Polar bear walking on pack ice with water pond

Polar bears survive in Greenland despite lack of sea ice – EcoWatch

Few animals represent the face of the Arctic Like it polar bears† The largest bears in the world, polar bears are excellent swimmers who spend more time in the sea than on land. Sea ice is the platform from which they hunt the seals necessary to obtain the necessary calories for survival.

Now scientists have found a subpopulation of polar bears in southeastern Greenland that have managed to survive by hunting using mostly freshwater ice flowing into the ocean from the continent’s glaciers. The isolated and genetically unique population could provide insight into the future of polar bears in a changing Arctic landscape.

The study of this rare subpopulation of polar bears, “Glacial ice supports a distinct and undocumented polar bear subpopulation that persists in late 21st century sea ice conditions,” was published in the journal Science

“We wanted to investigate this region because we didn’t know much about the polar bears in Southeast Greenland, but we never expected to find a new subpopulation there,” said polar scientist at the Applied Physics Laboratory at the University of Washington. Kristin Laidre, who was the lead author of the study, as the University of Washington (UW) reported. “We knew there were some bears in the area from historical records and native knowledge. We just didn’t know how special they were.”

For the study, the researchers collected data from the southeast coast of Greenland and combined it with three decades’ worth of data from the entire east coast of the continent. The area didn’t get much attention from researchers due to its rugged terrain and extreme conditions, but the new data shows the bears’ ability to survive mainly using ice from the glacier.

Polar bears are threatened by sea ice loss due to climate change† This new population gives us some insight into how the species might survive in the future,” Laidre said, as reported by UW. “But we have to be careful about extrapolating our findings, because the glacial ice that makes it possible for bears in Southeast Greenland for survival is unavailable in most of the Arctic.”

Professor and geneticist at the University of California, Santa Cruz, Beth Shapiro, who co-authored the study, said the Southeast Greenland population is the most genetically isolated in the world. According to Shapiro, the subpopulation has been living separately from other polar bear populations for at least hundreds of years. The subpopulation is more genetically different from its closest genetic neighbor than any other 19 documented populations of polar bears.

The bears have remained isolated because they are surrounded by mountains, water and the huge Greenland ice sheet. According to satellite data, they are also often “pets,” spending most of their time in local, protected fjords or neighboring fjords rather than traveling long distances across the sea ice like most polar bears do.

“I really think they can teach us something about where rare, small numbers of polar bears are in a… ice-free Arctic,” Laidre said, as reported by The Guardian.

The researchers took advantage of the knowledge of East Greenland subsistence hunters before and during the study, who provided them with samples to analyze.

Laidre said the habitat conditions of the polar bears, a subpopulation of southeastern Greenland, are similar to what the future terrain could be further north.

“In a sense, these bears give a glimpse of how Greenland bears will fare in future climate scenarios,” Laidre said, as UW reported. “Sea ice conditions in Southeast Greenland today resemble what was predicted for Northeast Greenland at the end of this century.”

From February to the end of May, polar bears in southeastern Greenland have access to sea ice, but for the rest of the year, the bears hunt for patches of freshwater ice erupted from the Greenland ice sheet.

This means that glaciers that consistently calve into the ocean could become a lifeline for polar bears as sea ice declines due to climate change.

“Even with rapid changes on the ice sheet, this area of ​​Greenland has the potential to continue producing glacial ice, with a coast that may [look] similar to today, for a long time,” said deputy chief scientist at the National Snow and Ice Data Center and study co-author Twila Moon, as reported by UW.

However, Laidre added that the unique glacier habitat was not large enough for a large population of polar bears.

“If you’re concerned about the conservation of the species, yes, our findings are hopeful — I think they show us how some polar bears can endure under climate change,” Laidre said, according to UW. “But I don’t think the glacier’s habitat will support huge numbers of polar bears. There just isn’t enough of it. We still expect a large decline in polar bear numbers in the Arctic under climate change.”

The polar bear subpopulation in Southeast Greenland is estimated by the researchers at a few hundred bears, with smaller-than-average adult females with fewer cubs, which could indicate difficulty finding mates due to the challenging landscape.

“The low body condition and low birth rate in southeastern Greenland suggest that this group of bears may already be on the brink of persistence,” said University of Alberta polar bear expert Professor Andrew Derocher, who was not involved in the study. , as The Guardian reported.

Recognition of southeastern Greenland’s polar bears as the world’s 20th unique population would be helpful in protecting them, a decision to be taken by the International Union for Conservation of Nature. Decisions regarding the management and protection of the species would be made by the Greenland government.

“Preserving the genetic diversity of polar bears is crucial for the future under climate change,” Laidre said, as reported by UW. “Officially recognizing these bears as a distinct population will be important for conservation and management.”

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