WASHINGTON • Polar bears face an existential threat from the rapid decline of Arctic sea ice, which they rely on as platforms to hunt seals.
But in a new study, scientists have identified an isolated subpopulation of polar bears in South-east Greenland that instead make use of freshwater ice pouring into the ocean from the region's glaciers, suggesting this particular habitat is less susceptible than others to climate change.
Their findings, described in the journal Science on Thursday, open up the tantalising possibility that at least some pockets of the species might be able to survive further into this century, when Arctic sea ice is expected to disappear completely during summer months.
"One of the big questions is where in the Arctic will polar bears be able to hang on, what we call 'persist'," first author Kristin Laidre, a polar scientist at the University of Washington and Greenland Institute of Natural Resources, told AFP.
"I think that bears in a place like this can teach us a lot about where those places might be," she said.
Dr Laidre and colleagues first spent two years interviewing Inuit subsistence hunters who provided input and ecological knowledge, including harvest samples for analysis. They then began their own field work, from 2015 to 2021, in a harsh region that was long lacking in being studied because of its unpredictable weather, heavy snowfall and jagged mountains.
Each year, the team would spend one month in springtime, staying in the nearest settlement Kuummiit, which is a two-hour helicopter ride from where the bears live. Fuel depots had to be staged along the route in advance down the coastline, creating a hopscotch-like commute to work.
The team tagged the bears with satellite tracking devices, and collected genetic samples by either capturing bears or firing biopsy darts into their rumps.
Thought to number a few hundred individuals, "they are the most genetically isolated population of polar bears anywhere on the planet", said co-author Beth Shapiro, a geneticist at the University of California, Santa Cruz, and investigator at the Howard Hughes Medical Institute, in a statement.
Unlike their cousins, the Southeast Greenland polar bears were found to be homebodies, seldom straying far to hunt.
To the west, there are an enormous set of mountains and the Greenland Ice Sheet, and to the east the open water of the Denmark Strait all the way to Iceland.
They also have to contend with a rapid current flowing southwards along the coast. "We see that when they get caught in this current they jump off the ice and they walk back home to their fjords," said Dr Laidre.
AGENCE FRANCE-PRESSE
