Scientists who studied and tracked the bears determined that they survive despite having limited access to sea ice — something that is critical for polar bears — and instead use the freshwater ice supplied by Greenland’s ice sheet.
“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,” said lead study author Kristin Laidre, a polar research scientist at the University of Washington’s Applied Physics Laboratory, in a statement.
“We knew there were some bears in the area from historical records and Indigenous knowledge. We just didn’t know how special they were.”
An icy necessity
Traveling far, the 19 known polar bear populations rely on sea ice to hunt their prey, like ringed seals, and sit near breathing holes to capture their prey. The calories provided by seals can help them store energy for months when food and sea ice is more scarce.
Global warming is causing sea ice to rapidly melt and disappear as the Arctic warms more than twice as fast as the rest of the planet. When sea ice disappears, polar bears must move on land, which affords them fewer opportunities for food.
Meanwhile, the southeast Greenland polar bears tend to stick close to home, so they have adapted to their environment in a unique way. Although they are isolated due to the Greenland ice sheet, mountains, open water and fast-flowing coastal currents, the polar bears have access to freshwater ice and some limited access to sea ice, which helps them catch seals.
The bears can use sea ice between February and late May. For the rest of the year, they hunt seals using the freshwater ice as it breaks away from the ice sheet.
“Polar bears are threatened by sea ice loss due to climate change. This new population gives us some insight into how the species might persist into the future,” said Laidre, also a University of Washington associate professor of aquatic and fishery sciences.
“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.”
The environment of southeast Greenland is a unique, small-scale climate refuge where the bears can survive, and similar habitats can be found along Greenland’s coast and the Norwegian island of Svalbard.
“These types of glaciers do exist in other places in the Arctic, but the combination of the fjord shapes, the high production of glacier ice and the very big reservoir of ice that is available from the Greenland Ice Sheet is what currently provides a steady supply of glacier ice,” said study coauthor Twila Moon, deputy lead scientist at the US National Snow and Ice Data Center in Boulder, Colorado, in a statement.
“In a sense, these bears provide a glimpse into how Greenland’s bears may fare under future climate scenarios,” Laidre said. “The sea ice conditions in Southeast Greenland today resemble what’s predicted for Northeast Greenland by late this century.”
The new study is comprised of 30 years of historical data from Greenland’s east coast and seven years of new data from the…