Meltdown: Arctic wildlife is on the brink of catastrophe
Posted: Sat Nov 13, 2004 3:13 pm
Polar bears could be decades from extinction, a survey into global warming has found. Steve Connor reports on the crisis that threatens the polar ice-cap
Polar bears, the biggest land carnivores on Earth, face extinction this century if the Arctic continues to melt at its present rate, a study into global warming has found. The sea ice around the North Pole on which the bears depend for hunting is shrinking so swiftly it could disappear during the summer months by the end of the century, the Arctic Climate Impact Assessment (ICIA) says.
Scientists in the study believe the survival of the estimated 22,000 polar bears in the region is hanging by a slender thread as they suffer the double whammy of chemical pollution and dwindling feeding territories. Polar bears traditionally hunt on floating sea ice for seals and other quarry. But the ice has retreated significantly during summer, so the carnivores are having to swim further from one floe to another in search of quarry.
As a result of this extra effort, many bears are failing to build up the necessary fat reserves during the important hunting period of spring and early summer to take them through the bitterly cold winter months when females nurse their young. The sea ice in the Hudson Bay area of Canada, for instance, breaks up about two and a half weeks earlier than it did 30 years ago, Ian Stirling of the Canadian Wildlife Service said.
The rapid and unprecedented shrinkage of the ice, and the extra burden it places on the animals, has resulted in the polar bears here weighing, on average, 55lb less than they did in the 1970s. And the bears have long become more than a nuisance in Churchill, Manitoba, on the shore of Hudson Bay. They are frequently tranquilised and flown back north.
Scientists at the World Wildlife Fund said that, if that continues, many of the polar bears in the Hudson Bay area will be so thin within the next 10 years that they could become infertile. Lara Hansen, chief scientist at the WWF, said: "If the population stops reproducing, that's the end of it."
Separate studies have already shown that toxic pollutants are building up in the fat of polar bears in a way that could affect their ability to reproduce. WWF scientists say these toxins are affecting the bears' immunity to infections.
The ACIA is the product of four years' work by more than 250 scientists from Britain, the United States and many other industrialised countries. Its 139-page report, presented to a scientific conference this week in Reykjavik, found climate change is affecting the Arctic more than many other regions. For instance, scientists estimate that the polar region is warming at up to 10 times the rate of the world as a whole.
In Alaska, western Canada and eastern Russia, average winter temperatures have risen as much as 3C or 4C in the past 50 years, and they are projected to increase by a further 7C, or 13C, over the next 100 years.
More: http://news.independent.co.uk/world/env ... ory=581579
Polar bears, the biggest land carnivores on Earth, face extinction this century if the Arctic continues to melt at its present rate, a study into global warming has found. The sea ice around the North Pole on which the bears depend for hunting is shrinking so swiftly it could disappear during the summer months by the end of the century, the Arctic Climate Impact Assessment (ICIA) says.
Scientists in the study believe the survival of the estimated 22,000 polar bears in the region is hanging by a slender thread as they suffer the double whammy of chemical pollution and dwindling feeding territories. Polar bears traditionally hunt on floating sea ice for seals and other quarry. But the ice has retreated significantly during summer, so the carnivores are having to swim further from one floe to another in search of quarry.
As a result of this extra effort, many bears are failing to build up the necessary fat reserves during the important hunting period of spring and early summer to take them through the bitterly cold winter months when females nurse their young. The sea ice in the Hudson Bay area of Canada, for instance, breaks up about two and a half weeks earlier than it did 30 years ago, Ian Stirling of the Canadian Wildlife Service said.
The rapid and unprecedented shrinkage of the ice, and the extra burden it places on the animals, has resulted in the polar bears here weighing, on average, 55lb less than they did in the 1970s. And the bears have long become more than a nuisance in Churchill, Manitoba, on the shore of Hudson Bay. They are frequently tranquilised and flown back north.
Scientists at the World Wildlife Fund said that, if that continues, many of the polar bears in the Hudson Bay area will be so thin within the next 10 years that they could become infertile. Lara Hansen, chief scientist at the WWF, said: "If the population stops reproducing, that's the end of it."
Separate studies have already shown that toxic pollutants are building up in the fat of polar bears in a way that could affect their ability to reproduce. WWF scientists say these toxins are affecting the bears' immunity to infections.
The ACIA is the product of four years' work by more than 250 scientists from Britain, the United States and many other industrialised countries. Its 139-page report, presented to a scientific conference this week in Reykjavik, found climate change is affecting the Arctic more than many other regions. For instance, scientists estimate that the polar region is warming at up to 10 times the rate of the world as a whole.
In Alaska, western Canada and eastern Russia, average winter temperatures have risen as much as 3C or 4C in the past 50 years, and they are projected to increase by a further 7C, or 13C, over the next 100 years.
More: http://news.independent.co.uk/world/env ... ory=581579