Posted on 05/17/2002 8:45:25 AM PDT by cogitator
Thin Polar Bears Called Sign of Global Warming
WASHINGTON, DC, May 16, 2002 (ENS) - Hungry polar bears are one of the early signs that global warming is impacting Arctic habitat, suggests a new study from World Wildlife Fund. The report reviews the threats faced by the world's 22,000 polar bears and highlights growing evidence that human induced climate change is the number one long term threat to the survival of the world's largest land based carnivores.
Global warming threatens to destroy critical polar bear habitat, charges the report, "Polar Bears at Risk." The burning of coal and other fuels emits carbon dioxide (CO2) and other gases that blanket the earth, trap in heat and cause global warming.
According to the Intergovernmental Panel on Climate Change (IPCC), climate change in the polar region is expected to be the greatest of anywhere on Earth.
"The WWF report shows that polar bears in Hudson Bay are being impacted by climate change," said Lynn Rosentrater, coauthor of the report and climate scientist at the World Wildlife Fund's (WWF) Arctic program. "The polar bear's basis for survival is being threatened by the reduction of the sea ice."
"Since the sea ice is melting earlier in the spring, polar bears move to land earlier without having developed as much fat reserves to survive the ice free season," Rosentrater explained. "They are skinny bears by the end of summer, which in the worst case can affect their ability to reproduce."
Increasing CO2 emissions have caused Arctic temperatures to rise by five degrees Celsius over the past 100 years, and the extent of sea ice has decreased by six percent over the past 20 years. By around 2050, scientists now predict a 60 percent loss of summer sea ice, which would more than double the summer ice free season from 60 to 150 days.
Sea ice is critical to polar bears' survival because it is the platform from where they hunt their primary prey - ringed seals and bearded seals. Diminishing ice cover and longer ice free periods limit the time the bears have on the ice to hunt and means that they have fewer fat resources to survive during the longer summer season.
Lower body weight also reduces female bears' ability to lactate, leading to fewer surviving cubs. Already, fewer than 44 percent of cubs now survive the ice free season.
As early as 1999, Canadian researchers noticed that polar bears in the Hudson Bay region were having trouble finding enough seals to eat due to the earlier breakup of sea ice. The scientists from the Canadian Wildlife Service found that weight for both male and female polar bears was declining, and female bears were having fewer cubs.
The impacts of global warming come on top of problems that polar bears already face from hunting, toxic pollution and oil development in the Arctic. The Arctic region is contaminated by pesticides and other chemicals carried by air and condensation from industrialized areas far to the south.
The pollutants enter the food chain, and animals at the top of the chain, such as polar bears, can carry tremendous body burdens of toxic chemicals. Research on polar bears has shown a link between high contaminant levels and reduced immune system function.
Due to the rapid pace of change in the Arctic, there is no time to lose in reducing emissions of greenhouse gases, WWF argues. The group says major reductions can be achieved by using existing technologies to increase the energy efficiency of homes, businesses and automobiles, and by using renewable energy sources instead of fossil fuels.
Bipartisan support has grown in Congress for a renewable portfolio standard that would ensure that 20 percent of U.S. energy comes from renewable energy by 2020. However, President George W. Bush has opposed the proposal.
World leaders will discuss a similar proposal at the World Summit for Sustainable Development in South Africa this summer. The WWF is calling on President Bush to support this initiative in Johannesburg.
"Arctic nations that are home to most of the world's polar bears should be leading the charge against global warming," said Jennifer Morgan, director of WWF's climate change program. "Instead, the United States - the world's largest global warming polluter - is essentially ignoring this problem. All eyes will be on President Bush at the upcoming World Summit on Sustainable Development in South Africa this August to test his commitment to sustainable energy solutions for climate change."
The WWF has created a new Web site: http://www.panda.org/polarbears with extensive information about polar bears and their Arctic domain. The site includes satellite tracking of two female bears, Louise and Gro, as they roam the ice pack in search of prey.
The United States isn't exactly an "Arctic" nation, sweets (parts of North Dakota and Maine excepted).
Any Canadians care to comment?
No, its a sign that they need more, preferably chubby, tree-huggers to visit.
I hadn't thought of that solution. Good plan.
One day Chicken Little was walking in the woods when -- KERPLUNK -- an acorn fell on her head
"Oh my goodness!" said Chicken Little. "The sky is falling! I must go and tell the king."
Well, the problem with the Churchill (Manitoba) polar bears has been known for a couple of years; I saw TV shows about it a couple of years ago. But the Hudson Bay polar bears are a subset of the entire polar bear population, so to extrapolate the condition of these bears to the whole population is certaintly stretching the data. They are, like most top predators, suffering from food-chain concentration of environmental contaminants, but I think other species (such as St. Lawrence belugas and Puget Sound orcas) are in worse shape.
(pause)
naaaaaaa........
Any chance they are adapting to the warmer weather we had this year and need less fat ?
Last January, a population of 27,000 bears was reported, along with a 66% error in counting: Higher Nunavut polar bear numbers lead to hopes of increased hunting trade
IQALUIT, Nunavut (CP) - A new survey has found 66 per cent more polar bears in an area of Nunavut than was previously estimated, raising hopes for more visits from American hunters. Nunavut's is estimated to have 16,000 bears - more than half the entire global population of 27,000.
This link sheds some light on that.
Quotes:
"Eighty per cent of the adult bears in the Churchill area have been tranquillized, handled, tagged, tattooed, weighed and measured, had blood drawn, teeth checked, their behaviour and life history recorded, many more than once."
...
"The scientists have found that for every week the ice breaks up earlier the bears come ashore 10 kilos lighter."
This article also notes that the Manitoba/Hudson Bay population is the best-studied polar bear population anywhere.
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