Polar bears rely on sea ice to survive.
That's one reason images portraying a helpless polar bear standing on a small iceberg have become a potent symbol for the global environmental movement to combat the cause and effects of global climate change.
In a surprising study published Thursday in the academic journal Science, researchers announced the discovery of a population of polar bears in southeastern Greenland that have adapted to living in an environment with very little sea ice.
"This new population gives us some insight into how the species might persist into the future,” said polar scientist Kristin Laidre, one of the study's co-authors, according to an embargoed release shared with IE. “But we need to be careful about extrapolating our findings, because the glacier ice that makes it possible for Southeast Greenland bears to survive is not available in most of the Arctic," she said.
These polar bears have spent generations in isolation
These polar bears live in a rugged part of Greenland so far-flung that the researchers behind the new study had to take a four-hour commute (by helicopter) just to access the bear's territory. The region's unpredictable weather and rough terrain made travel even more difficult for the researchers and — presumably — for the bears themselves, whose ancestors have been completely separated from other populations for centuries.
“They are the most genetically isolated population of polar bears anywhere on the planet,” said biologist Beth Shapiro, another co-author. “We know that this population has been living separately from other polar bear populations for at least several hundred years, and that their population size throughout this time has remained small.”
Get more updates on this story and more with The Blueprint, our daily newsletter: Sign up here for free.
The researchers already had some indication from historical records and indigenous knowledge that bears lived in the region, which is isolated from the rest of the island by jagged mountains, vast ice sheets, and treacherous bodies of water. But they didn't realize how distinctive the population was. “We wanted to survey this region because we didn’t know much about the polar bears in Southeast Greenland, but we never expected to find a new subpopulation living there," Laird said.
Can polar bears survive global climate change?
These polar bears are different from other members of other populations in a few interesting ways that might offer hints at how the species could manage to survive life in a warmer world. “The sea ice conditions in Southeast Greenland today resemble what’s predicted for Northeast Greenland by late this century," Laird said.
GPS monitoring reveals one key difference: these bears stay close to home. That's distinctly different from most polar bears, which feed themselves and their young by traversing sea ice for long distances in search of tasty seals. The bears in the newly discovered population spend most of the year hunting seals that congregate on freshwater ice, not sea ice.
This new population offers insight into how wild polar bears could survive in a warmer world, but the findings don't mean that polar bears are good to go. “If you’re concerned about preserving the species, then yes, our findings are hopeful — I think they show us how some polar bears might persist under climate change,” said Laidre. But this kind of habitat won't be able to support the current population of polar bears. "There’s just not enough of it. We still expect to see large declines in polar bears across the Arctic under climate change," Laidre said.