
Polar bears already face shorter ice seasons - limiting prime hunting and breeding opportunities. Nineteen separate polar bear subpopulations live throughout the Arctic, spending their winters and springs roaming on sea ice and hunting. The bears have evolved mainly to eat seals, which provide necessary fats and nutrients in the harsh Arctic environment. Polar bears can't outswim their prey, so instead they perch on the ice as a platform and ambush seals at breathing holes or break through the ice to access their dens. The total number of ice-covered days declined at the rate of seven to 19 days per decade between 1979 and 2014. The decline was even greater in the Barents Sea and the Arctic basin. Sea ice concentration during the summer months — an important measure because summertime is when some subpopulations are forced to fast on land — also declined in all regions, by 1 percent to 9 percent per decade. Read more: <a href="http://go.nasa.gov/2cIZSSc" rel="nofollow">go.nasa.gov/2cIZSSc</a> Photo credit: Mario Hoppmann
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NASA ID
GSFC_20171208_Archive_e000220
Date Created
December 8, 2017
Center
GSFC
Media Type
image
Location
Greenbelt, MD
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960px