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'''''Þar sem djöflaeyjan rís''''' er [[skáldsaga]] eftir [[Einar Kárason]] sem kom fyrst út [[1983]] og fjallar um líf fjölskyldu sem býr í [[braggahverfi]] á [[Ísland]]i á umrótstímum fyrstu áranna eftir [[Síðari heimsstyrjöldin]]a. Bókin er fyrsti hlutinn af [[þríleikur|þríleik]] sem stundum hefur verið kallaður ''[[Eyjabækurnar]]''. Sjálfstætt framhald hennar kom út í bókunum ''[[Gulleyjan (Einar Kárason)|Gulleyjan]]'' ([[1985]]) og ''[[Fyrirheitna landið (Einar Kárason)|Fyrirheitna landið]]'' ([[1989]]).
Polar Bear
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This article is about the animal. For other uses, see Polar Bear (disambiguation).
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Polar bear
[[Friðrik Þór Friðriksson]] gerði [[Þar sem djöflaeyjan rís (kvikmynd)|samnefnda kvikmynd]] eftir sögunni árið [[1996]].
Conservation status
{{bókmenntastubbur}}
Vulnerable (IUCN) [1]
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Ursidae
Genus: Ursus
Species: U. maritimus
Binomial name
Ursus maritimus
Phipps, 1774
[[Flokkur:Íslenskar skáldsögur]]
Polar bear range
Synonyms
Thalarctos maritimus
The polar bear (Ursus maritimus), also known as the white bear, northern bear, sea bear, ice bear or nanuq in some Inuit languages, is a species of bear that is native to the Arctic and the apex predator within its range. Its thick blubber and fur insulate it against the cold. Its fur, commonly mistaken as white or cream-colored due to the way light refracts within each hair, is translucent, providing camouflage from its prey. The bear has a short tail and small ears that help reduce heat loss, as well as a relatively small head and long, tapered body to streamline it for swimming. The polar bear is a semi-aquatic marine mammal that depends mainly upon the pack ice and the marine food web for survival. It has uniquely adapted for life on a combination of land, sea, and ice and is now dependent on this combination.[2]
Scientists and climatologists believe that the projected decreases in the polar sea ice due to global warming will have a significant negative impact or even lead to extinction of this species within this century.[1][3]
An alternative theory downplays the effect climate change is having on the polar bear and hypothesizes that the species may survive through adaptation. [4]
Contents [hide]
1 Physical description
1.1 Size and weight
1.2 Fur and skin
2 Evolution
2.1 Speciation
2.2 Subspecies and populations
3 Natural range
4 Hunting, diet and feeding
5 Breeding
6 Conservation status
7 Threats natural and unnatural
8 Entertainment and commerce
9 Trivia
10 Gallery
11 References
12 See also
13 External links
Physical description
Size and weight
Polar bears rank with the Kodiak bear as among the largest living land carnivores, and male polar bears may weigh twice as much as a Siberian tiger. There is great sexual dimorphism, with some males reaching more than twice the size of the females. Most adult males weigh 300-600 kg (660-1320 lbs) and measure 2.4-3.0 m (7.9-10.0 ft) in length. Adult females are roughly half the size of males and normally weigh 150-300 kg (330-660 lbs), measuring 1.9-2.1 m (6.25-7 ft).[5][6] At birth, cubs weigh only 600-700 g or about a pound and a half.
Fur and skin
A Polar Bear resting.In addition to its obvious white hue, a polar bear's fur is translucent and provides good camouflage and insulation. It may yellow with age. Under the fur, the bear has a black skin, which is visible at the nose, eyes, and mouth. Stiff hairs on the pads of its paws provide insulation and traction on ice.
Unlike other Arctic mammals, polar bears do not shed their coat for a darker shade in the summer. It was once conjectured that the hollow hairs of a polar bear coat acted as fiber-optic tubes to conduct light to its black skin, where it could be absorbed - a theory disproved by recent studies.[7] The thick undercoat does, however, insulate the bears: they overheat at temperatures above 10 °C (50 °F), and are nearly invisible under infrared photography; only their breath and muzzles can be easily seen.[8] These bears often sprawl upon the ice to cool off; on land, they may dig for the cooler permafrost layer beneath. Growing through the undercoat is a relatively sparse covering of hollow guard hairs about six inches long. These guard hairs are stiff, shiny and erect, and stop the undercoat from matting when wet. Water is easily shaken off before it can freeze. The bear also rolls in snow to shed moisture from the coat. When kept in captivity in warm, humid conditions, it is not unknown for the fur to turn a pale shade of green. This is due to algae growing in the guard hairs - in unusually warm conditions, the hollow tubes provide an excellent home for algae. Whilst 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 peroxide bleach.
Evolution
Speciation
The raccoon and bear families are believed to have diverged about 30 million years ago. The spectacled bear split from other bears around 13 million years ago. The six distinct ursine species originated some 6 million years ago. According to both fossil and DNA evidence, the polar bear diverged from the brown bear roughly 200 thousand years ago; fossils show that between 10 and 20 thousand years ago the polar bear's molar teeth changed significantly from those of the brown bear.
Polar bears have, however, bred with brown bears to produce fertile grizzly–polar bear hybrids,[9] [10] suggesting that the two are close relatives. But neither species can survive long in the other's niche, and with distinctly different morphology, metabolism, social and feeding behaviors, and other phenotypic characters, the two bears are generally classified as separate species.
In a widely cited paper published in 1996, a comparison of the DNA of various brown bear populations showed that the brown bears of Alaska's ABC islands shared a more recent common ancestor with polar bears than with any other brown bear population in the world.[11] Also to see how the bear species once split yet are still connected, polar bears still have HIT (hibernation induction trigger) in their blood, but do not now utilize this to hibernate as the brown bear does. They may occasionally enter a dormant state referred to as "denning" (pregnant females in particular), though their body temperature does not decrease during this period as it would for a typical mammal in hibernation.[12]
Subspecies and populations
Many sources list no polar bear subspecies,[13] while others list two - Ursus maritimus maritimus and Ursus maritimus marinus.[14][15] The number of populations varies depending upon who is counting. The IUCN/SSC Polar Bear Specialist Group (PBSG), the pre-eminent international scientific body for research and management of polar bears, recognizes twenty populations, or stocks, worldwide.[8] Other scientists recognize six distinct populations.[16]
Chukchi Sea population on Wrangell Island and western Alaska
Northern and northwestern Alaska and northwestern Canada (the Beaufort Sea population)
Canadian Arctic archipelago
Greenland
Spitzbergen-Franz Josef Land
Central Siberia
Natural range
Though it spends time on land and ice, the polar bear is regarded as a marine mammal due to its intimate relationship with the sea.[17] The circumpolar species is found in and around the Arctic Ocean, its southern range limited by pack ice. Their southernmost point is James Bay in Canada. While their numbers thin north of 88 degrees, there is evidence of polar bears all the way across the Arctic. Population is estimated to be between 20,000 to 25,000.[18]
The main population centers are:
Wrangell Island and western Alaska
Northern Alaska
Canadian Arctic archipelago
Greenland
Svalbard-Franz Josef Land
North-Central Siberia
Their range is limited by the availability of that sea ice they use as a platform for hunting seals, the mainstay of their diet. The destruction of its habitat on the Arctic ice threatens the bear's survival as a species; it may become functionally extinct within the century.[19] Signs of this have already been observed at the southern edges of its range.[20] [21]
Polar bear sow and two cubs on Beaufort Sea coast, Alaska
Hunting, diet and feeding
The polar bear is the most carnivorous member of the bear family, and the one that is most likely to prey on humans as food. It feeds mainly on seals, especially ringed seals that poke holes in the ice to breathe, but will eat anything it can kill: birds, rodents, shellfish, crabs, beluga whales, young walruses, occasionally musk oxen or reindeer, and very occasionally other polar bears. Still, reindeer and musk oxen can easily outrun a polar bear, and polar bears overheat quickly: thus the polar bear subsists almost entirely on live seals and walrus calves, or on the carcasses of dead adult walruses or whales. They are enormously powerful predators, but they rarely kill adult walruses, which are twice the polar bear's weight, although this has been known to happen.[22] Orcas, humans, and larger bears of their own species are the only predators of polar bears.
As a carnivore which feeds largely upon fish-eating carnivores, the polar bear ingests large amounts of vitamin A, which is stored in their livers; in the past, humans have been poisoned by eating the livers of polar bears.[23] Though mostly carnivorous, they sometimes eat berries, roots, and kelp in the late summer.
Polar bears are crafty hunters and will wait by the breathing holes of the seals in the ice and wait for them to surface. Sometimes they crawl up to sleeping seals; stopping if the seal wakes; then resuming only to finally leap and catch them. Adult bears mainly eat the skin and blubber, but generally don't eat the organs and muscle. This reduces the need for water as less urea is produced than from a high protein diet. In the winter, when water is hard to find, this helps save energy as well since they need to ingest less snow. They have lowest cholesterol levels when eating many seals, likely because of the plentiful omega-3 fatty acids in the seal blubber.[24] Their cholesterol rises during fasting. Lactating females and young and growing bears will eat entire carcasses, organs and muscle as well, for the higher protein content. Typically the normal adult bear will eat a seal every five days or so when their prey is most plentiful.
Polar bears are excellent swimmers and have been seen in open Arctic waters as far as 60 miles from land. In some cases they spend half their time on ice floes. Their 12 cm (5 in) layer of fat adds buoyancy in addition to insulating them from the cold. 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.[25]
Polar bears at the Toronto ZooPolar bears are enormous, aggressive, curious, and extremely dangerous to humans. Wild polar bears, unlike most other bears, are barely habituated to people and will quickly size up any animal they encounter as potential prey. A polar bear should never be approached and if one is spotted, it is best to retreat slowly on foot to an indoor location, or leave in a vehicle.
Like other bear species, they have developed a liking for garbage as a result of human encroachment. For example, the dump in Churchill, Manitoba is frequently scavenged by polar bears, who have been observed eating, among other things, grease and motor oil.[26].
Breeding
Mother with cub at SvalbardThe polygamous polar bears mate in the spring (March to May); pairing only lasts for the actual mating with few permanent bonds observed. Testosterone levels increase in the spring for the males and the testicles increase in size.[citation needed] Once fertilized the females ova undergoes a delayed implantation, which takes hold in September or October. The gestation period is between 195 and 265 days (about 8 months) with the cubs born soon after the ova implant in early winter (November to December). The mother digs a two-chambered cave in deep snow for the birth in October after a period of heavily feeding. Usually, two cubs are born, less often one or three; litters of four cubs have been recorded. Like other Ursus bears, the new cubs are tiny, typically 30 cm long and weighing 700 g (a pound and a half), compared to their sometimes 300 kg (660 lb) mothers. The helpless and blind cubs open their eyes after about a month, emerge from the den at about 10 kg (22 lb), are able to walk at 1.5 months, and start eating solid food at 4-5 months. They remain with their mother, learning to hunt and protect themselves against adult males, which sometimes cannibalize cubs. Females nurse their young for up to two and a half years on milk that contains approximately 33% fat, higher than that of any other species of bear and comparable to that of other marine mammals.[8] The bears farther north tend to stay longer with their young, with weather conditions and age of the female affect this time as well. Sexual maturity is reached at 3-4 years. Adult polar bears are known to live over 30 years in captivity with average around 25. In the wild this is likely much shorter. Polar bears do not hibernate, though lactating females go into dormancy during denning. The female can control urea cycling so she can endure a long fast during this time[citation needed]; they often go without eating for a period of nine months and rely on stored body fat (also known as blubber) to keep themselves and their cubs alive. Once the cubs mature they go their separate ways.
The 2004 National Geographic study found no cases of cubs being born as triplets, a common event in the 1970s, and that only one in twenty cubs were weaned at eighteen months, as opposed to half of cubs three decades earlier.[21]
In Alaska, the United States Geological Survey reports that 42 percent of cubs now reach 12 months of age, down from 65 percent 15 years ago.[27] In other words, less than two of every three cubs that survived 15 years ago are now making it past their first year.
Conservation status
The population of 20,000-25,000 polar bears has been shrinking. On the west coast of Hudson Bay in Canada, for example, there were an estimated 1200 polar bears in 1987, and 950 in 2007.[28]
In February 2005 the environmental group, Center for Biological Diversity, with support from American senator Joe Lieberman, petitioned the United States Fish and Wildlife Service (FWS), part of the Department of the Interior to use the Endangered Species Act and list the bears as a threatened species. [29]
Under United States law the FWS was required to respond to the petition within 90 days, [29] but in October 2005 after no reply had been received the Center for Biological Diversity threatened to sue the United States Government. On 14 December 2006 the Center for Biological Diversity along with Greenpeace and the Natural Resources Defense Council filed a lawsuit in California. [30]
On December 27, 2006, the United States Department of the Interior in agreement with the three groups proposed that polar bears be added to the endangered species list, the first change of this type to be attributed to global warming. It will take up to a year to make the final determination. [31] The Natural Resources Defense Council contends that though it is "a big step forward" the proposal fails to identify global warming pollution as the cause of rising Arctic temperatures and vanishing sea ice. In addition, it says the proposal offered by Dr. Rosa Meehan, Supervisor of the U.S. Fish and Wildlife Service, does not designate any of the land discussed as the kind of habitat that is essential for the polar bear's survival as "critical habitat" that could help the bear recover. [32][33]
The World Conservation Union had already given polar bears threatened status in May 2006.[34]
There are claims, however, that the local population of polar bears is actually increasing in some areas, especially where seal hunting has been banned.[35] These claims are based on an ongoing survey of the bear population in the Davis Strait by Mitch Taylor, which may confirm local Inuit reports of an increase of polar bears they have seen in the area. However, this Nunavut government funded Taylor study has critics that say the Inuit in this area wish the bears to remain in unprotected status so they can continue to hunt them. Polar bear experts have also stated this is irrelevant to the greater situation, as the seal hunting in this area has been banned, thereby greatly increasing the food supply of the bear and reducing bear/seal hunters' presence, plus it is a limited area.[36]The US FWS has actually stated, that in that area there is not sufficient evidence to make accurate estimates of polar bear population changes.
Threats natural and unnatural
The most immediate and topically recognized threat to the polar bear is the drastic changes taking place in their natural habitat, which is literally melting away due to global warming.[37][38]The United States Geological Survey, for example, in November 2006, stated that the loss of sea ice in the Alaskan portion of the Beaufort Sea has lead to a higher death rate for polar bear cubs.[39]
The Harvard University Gazette said:
A 1999 study of polar bears on Hudson Bay showed that rising temperatures are thinning the pack ice from which the bears hunt, driving them to shore weeks before they've caught enough food to get them through hibernation.[40]
The BBC reported:
Climate change is threatening polar bears with starvation by shortening their hunting season, according to a study by scientists from the Canadian Wildlife Service.[41]
There is also some concern over pollution in addition to the normal natural problems the bears might face.[42] Reduced cub survival has been reported in connection with PCBs, as well as reports of organochlorines affecting the endocrine system and immune systems with lower immunoglobulin G seen with increasing PCB levels.[43][44] The lipophilic PCBs are considered a serious threat to marine mammals generally and to their food web, quickly concentrating into fat and blubber. These and related compounds are known in mammals (including humans) to cause such things as abortion, still births, alteration of the menstrual cycle, poor growth and survival of young, carcinogenicity, immunotoxicity, and even outright lethality. Other classes of organohalogens have been found in polar bears, such as PCDDs, PCDFs, TCPMe and TCPMeOH. Hermaphroditic polar bears[2] have now been observed in less pristine areas. While some countries now ban some of these substances, they are still produced in others, and still end up all over the entire planet including the formerly pristine arctic. Even after the use of these chemicals is stopped, they continue to accumulate up the food chain, including in marine mammals and humans, for some time to come.
The bears sometimes have problems with various skin diseases with dermatitis caused sometimes by mites or other parasites. The bears are especially susceptible to Trichinella, a parasitic roundworm they contract by eating infected seals.[45] Sometimes excess heavy metals have been observed, as well as ethylene glycol (antifreeze) poisoning. Bears exposed to oil and petroleum products lose the insulative integrity of their coats, forcing metabolic rates to dramatically increase to maintain body heat in their challenging environment. Bacterial Leptospirosis, rabies and morbillivirus have been recorded. Interestingly, the bears are thought by some to be more resistant than other carnivores to viral disease.[citation needed] The pollutant effect on the bears' immune systems, however, may end up decreasing their ability to cope with the naturally present immunological threats it encounters, and in such a challenging habitat even minor weaknesses can lead to serious problems and quick death.
Entertainment and commerce
Polar bears have been made both controversial and famous for their distinctive white fur and their habitat. Companies like Coca-Cola, Polar Beverages, Nelvana, Bundaberg Rum and Good Humor-Breyers have used images of this bear in logos. The first has consistently displayed the bears as thriving near penguins, though the animals naturally live in opposite hemispheres. The Canadian 2-dollar coin (right) features the image of a polar bear. The panserbjørne of the fantasy trilogy His Dark Materials are polar bears with human-level intelligence. The TV series Lost has featured polar bears on a mysterious tropical island where they are portrayed as fearsome beasts.
Trivia
On April 25, 2006, the first and only grizzly-polar bear hybrid found in the wild was killed by a sport hunter at Banks Island, Northwest Territories, Canada. An RNA test by Wildlife Genetics International in British Columbia confirmed it was a hybrid, with a polar bear mother and a grizzly bear father.[46] Such hybrids had previously been bred in zoos but they were considered to be a "cryptid" (a hypothesized animal for which there is no proof of existence in the wild).
In April 2003, the American submarine Connecticut (SSN 22) poked its sail and rudder through an area of polar ice between Alaska and the North Pole. According to StrategyPage.com, "A large (700-800 lb) polar bear was seen approaching the sub and loitering for about 40 minutes around the subs rear rudder. It took a bite out of the rudder and, finding it inedible, stayed around the area of broken ice near the rudder for a time, apparently thinking a seal might use it as an air hole. The bear finally left when he heard the noise of an approaching helicopter." Photos of the polar bear at the submarines rudder were taken from the periscope camera and distributed to the media.[47]
In December 2006 the reported world's oldest polar bear turned 40 years old. Debbie the Polar Bear lives at the Assiniboine Park Zoo in Winnipeg, Manitoba. [48]
Gallery
Three Polar Bears investigate the submarine USS Honolulu 280 miles from the North Pole.
Two Polar Bears sparring near Churchill, Manitoba, Canada.
Polar Bear tracks at Svalbard
Tourists watching Polar Bears from a "tundra buggy" near Churchill, Manitoba
Polar Bear cubs
Polar Bear at Cape Churchill (Wapusk-Nationalpark, Manitoba, Canada)
Two Polar Bears at Cape Churchill (Wapusk-Nationalpark, Manitoba, Canada)
A Polar Bear floating at the Henry Doorly Zoo
References
Bears of the World, Terry Domico, Photographs by Terry Domico and Mark Newman, Facts on File, Inc, 1988, hardcover, ISBN 0-8160-1536-8
Arctic Dreams, Barry Lopez, Macmillan 1986, hardcover, ISBN 0-333-42244-9
Marine Mammal Medicine, Leslie Dierauf & Frances Gulland, CRC Press 2001, ISBN 0-8493-0839-9
^ a b Schliebe et al (2006). Ursus maritimus. 2006 IUCN Red List of Threatened Species. IUCN 2006. Retrieved on 09 May 2006. Database entry includes a lengthy justification of why this species is listed as vulnerable.
^ http://animaldiversity.ummz.umich.edu/site/accounts/information/Ursus_maritimus.html
^ Polar bear 'extinct within 100 years'. BBC. Retrieved on 2006-02-01.
^ 'Polar Bear Worries Uncertain'.
^ SeaWorld
^ U.S. Fish and Wildlife Service
^ Is Polar Bear Hair Fiber Optic?, Daniel W. Koon, Applied Optics LP, vol. 37, Issue 15, pp.3198-3200, 1998.
^ a b c Natural history. Center for Biological Diversity (2005-02-15). Retrieved on 2006-07-28.
^ Gunderson, A. 2002. "Ursus maritimus" (On-line), Animal Diversity Web. Accessed July 28, 2006 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Ursus_maritimus.html.
^ Report of wild hybrid bear
^ Lisette P. Waits, Sandra L. Talbot, R.H. Ward and G. F. Shields (April 1998). Mitochondrial DNA Phylogeography of the North American Brown Bear and Implications for Conservation 408-417. Conservation Biology. Retrieved on August 1, 2006.
^ Stirling 1988, Polar Bears...& also... Bruce et al.,1990 in Pharmacol. Biochem. Behav., 35: 705-711.
^ Wildfacts - Polar bear. BBC. Retrieved on 2006-07-28.
^ http://www.itis.usda.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=622083
^ http://www.itis.usda.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=622084
^ Polar Bear FAQ. Polar Bears International. Retrieved on 2006-07-28.
^ US Environmental Protection Agency
^ Bear Facts. Polar Bears International. Retrieved on 2006-07-28.
^ "Global warming has U.S. rethinking polar bear status", CBC Canada, 2006-02-08. Retrieved on 2007-01-08.
^ Polar bears and climate change.
Endangered Species Act Listing Process for Polar Bears Underway. Center for Biological Diversity. Retrieved on 2006-07-28.
Barber, D.G., Iacozza, J. Historical analysis of sea ice conditions in M'Clintock Channel and the Gulf of Boothia, Nunavut : implications for ringed seal and polar bear habitat. Arctic 57(1) Mar. 2004, p. 1-14
Stirling, I., Lunn, N.J. Iacozza, J., Elliott, C., Obbard, M. Polar bear distribution and abundance on the southwestern Hudson Bay coast during open water season, in relation to population trends and annual ice patterns. Arctic 57(1) Mar. 2004, p. 15-26
Stirling, I. Parkinson, C.L. Possible effects of climate warming on selected populations of polar bears (Ursus maritimus) in the Canadian Arctic. Arctic 59(3) Sept. 2006, p. 261-275
^ a b T. Appenzeller and D. R. Dimick, "The Heat is On," National Geographic 206 (2004): 2-75. cited in Flannery, Tim (2005). The Weather Makers. Toronto, Ontario: HarperCollins, 101-103. ISBN 0-00-200751-7.
^ http://www.fws.gov/home/feature/2006/polarbear.pdf
^ http://www.visitandlearn.co.uk/factfiles06/diet3.asp
^ [http://www.omega3sealoil.com/ The Benefits of Omega 3 Fatty Acids found In Seal Oil, as Opposed to Fish and Flaxseed Oils.], by Dr. Cosmas Ho, M.D., C.C.F.P.. Last visit March 8, 2007.
^ Iredale, Will. "Polar bears drown as ice shelf melts", The Sunday Times, 2005-12-18. Retrieved on 2006-07-28.
^ Ed Struzik. "Nanook: In the tracks of the great wanderer" (1987). Equinox 6 (1): 18–30.
^ http://www.nzz.ch/2007/02/04/ws/articleEVLOF.html
^ http://www.nzz.ch/2007/02/04/ws/articleEVLOF.html
^ a b Time to protect polar bears from warming?. MSNBC. Retrieved on 2006-02-01.
^ Activists sue U.S. to protect polar bears. MSNBC. Retrieved on 2006-02-01.
^ U.S. weighs listing polar bear as threatened species. REUTERS. Retrieved on 2006-02-01.
^ http://www.polarbearsos.org/
^ http://www.nrdconline.org/campaign/polarbearsos_0207
^ Release of the 2006 IUCN Red List of Threatened Species reveals ongoing decline of the status of plants and animals. World Conservation Union. Retrieved on 2006-02-01.
^ Polar bear numbers up, but rescue continues. National Post (Canada). Retrieved on 2007-03-06.
^ [1]
^ http://www.feed24.com/go?item_id=36284429&q_orig=2040%20ice-free
^ http://www.usatoday.com/weather/resources/coldscience/2004-11-08-arctic-warming_x.htm
^ Polar bear survival rate falls as climate warms: study. REUTERS. Retrieved on 2006-02-01.
^ (Alvin Powell) March 22, 2001
^ Global warming could starve polar bears. BBC. Retrieved on 2006-03-01.
^ http://www.bbc.co.uk/nature/animals/features/144index.shtml
^ http://www.pwrc.usgs.gov/bioeco/polarbear.htm
^ http://www.ngo.grida.no/wwfap/polarbears/risk/toxic.html
^ http://www.seaworld.org/animal-info/info-books/polar-bear/longevity.htm
^ "Grizzly-Polar Bear Hybrid Found -- But What Does It Mean?", news.nationalgeographic.com, May 16, 2006. Retrieved on 2006-11-01.
^ "Bear Attacks Sub", www.strategypage.com, April 27, 2003. Retrieved on 2007-1-15.
^ Zoological Society of Manitoba
See also
Polar bear hunting
Grizzly-polar bear hybrid
Arctic National Wildlife Refuge
USS Connecticut (SSN-22)
External links
Wikimedia Commons has media related to:
Ursus maritimusWikispecies has information related to:
Ursus maritimusARKive - images and movies of the polar bear (Ursus maritimus)
Smithsonian National Museum of Natural History species account-Polar Bear
Polar Bears turn green in Singapore, a BBC News report
Polar Bears International, a Polar Bear conservation group
The WWF Polar Bear Tracker, follow Polar Bears on Svalbard as they are tracked by satellite.
Polar Cam, live video of the Polar Bear exhibit at the San Diego Zoo. Online daily between 09:00 – 16:00 UTC-8 (or UTC-7 during Daylight saving time)
Pictures of Polar Bears on the island of Spitsbergen
Polar Bear Photo Gallery
CBC News article on possible "grolar bear" (Polar Bear/Grizzly Bear hybrid)
Polar Bear infos - BearPlanet infos and images of Polar Bears
NY Times - Agency Proposes to List Polar Bears as Threatened
[3] polar bear cub called Knut in Berlin zoo
The Taylor study in the seal-hunting-ban area:
Nunatsiaq News, Nunavut paper (from a 90% Inuit community) stating that some Inuit are reporting increased polar bear numbers.
Scienceline reportcannabalism & starvation
nunatsiaq paper report another Nunavut (nunatsiaq is an Inuit word) based newspaper report on polar bear numbers
arctic net
Inuvialuit-Inupiat Management Agreement in the Southern Beaufort Sea 1988 - [4]
Global Warming Issues
List the Polar Bear as a Threatened Species under the Endangered Species Act
Starving polar bears shame Bush to act
Dept of Environment Nunavut info on global warming surveys
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