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Policy and Legislation
Polar Bears on Thin Ice
In Brief: Dramatically rising temperatures in the Arctic are melting the sea ice where polar bears live, hunt, and breed, putting the future of this majestic predator in jeopardy as their habitat melts away.
As global warming causes average temperatures to rise around the world, the effects are being felt most dramatically in the Arctic. In northern latitudes, temperatures are rising at roughly twice the global pace, and average temperatures in the Arctic have risen 4-5 degrees Fahrenheit in the last 50 years. This warming directly influences the surface area and thickness of sea ice, the floating ice that surrounds land masses of the Arctic. While the coverage of sea ice fluctuates seasonally, annual spring ice break-up now occurs earlier, summer melting is more dramatic, and winter freezing occurs later each year. Exposed dark ocean water absorbs more energy than sea ice, leading to a positive feedback system where the Arctic continues to warm dramatically, meaning less sea ice. Recent research has produced models that predict a complete disappearance of summer sea ice within this century. The impact of disappearing sea ice on polar bears, which live, hunt and breed on Arctic sea ice, is grave. The apex of the Arctic food chain, the polar bear depends on sea ice as a platform for hunting ringed seals, its main food source. During summer months polar bears will migrate up to hundreds of kilometers to remain near persistent sea ice. If, as predicted, summer sea ice disappears entirely, the effects will be devastating for polar bear populations across the Arctic. Their habitat is literally melting away. With the spring ice break-up occurring significantly earlier than just a few decades ago, the polar bear's seal hunting season is being cut short. This means that polar bears are finding it harder to build up the energy reserves they need to survive the rest of the year. The effects of this lack of ice on the polar bear populations are clear: the bears are in trouble. Studies have shown a decline in average body size, fertility, and survival rates among young adults and cubs. Even more disturbingly, there have recently been unprecedented numbers of polar bears actually drowning. Less sea ice means more open water and stronger currents, and while polar bears are typically strong swimmers, they are not accustomed to long swims between now infrequent ice platforms. Polar bears drowning from exhaustion signals a significant change in habitat. In addition, recent Canadian and American studies show a spike in instances of cannibalism among polar bears, which is generally extremely rare. On December 27, 2006, after considerable pressure from the scientific and conservation communities, the Bush administration proposed listing the polar bear as "threatened" under the Endangered Species Act due to the effects of melting sea ice. Secretary of the Interior Dirk Kempthorne has acknowledged that warmer Arctic temperatures are eliminating habitat for the polar bear and reducing the abundance of the animals they hunt for food. If protection is granted to this majestic creature, it would be the first time global warming was cited as the primary threat to a species. This marks an important moment for the Bush administration, which has previously been reluctant to recognize that global warming poses a critical and truly global challenge. It is time for our leaders to listen to the American people, and start taking action to combat global warming and to protect species like the polar bear that are suffering from its effects. The public comment period closed on April 9, 2007, and thanks to your support, the U.S. Fish and Wildlife Service recieved over half a million public comments addressing the polar bear's status, including over 16,000 letters sent from Earthjustice supporters! Thank you to all of you who took action to help strengthen the polar bear's case to be listed under the Endangered Species Act! New studies predict polar bears will be gone from Alaska by mid-century The U.S. Geological Survey (USGS) recently published nine new studies polar bears, focusing on how global warming and the melting of their sea ice habitat will impact them in coming years. The results are shocking: The studies predict that almost two-thirds of the world's 19 polar bear populations will be extinct by mid-century and that three more populations of polar bears will probably be extinct within 75 years. The studies indicate that loss of polar bear habitat will be most severe in the Chukchi Sea and Barents Sea. In only forty or fifty years, polar bears will likely be eliminated from Alaska and the southern end of their range, where sea ice is moving farther from land. Polar bears are only predicted to hang on in the Canadian Arctic islands and some regions along the northern coast of Greenland.
Photo: COREL 
Learn more about global warming in the ArcticWhat’s at stake for the Polar Bear?
Arctic ice loss from 1979-2005
Image: NASA Polar Bear Politics
Read the Fish and Wildlife Service's fact sheet on polar bears (pdf).
