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News 8 Sep
Polar bear population seen declining
By John Heilprin, Associated Press Writer
Yahoo News 7 Sep 07
Most polar bears could be lost by 2050: report
By Deborah Zabarenko, Environment Corresponden
Two-thirds of the world's polar bear population could be gone by midcentury if predictions of melting sea ice hold true, the U.S. Geological Survey reported on Friday.
The fate of polar bears could be even bleaker than that estimate, because sea ice in the Arctic might be vanishing faster than the available computer models predict, the geological survey said in a report aimed at determining whether the big white bear should be listed as a threatened species.
"There is a definite link between changes in the sea ice and the welfare of polar bears," said Steve Amstrup, who led the research team.
Arctic sea ice is already at an all-time low this year and is expected to retreat farther this month, according to the U.S. National Snow and Ice Data Center.
That means that polar bears -- some 16,000 of them -- will disappear by 2050 from parts of the Arctic where sea ice is melting most rapidly, along the north coasts of Alaska and Russia, researchers said in a telephone briefing.
Other polar bear populations could survive beyond that date but many of those could be gone by 2100, Amstrup said.
By century's end, the only polar bears left might live in the Canadian Arctic islands and along the west coast of Greenland.
"Projected changes in future sea ice conditions, if realized, will result in loss of approximately two-thirds of the world's current polar bear population by the mid 21st century," the report's executive summary said. "Because the observed trajectory of Arctic sea ice decline appears to be underestimated by currently available models, this assessment of future polar bear status may be conservative."
ARE POLAR BEARS 'THREATENED'?
In January, the U.S. Fish and Wildlife Service proposed listing the polar bear as a threatened species under the Endangered Species Act, noting polar bears depended on sea ice as a platform to hunt seals, their main prey.
The research released on Friday was sent to the Fish and Wildlife Service. A decision on the bears' status is expected in January.
Without enough sea ice, polar bears would be forced onto land, but they are inefficient hunters once they get out of the water and ice, the researchers said.
The bears' disappearance would probably take place as young cubs failed to survive to adulthood and females were unable to reproduce successfully.
The first polar bears probably first appeared about 40,000 to 50,000 years ago, and the species has not lived through a period as warm as the one predicted by the U.N. Intergovernmental Panel on Climate Change, the scientists said.
In a series of reports this year, the U.N. climate panel said with 90 percent probability that global climate change was occurring and that human activities contributed to it.
The emission of greenhouse gases -- including carbon dioxide from petroleum-fueled vehicles and coal-fired power plants -- is the prime human cause of this warming trend, the panel said.
Global warming was an important topic of discussions of the Asia Pacific Economic Cooperation forum this week in Australia and will be the subject of a special U.N. meeting later this month.
Yahoo News 8 Sep 07
Polar bear population seen declining
By John Heilprin, Associated Press Writer
Two-thirds of the world's polar bears will be killed off by 2050 — and the entire population gone from Alaska — because of thinning sea ice from global warming in the Arctic, government scientists forecast Friday.
Only in the northern Canadian Arctic islands and the west coast of Greenland are any of the world's 16,000 polar bears expected to survive through the end of the century, said the U.S. Geological Survey, which is the scientific arm of the Interior Department.
USGS projects that polar bears during the next half-century will disappear along the north coasts of Alaska and Russia and lose 42 percent of the Arctic range they need to live in during summer in the Polar Basin when they hunt and breed.
A polar bear's life usually lasts about 30 years.
"Projected changes in future sea ice conditions, if realized, will result in loss of approximately two-thirds of the world's current polar bear population by the mid 21st century," the report says.
Polar bears depend on sea ice as a platform for hunting seals, which is their primary food. They rarely catch seals on land or in open water.
Because the general decline of Arctic sea ice appears to be underestimated, scientists said their forecast of how much polar bear populations will shrink also may be on the low side.
"There is a definite link between changes in the sea ice and the welfare of polar bears," said USGS scientist Steven Amstrup, the lead author of the new studies. "As the sea ice goes, so goes the polar bear."
Amstrup said 84 percent of the scientific variables affecting the polar bear's fate was tied to changes in sea ice. As of this week, the extent of Arctic sea ice had fallen to 4.75 million square miles — or 250,000 square miles below the previous record low of 5.05 million square miles in September 2005, according to the National Snow and Ice Data Center.
Scientists do not hold out much hope that the buildup of carbon dioxide and other industrial gases blamed for heating the atmosphere like a greenhouse can be turned around in time to help the polar bears anytime soon.
Polar bears have walked the planet for at least 40,000 years.
"In spite of any mitigation of greenhouse gases, we are going to see the same amount of energy in the system for at least 20, 30, 40 years," Mark Myers, the USGS director, said. Greenland and Norway have the most polar bears, while a quarter of them live mainly in Alaska and travel to Canada and Russia.
The agency says their range will shrink to no longer include Alaska and other southern regions.
The findings of U.S. and Canadian scientists are based on six months of new studies, during which the health of three polar bear groups and their dependency on Arctic sea ice were examined using "new and traditional models," Myers said.
USGS issued nine separate reports on polar bears Friday. Those included projections for one group of polar bears in the Southern Beaufort Sea and two in Canada that are among 19 distinct subpopulations.
They were made public to help guide Interior Secretary Dirk Kempthorne's decision expected in January on his agency's proposal to add the polar bear to the government's endangered species list.
USGS declined to provide precise estimates of polar bear populations 50 years from now.
A separate organization, the World Conservation Union, based in Gland, Switzerland, has estimated the polar bear population in the Arctic now is about 20,000 to 25,000, put at risk by melting sea ice, pollution, hunting, development and tourism.
Last December, Kempthorne proposed designating polar bears as a "threatened" species deserving of federal protection under the Endangered Species Act, because of melting Arctic sea ice from global warming. That category is second to "endangered" on the government's list of species believed most likely to become extinct.
That action is in response to a lawsuit in 2005 by three environmental groups — the Center for Biological Diversity, Natural Resources Defense Council and Greenpeace — to force such a proposal from Interior's Fish and Wildlife Service, which oversees endangered species.
"This grim news about polar bears and sea ice decline is horrifying, but it is a call to action, not despair," said Kassie Siegel of the Arizona-based Center for Biological Diversity.
"The good news is that there is still time to save polar bears. Our hope lies in a rapid response, including both deep and immediate carbon dioxide reductions and a full-court press on other greenhouse pollutants such as methane."
The fate of polar bears has struck a public nerve.
Fish and Wildlife officials have received 600,000 public comments so far on the proposed listing, spokesman Chris Tollefson said.
On Friday, Rep. Edward Markey, D-Mass., urged the Bush administration to grant polar bears federal protection.
"This is becoming a tragic metaphor for the administration's voluntary approach to global warming," said Markey, chairman of the House Select Committee on Energy Independence and Global Warming.
"Instead of meeting the challenge, the Bush administration is happy to float along, waiting to see if the planet, and polar bears, will sink or swim."
Another member of the committee, Rep. Jay Inslee, D-Wash., said the loss of some of the magnificent creatures on earth may be the proverbial "canary in the coal mine" needed to prod both Congress and the Bush administration into action on climate change.
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