Why undocumented polar bear persisting without sea-ice conditions



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Why undocumented polar bear persisting without sea-ice conditions

"Polar bears are susceptible to climate warming because of their dependence on sea ice, which is declining rapidly. We present the first evidence for a genetically distinct and functionally isolated group of polar bears in Southeast Greenland.

These bears occupy sea-ice conditions resembling those projected for the High Arctic in the late 21st century, with an annual ice-free period that is >100 days longer than the estimated fasting threshold for the species.

Whereas polar bears in most of the Arctic depend on annual sea ice to catch seals, Southeast Greenland bears have a year-round hunting platform in the form of freshwater glacial mélange. This suggests that marine-terminating glaciers, although of limited availability, may serve as previously unrecognized climate refugia.

Conservation of Southeast Greenland polar bears, which meet criteria for recognition as the world's 20th polar bear subpopulation, is necessary to preserve the genetic diversity and evolutionary potential of the species."

This was explained by the researchers of the study: Glacial ice supports a distinct and undocumented polar bear subpopulation persisting in late 21st-century sea-ice conditions, publishied on Science.

Why undocumented polar bear persisting without sea-ice conditions

In southeastern Greenland, a particular subpopulation of polar bears has been identified which, despite the scarce presence of sea ice, still manages to survive using small icebergs as platforms from which to hunt at sea.

The discovery seems to indicate a certain adaptability of these animals, at risk of extinction due to the progressive melting of the sea ice, on which they depend to obtain prey, due to global warming. The southeastern part is relatively less cold, but is essentially separated from the rest of the large island.

The polar bears living in the area are therefore quite isolated. These animals spend a good part of their existence on large sea ice shelves, waiting for some seals to resurface to catch their breath and hunt them, before returning to sink into the icy waters around the large ice shelves.