taylor, the Nunavut Government Manager of Wildlife Research, wrote to the U.S. Fish and Wildlife Service arguing that local studies are insufficient evidence for global protection at this time. The letter stated, "At present, the polar bear is one of the best managed of the large Arctic mammals. If all Arctic nations continue to abide by the terms and intent of the Polar Bear Agreement, the future of polar bears is secure…. Clearly polar bears can adapt to climate change. They have evolved and perisisted for thousands of years in a period characterized by fluctuating climate."[26] Ken Taylor, deputy commissioner for Alaska's Department of Fish and Game, has said, "I wouldn't be surprised if polar bears learned to feed on spawning salmon like grizzly bears."[16] However, many scientists consider these theories to be naive.[16]; it is noted that black and brown bears at high latitudes are smaller than elsewhere, because of the scarcity of terrestrial food resources.[43] The IUCN wrote:
| “ | Polar bears exhibit low reproductive rates with long generational spans. These factors make facultative adaptation by polar bears to significantly reduced ice coverage scenarios unlikely. Polar bears did adapt to warmer climate periods of the past. Due to their long generation time and the current greater speed of global warming, it seems unlikely that polar bear will be able to adapt to the current warming trend in the Arctic. If climatic trends continue polar bears may become extirpated from most of their range within 100 years.[28] | ” |
[edit] Pollution
Polar bears accumulate high levels of artificial halocarbons such as PCBs and pesticides because of their diet. Their position at the top of the food pyramid tends to concentrate pollutants, particularly halocarbons because of their lipophilicity: halocarbons are soluble in the blubber which makes up the bulk of the polar bear's diet. Halocarbons 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. The overall significance to population health is uncertain because of unique features of polar bear biology such as summertime fasting. PCBs have received the most study, and they have been associated with birth defects and immune system deficiency.[44] Polar bears in Svalbard have the highest concentrations of PCBs, and biologists suggest this may explain the high incidence of hermaphroditic bears in the area.[45]
The relevant chemicals have been classified as persistent organic pollutants by the United Nations, with the aim of discouraging their production. The most notorious of these, PCBs, DDT and others, have been banned, but their concentrations in polar bear tissues continued to rise for decades after the ban as these chemicals spread upwards on the food pyramid. The most recent data now indicates a decreasing trend.[46]
[edit] Controversy over species protection
Warnings about the future of the polar bear are often contrasted with the fact that worldwide population estimates have increased over the past 50 years and are relatively stable today. [47][48] Some estimates of the global population are around 5,000–10,000 in the early 1970s[49][50]; other estimates were 20,000–40,000 during the 1980s.[5] Current estimates put the global population at between 20,000 and 25,000.[10] 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.[51][52] Second, controls of harvesting were introduced that allowed this previously-overhunted species to recover.[51] Third, the recent effects of global warming have affected sea ice abundance in different areas to varying degrees.[51] Long-term studies of local populations of polar bears show they have been shrinking in the Western Hudson Bay and Baffin Bay areas, and are under stress in the Southern Beaufort Sea area.[13] In the Western Hudson Bay region, for example, there were an estimated 1,194 polar bears in 1987, and 935 in 2004[38]–though there were an estimated 500 polar bears there in 1981.[53]
The accuracy of current population estimates has been challenged. The tracking of bears requires flying a helicopter in a difficult climate, shooting a tranquilizer dart at the bear to sedate it, and then tagging the bear.[16] Modern tracking techniques, which have been implemented only since the mid-1980s, are therefore extremely expensive and difficult to perform consistently over a large area.[16] Some Inuit are skeptical of conservation concerns because of increases in bear sightings near settlements in recent years.[29] Scientists have responded by noting that hungry bears may be congregating around human settlements, leading to the illusion that populations are higher than they actually are.[16]
[edit] Listing under the Endangered Species Act
In February 2005, the Center for Biological Diversity petitioned the U.S. Fish and Wildlife Service to list the bears as as threatened species under the Endangered Species Act.[54] The agency did not respond to the petition, despite being required to do so within 90 days.[54] On 14 December 2006 the Center for Biological Diversity, Greenpeace and the Natural Resources Defense Council filed a successful lawsuit to compel a decision.[55]
On January 9, 2007, the U.S. Fish and Wildlife Service formally proposed to list the polar bear as a threatened species. A final decision was due on January 9, 2008, at which time the agency said it needed another month. On March 7 2008, the inspector general of the U.S. Interior Department began a preliminary investigation into why the decision had been delayed for nearly two months.[56] The investigation is in response to a letter signed by six environmental groups that U.S. Fish and Wildlife Director Dale Hall violated the agency's scientific code of conduct by delaying the decision unnecessarily, allowing the government to proceed with an auction for oil and gas leases in the Alaska's Chukchi Sea, an area of key habitat for polar bears.[56] The auction took place in early February 2008.[56] Hall denied any political interference in the decision and said that the delay was needed to make sure the decision was in a form easily understood.[56]
If listed, the polar bear would be only the third species, after the elkhorn coral and the staghorn coral protected under the Endangered Species Act due to global warming.
[edit] Polar bears and human culture
[edit] Indigenous folklore
For the indigenous peoples of the Arctic, including the Inuit, Yupik, Chukchi, Nentets, Russian Pomors and others, polar bears have long played an important cultural and material role.[1][2] Polar bear remains have been found at hunting sites dating to 2,500 to 3,000 years ago[4] and 1500 year old cave paintings of polar bears have been found in Chukotka.[2] Indeed, it has been suggested that Arctic peoples' skills in seal hunting and snowhouse construction has been in part acquired from the polar bears themselves.[2]
The Inuit have many folk tales featuring the bears including legends in which the bears shed their skins to become men and stories of how the constellation which is said to be a great bear surrounded by dogs came into being.
Among the Chukchi and Yupik of eastern Siberia, there was a longstanding shamanistic ritual of "thanksgiving" to the hunted polar bear. After hunting a polar bear, its head and skin were removed and cleaned and traditionally brought into the home, there was a feast in the hunting camp in its honor. In order to appease the spirit of the bear, there were traditional song and drum music and the skull would be ceremonially fed and offered a pipe.[57] Only once the spirit was appeased, would the skull be separated from the skin, taken beyong the bounds of the homestead, and placed in the ground, facing North.[2] Many of these traditions have faded somewhat in time, especially in light of the total hunting ban in the Soviet Union since 1955.
The Nenets of north central Siberia placed particular value on the talismanic power of the prominent canines. They were traded in the villages of the lower Yenisei and Khatanga rivers to the forest-dwelling peoples further south, who would sew them into their hats as protection against brown bears. 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).[2] The skulls of killed polar bears were buried to specific sacred sites and construct altars, called sedyangi, out of the skulls. Several such sites have been preserved on the Yamal Peninsula.[2]
[edit] As symbols and mascots
Their distinctive appearance and their association with the Arctic have made polar bears popular icons, especially in those areas where they are native. The Canadian 2-dollar coin features the image of a polar bear and both the Northwest Territories and Nunavut in Canada have a licence plate in the shape of a polar bear. The A polar bear is the mascot of Bowdoin College in Maine and was chosen as mascot for the 1988 Winter Olympics held in Calgary.
Companies such Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of the polar bear in advertising,[58] while Fox's Glacier Mints have featured a polar bear named Peppy as the brand mascot since 1922.
[edit] In literature
Polar bears are also popular in fiction, particularly in books aimed at children or young adults. The book, The Polar Bear Son, is adapted from a traditional Inuit tale.[59] They feature prominently in North Child by Edith Pattou, and the Raymond Briggs book The Bear. The panserbjørne of Philip Pullman's fantasy trilogy His Dark Materials are sapient, dignified polar bears who exhibit anthropomorphic qualities. They feature prominently in the 2007 film adaptation of the The Golden Compass, while the TV series Lost has shown polar bears on a mysterious tropical island.
