Discovered: Secret Population of Polar Bears

A distinct group of polar bears has been discovered in Greenland, which the website Live Science describes as a “secret population of polar bears found living in seemingly impossible habitat.”

The bears reside on steep slopes flanking fjords and hunt on the glacial ice that breaks up around the inlets. But these guys do not have the large platforms of ice that polar bears usually use to hunt.

Until now, scientists had identified 19 subpopulations of polar bears (Ursus maritimus) living in the Arctic Circle. Researchers examined one such group in Greenland and learned that it was in fact two groups. The scientists looked at 36 years of GPS tracking data and saw that bears from southeast Greenland did not roam beyond 64 degrees north latitude, while northeastern bears did not breach that line in the other direction. Genetic sampling confirmed that the populations are distinct and so the southeastern group will now be considered the world’s 20th subpopulation.

There are about 300 bears in the new group and genetics suggest they’ve been distinct from their northeastern neighbors for around 200 years. Interestingly, they are reckoned to be the most genetically diverse among all 20 populations in the Arctic.

On the one hand, the newly discovered population might suggest that glacier-ice hunting polar bears could adapt and survive in a world where sea ice is disappearing. On the other hand: “Glacier ice may help small numbers of polar bears survive for longer periods under climate warming, but it is not available for the vast majority of polar bears,” says lead researcher Kristin Laidre, a wildlife scientist at Polar Science Center at the University of Washington.

The IUCN lists polar bears as vulnerable to extinction, with about 36,000 individuals in the wild. Although they are the largest land predator in the world, U. maritimus are designated as marine mammals since they have an aquatic diet, mostly of seals. The new research appears in the journal Science.

Photo credit: Kristin Laidre / University of Washington