"In fact, the polar bears located in the region that Unger lived in are one of 8 subpopulations in decline, according to a comprehensive review conducted in 2009. The following graphic illustrates the 19 distinct subpopulations of polar bears, only one of which is thought to be increasing:
While polar bear populations have increased since the 1970s thanks to conservation efforts, climate change could threaten "the survival of polar bears as a species," according to a 2004 assessment. And the U.S. Geological Survey projected in 2007 that changes in Arctic ice conditions could result in "loss of approximately 2/3 of the world's current polar bear population by the mid 21st century."
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