Polar bears are a potentially endangered species living in the circumpolar north. They are animals which know no boundaries. They pad across the ice from Russia to Alaska, from Canada to Greenland and onto Norway's Svalbard archipelago. No adequate census exists on which to base a worldwide population estimate, but biologists use a working figure of 20,000 to 25,000 bears with about sixty percent of those living in Canada.
In areas where long-term studies are available, populations are showing signs of stress due to shrinking sea ice. Canada's Western Hudson Bay population has dropped 22% since the early 1980s. The declines have been directly linked to an earlier ice break-up on Hudson Bay. A long-term study of the Southern Beaufort Sea population, which spans the northern coast of Alaska and western Canada, has revealed a decline in cub survival rates and in the weight and skull size of adult males. Such declines were observed in Western Hudson Bay bears prior to the population drop there. Another population listed as declining is Baffin Bay. According to the most recent report from the Polar Bear Specialist Group, the harvest levels from Nunavut when combined with those from Greenland (which were thought to be much lower than they actually are) has resulted in this shared population being in a non-sustainable harvest situation, meaning the population is at great risk of a serious decline. The harvest is thought to be several times above what is sustainable.
The IUCN Polar Bear Specialist Group reclassified the polar bear as a vulnerable species on the IUCN's Red List of Endangered Species at their most recent meeting (Seattle, 2005). They reported that of the 19 subpopulations of polar bears, five are declining, five are stable, two are increasing, and seven have insufficient data on which to base a decision. On May 14, 2008, the U.S. Department of the Interior reclassified the polar bear as a Threatened Species under the Endangered Species Act, citing concerns about sea ice loss. Canada and Russia list the polar bear as a "species of concern."
Some Native communities in Canada have been reporting increasing numbers of polar bears on land. Traditional hunters believe this indicates an increased population, although the increased presence on land may, in fact, be related to shrinking sea ice and changes in the bears' distribution patterns. Data is needed to understand the change. The U.S. Fish and Wildlife Service states, "In the declining polar bear population of Canada's Western Hudson Bay, extensive scientific studies have indicated that the increased observation of bears on land is a result of changing distribution patterns and a result of changes in the accessibility of sea ice habitat."
Climate change is the main threat to polar bears today. A diminishing ice pack directly affects polar bears, as sea ice is the platform from which they hunt seals. Although the Arctic has experienced warm periods before, the present shrinking of the Arctic's sea ice is rapid and unprecedented.
In the 1960s and 1970s, hunting was the major threat to the bears. At the time, polar bears were under such severe survival pressure from hunters that a landmark international accord was reached, despite the tensions and suspicions of the Cold War. The International Agreement on the Conservation of Polar Bears was signed in Oslo, November 15, 1973 by the five nations with polar bear populations: Canada, Denmark (Greenland, Norway, the U.S., and the former U.S.S.R.
The polar bear nations agreed to prohibit random, unregulated sport hunting of polar bears and to outlaw hunting the bears from aircraft and icebreakers as had been common practice. The agreement also obliged each nation to protect polar bear denning areas and migration patterns and to conduct research relating to the conservation and management of polar bears. Finally, the nations agreed to share their polar bear research findings with each other. Member scientists of the Polar Bear Specialist Group now meet every three to four years under the auspices of the IUCN World Conservation Union to coordinate their research on polar bears throughout the Arctic.
The Oslo agreement was one of the first and most successful international conservation measures enacted in the 20th century. Its legacy continues today, with member scientists from each nation continuing to work together in face new threats to the bears including climate change, pollution, industrial activities, and poaching.
Polar bears are well-adapted to severe cold. Winter temperatures in the far north often plunge to -40° F or -50° F and can stay that way for days or even weeks.
In January and February, the average temperature in the high Arctic is -29° F.
The Arctic stays black and fiercely cold for months on end. In the High Arctic, the sun sets in October and does not rise again until late February.
The word "Arctic" comes from the ancient Greek Arktikos, or "country of the great bear." Though the Greeks had no knowledge of the polar bear, they named the region after the constellation Ursus Major, the Great Bear, found in the Northern Sky.
A thick layer of blubber (up to 4.5 inches thick) provides polar bears with such excellent insulation that their body temperature and metabolic rate remain the same even at -34°F.
A polar bear's body temperature is 98.6°, which is average for mammals.
On bitterly cold days with fierce winds, polar bears dig out a shelter in a snow bank and curl up in a tight ball to wait out the storm.
When curled up in a ball, polar bears sometimes cover their muzzles — which radiate heat — with one of their thickly furred paws.
Polar bears know how to pack on the fat: A single bear can consume 100 pounds of blubber at one sitting.
The polar bear's compact ears and small tail also help prevent heat loss.
Polar bears have two layers of fur for further protection from the cold.
Polar bears have more problems with overheating than they do with cold. Even in very cold weather, they quickly overheat when they try to run.
The unregulated hunting of polar bears was ended more than 30 years ago by an international agreement among the polar bear nations. But legal hunting continues to kill more than 700 polar bears a year. Most harvesting is conducted by indigenous peoples for whom hunting is an important cultural activity and a source of income.
In the United States, only Alaskan natives can hunt polar bears. While there is no legal requirement for a quota, many native areas take only male bears. In Danish Greenland, natives take polar bears in subsistence hunts for food and hides. In Norway, polar bears are protected from all forms of hunting.
Canada allows natives to hunt polar bears under a quota system that divides permits among native communities. However, Canada is the only nation that allows sport or trophy hunting by non-natives and non-citizens. This enables native hunters to sell their permits to sport hunters for large sums, a windfall for communities that have no other source of income. To take their trophies out of Canada, U. S. hunters must obtain an import permit from the U. S. Fish and Wildlife Service, which, in turn, requires that Canadian quotas be based on sound management principles. To set quotas, wildlife managers must conduct accurate population surveys of polar bears. In the past, lack of data has allowed quotas to be set at dangerously high levels. Thus, it is important that Canada carry out a timely and accurate census of polar bear numbers to allow quotas to be set at safe and realistic levels.
In Russia, polar bears have long enjoyed protection from hunting of any kind. As Russia shares a population of polar bears with the United States, the two governments and native groups in the Russian Far East and Alaska drafted and signed an international treaty, ratified by the U.S. Senate, which allows hunting by Russian natives and places quota restrictions on both U.S. and Russian natives. The treaty calls for the application of game management principles and allocation of quotas between villages. A major problem in the Russian Far East is the lack of adequate law enforcement. As a consequence, poaching of polar bears has become widespread. For the treaty to be effective, poaching must be stopped.
The key to the regulation of hunting according to game management principles is a reliable knowledge of polar bear numbers. Population estimates for the Circumpolar North range from 16,000 to 35,000 bears. The figure of 22,000 is accepted as a working number. Scientists agree that in many areas, data are lacking entirely. For serious protection of polar bears, the five polar bear nations must conduct a thorough and ongoing census of polar bears. At present, the polar bear is classified as a potentially threatened species rather than endangered, but careful management is necessary in order for that status to remain.
In areas where long-term studies are available, populations are showing signs of stress due to shrinking sea ice. Canada's Western Hudson Bay population has dropped 22% since the early 1980s. The declines have been directly linked to an earlier ice break-up on Hudson Bay. A long-term study of the Southern Beaufort Sea population, which spans the northern coast of Alaska and western Canada, has revealed a decline in cub survival rates and in the weight and skull size of adult males. Such declines were observed in Western Hudson Bay bears prior to the population drop there. Another population listed as declining is Baffin Bay. According to the most recent report from the Polar Bear Specialist Group, the harvest levels from Nunavut when combined with those from Greenland (which were thought to be much lower than they actually are) has resulted in this shared population being in a non-sustainable harvest situation, meaning the population is at great risk of a serious decline. The harvest is thought to be several times above what is sustainable.
The IUCN Polar Bear Specialist Group reclassified the polar bear as a vulnerable species on the IUCN's Red List of Endangered Species at their most recent meeting (Seattle, 2005). They reported that of the 19 subpopulations of polar bears, five are declining, five are stable, two are increasing, and seven have insufficient data on which to base a decision. On May 14, 2008, the U.S. Department of the Interior reclassified the polar bear as a Threatened Species under the Endangered Species Act, citing concerns about sea ice loss. Canada and Russia list the polar bear as a "species of concern."
Some Native communities in Canada have been reporting increasing numbers of polar bears on land. Traditional hunters believe this indicates an increased population, although the increased presence on land may, in fact, be related to shrinking sea ice and changes in the bears' distribution patterns. Data is needed to understand the change. The U.S. Fish and Wildlife Service states, "In the declining polar bear population of Canada's Western Hudson Bay, extensive scientific studies have indicated that the increased observation of bears on land is a result of changing distribution patterns and a result of changes in the accessibility of sea ice habitat."
Climate change is the main threat to polar bears today. A diminishing ice pack directly affects polar bears, as sea ice is the platform from which they hunt seals. Although the Arctic has experienced warm periods before, the present shrinking of the Arctic's sea ice is rapid and unprecedented.
In the 1960s and 1970s, hunting was the major threat to the bears. At the time, polar bears were under such severe survival pressure from hunters that a landmark international accord was reached, despite the tensions and suspicions of the Cold War. The International Agreement on the Conservation of Polar Bears was signed in Oslo, November 15, 1973 by the five nations with polar bear populations: Canada, Denmark (Greenland, Norway, the U.S., and the former U.S.S.R.
The polar bear nations agreed to prohibit random, unregulated sport hunting of polar bears and to outlaw hunting the bears from aircraft and icebreakers as had been common practice. The agreement also obliged each nation to protect polar bear denning areas and migration patterns and to conduct research relating to the conservation and management of polar bears. Finally, the nations agreed to share their polar bear research findings with each other. Member scientists of the Polar Bear Specialist Group now meet every three to four years under the auspices of the IUCN World Conservation Union to coordinate their research on polar bears throughout the Arctic.
The Oslo agreement was one of the first and most successful international conservation measures enacted in the 20th century. Its legacy continues today, with member scientists from each nation continuing to work together in face new threats to the bears including climate change, pollution, industrial activities, and poaching.
Polar bears are well-adapted to severe cold. Winter temperatures in the far north often plunge to -40° F or -50° F and can stay that way for days or even weeks.
In January and February, the average temperature in the high Arctic is -29° F.
The Arctic stays black and fiercely cold for months on end. In the High Arctic, the sun sets in October and does not rise again until late February.
The word "Arctic" comes from the ancient Greek Arktikos, or "country of the great bear." Though the Greeks had no knowledge of the polar bear, they named the region after the constellation Ursus Major, the Great Bear, found in the Northern Sky.
A thick layer of blubber (up to 4.5 inches thick) provides polar bears with such excellent insulation that their body temperature and metabolic rate remain the same even at -34°F.
A polar bear's body temperature is 98.6°, which is average for mammals.
On bitterly cold days with fierce winds, polar bears dig out a shelter in a snow bank and curl up in a tight ball to wait out the storm.
When curled up in a ball, polar bears sometimes cover their muzzles — which radiate heat — with one of their thickly furred paws.
Polar bears know how to pack on the fat: A single bear can consume 100 pounds of blubber at one sitting.
The polar bear's compact ears and small tail also help prevent heat loss.
Polar bears have two layers of fur for further protection from the cold.
Polar bears have more problems with overheating than they do with cold. Even in very cold weather, they quickly overheat when they try to run.
The unregulated hunting of polar bears was ended more than 30 years ago by an international agreement among the polar bear nations. But legal hunting continues to kill more than 700 polar bears a year. Most harvesting is conducted by indigenous peoples for whom hunting is an important cultural activity and a source of income.
In the United States, only Alaskan natives can hunt polar bears. While there is no legal requirement for a quota, many native areas take only male bears. In Danish Greenland, natives take polar bears in subsistence hunts for food and hides. In Norway, polar bears are protected from all forms of hunting.
Canada allows natives to hunt polar bears under a quota system that divides permits among native communities. However, Canada is the only nation that allows sport or trophy hunting by non-natives and non-citizens. This enables native hunters to sell their permits to sport hunters for large sums, a windfall for communities that have no other source of income. To take their trophies out of Canada, U. S. hunters must obtain an import permit from the U. S. Fish and Wildlife Service, which, in turn, requires that Canadian quotas be based on sound management principles. To set quotas, wildlife managers must conduct accurate population surveys of polar bears. In the past, lack of data has allowed quotas to be set at dangerously high levels. Thus, it is important that Canada carry out a timely and accurate census of polar bear numbers to allow quotas to be set at safe and realistic levels.
In Russia, polar bears have long enjoyed protection from hunting of any kind. As Russia shares a population of polar bears with the United States, the two governments and native groups in the Russian Far East and Alaska drafted and signed an international treaty, ratified by the U.S. Senate, which allows hunting by Russian natives and places quota restrictions on both U.S. and Russian natives. The treaty calls for the application of game management principles and allocation of quotas between villages. A major problem in the Russian Far East is the lack of adequate law enforcement. As a consequence, poaching of polar bears has become widespread. For the treaty to be effective, poaching must be stopped.
The key to the regulation of hunting according to game management principles is a reliable knowledge of polar bear numbers. Population estimates for the Circumpolar North range from 16,000 to 35,000 bears. The figure of 22,000 is accepted as a working number. Scientists agree that in many areas, data are lacking entirely. For serious protection of polar bears, the five polar bear nations must conduct a thorough and ongoing census of polar bears. At present, the polar bear is classified as a potentially threatened species rather than endangered, but careful management is necessary in order for that status to remain.
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