Glacial ice supports a distinct and undocumented polar bear subpopulation persisting in late 21st-century sea-ice conditions

  title={Glacial ice supports a distinct and undocumented polar bear subpopulation persisting in late 21st-century sea-ice conditions},
  author={Kristin L. Laidre and Megan Ann Supple and Erik W. Born and Eric V. Regehr and {\O}ystein Wiig and Fernando Ugarte and Jon Aars and Rune Dietz and Christian Sonne and Peter Hegelund and Carl Joakim Isaksen and Geir B Akse and Benjamin Cohen and Harry L. Stern and Twila A. Moon and Christopher Vollmers and Russell B. Corbett-Detig and David Paetkau and Beth Shapiro},
  pages={1333 - 1338}
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… 
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