Ashore on Svalbard, a male polar bear investigates a whale's backbone. Fat reserves from hunting ringed and bearded seals, and sometimes walruses, must carry bears through lean summers. Photo (c) Florian Schulz
Their arctic habitat in full meltdown mode, polar bears have become the real bad news bears. Reports of drowned, starving and stranded bears, even cannibalism have become commonplace, and dire forecasts for their future just keep coming. Susan McGrath details the way thinning sea ice is making life harder for these iconic mammals in her article, “On Thin Ice.” Read on to preview an excerpt from story, which will be featured in the July issue of the National Geographic magazine, available on newsstands June 28.
The world didn’t know it yet, but during the summer in the Arctic Ocean, sea ice had been melting earlier and faster, and the winter freeze had been coming later. In the three decades since 1979 the extent of summer ice has declined by about 30 percent. The lengthening period of summer melt threatens to undermine the whole Arctic food web, atop of which stand polar bears……
The sea ice above the shallow continental shelves provides the richest sustenance for polar bears, but recently the ice has been retreating far from those areas, reducing the summer habitat bears need most to survive. Whether a polar bear lives in Hudson Bay or the Beaufort or Barents Seas, it faces the same problem. Sea ice on which to hunt is available for progressively shorter periods, forcing bears to fast for longer periods. And because thinner sea ice is more easily shifted by winds and currents, bears may be swept into strange territory, forcing them to make longer, more arduous swims in open water to find favorable sea ice or to get to land.
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Defenders is exploring measures to keep both polar bears and Alaskans safe as the loss of sea-ice forces the marine mammals farther inland. Read our report, Sea Bear Under Siege, to see an extensive list of actions that should be undertaken to assist these Arctic marine animals.
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