In a warming climate, this small, genetically different population of polar bears might be crucial to the species' survival.
Scientists discovered a previously unknown polar bear subpopulation in Southeast Greenland.
Polar bears hunt freshwater ice that flows into the ocean from Greenland's glaciers to supplement their restricted access to sea ice.
Studying this isolated population, which is genetically different and individually suited to its habitat, might provide insight into the species' future in the warming Arctic.
Polar bears' survival
They wanted to explore this area since researchers didn't understand much more about polar bears in Southeast Greenland, but really never anticipated uncovering a new subpopulation there, said lead author Kristin Laidre of the University of Washington's Applied Physics Laboratory, as per ScienceDaily.
From historical archives and Indigenous knowledge, scientists knew there were bears in the region, but they just didn't realize how unique they were.
The research, which was published in Science on June 17, combined seven years of fresh data obtained along Greenland's southeastern shore with 30 years of historical data from the island's whole east coast.
Because of its erratic weather, rugged mountains, and severe snowfall, the distant Southeast area has received little research.
According to co-author Beth Shapiro, a professor and geneticist at the University of California, Santa Cruz, and a Howard Hughes Medical Institute scientist, they are the most genetically isolated group of polar bears anywhere on the globe.
Experts know that this population has existed independently from other polar bear communities for at least several hundred years, and that its number has remained modest during that period.
The bears are boxed in on all sides by the jagged mountain peaks and vast Greenland Ice Sheet to the west, the wide water of the Denmark Strait to the east, and the fast-flowing East Greenland coastal current that poses a threat offshore, according to researchers.
Before beginning fieldwork, the team spent two years in East Greenland requesting input and gathering data from polar bear subsistence hunters.
Hunters contributed their knowledge and provided harvest samples for genetic research throughout the project.
Also Read: Consequences of Climate Change: Polar Bear Population Shrinking Due to Arctic Sea Ice Melt
Using Moderate Resolution Imaging Spectroradiometer
The team also used data from the National Snow and Ice Data Center (NSIDC) and the Moderate Resolution Imaging Spectroradiometer on NASA's Terra and Aqua satellites to characterize the conditions in the fjords and the offshore sea ice habitat.
They discovered that during two-thirds of the year, southeastern polar bears are shut off from sea ice.
The bears hunt from atop the shattered glacial ice floating at the front of glaciers, known as mélange, from late May until the sea ice returns in February.
According to co-author and NSIDC scientist Twila Moon, the marine-terminating glaciers in Southeast Greenland constitute a very unusual ecosystem.
These glaciers may be found in other parts of the Arctic, but the combination of fjord forms, high glacier ice production, and a large ice reservoir available from the Greenland Ice Sheet is what now ensures a consistent supply of glacier ice.
Southeast Greenland now resembles what scholars predict it will look like in the late 21st century as a result of climate change.
The adaptations made by southeastern polar bears may be indicative of how other polar bear populations may adapt to survive as global warming continues.
However, the scientists warned that glacier ice can only support a limited number of bears and that polar bear populations would certainly decline anyway.
Related article: Polar Bears Might Go Extinct by the End of the Century if Arctic Ice Continues to Melt