(Web Desk) - Polar bears’ exceptional capacity to transform seal fat into insulation and energy has allowed these massive creatures to thrive in the Arctic for millenia.
But that capacity rests on a crucial — and increasingly imperiled — resource: sea ice. Frozen area is already down by 40pc since 1979, and melting is likely speeding up — last summer was the warmest on record in the Arctic.
Scientists suspect that the first ice-free Arctic summer could come as soon as the 2030s.
Without sea ice, polar bears can’t reach the seals on which they depend.
As climate change transforms the Arctic faster than most other places on Earth, this vital resource is melting from underneath polar bears’ feet.
Some regions support only half the polar bears they used to, and all are facing an uncertain future.
Perhaps more than any other species, polar bears symbolize climate change’s existential threat to biodiversity, raising questions about the long-term prospects of this icon of winter in a warmer world.
“Overall, it’s a pretty simple story,” said biologist Andrew Derocher.
As the globe heats up, sea ice will melt, and polar bears will starve.
But that simple story also belies complexities, he explains.
For now, there are about 26,000 polar bears, substantial numbers compared with some other endangered species. While some populations are declining, others are stable, or even growing, as warming opens up areas once too cold for the bears.
If we don’t rein in emissions, polar bears could be nothing more than a distant memory for future generations of humans. But that outcome isn’t set in stone.
“Our best analyses indicate that we will still have polar bears at the end of this century,” said Derocher.
“But it’s quite likely that their overall range will be quite reduced, and many populations will disappear.”
For now, there are about 26,000 polar bears, substantial numbers compared with some other endangered species. While some populations are declining, others are stable, or even growing, as warming opens up areas once too cold for the bears.
If we don’t rein in emissions, polar bears could be nothing more than a distant memory for future generations of humans. But that outcome isn’t set in stone.
“Our best analyses indicate that we will still have polar bears at the end of this century,” said Derocher. “But it’s quite likely that their overall range will be quite reduced, and many populations will disappear.”