ナショナルジオグラフィックさんのインスタグラム写真 - (ナショナルジオグラフィックInstagram)「Photo by @joelsartore | Arctic National Wildlife Refuge, Alaska. Found only in the Arctic, polar bears are highly dependent on older stable pack ice, a platform from which they can rest, hunt, and mate. While polar bears are strong swimmers and have been seen in open waters as far as 200 miles from land, such activities require tremendous amounts of energy and can be fatal to younger bears. This makes the presence of ice patches extremely important for the survival of this species. To see how my photo shoot with a polar bear turned out, follow me @joelsartore. #polarbear #arctic #PhotoArk」4月6日 17時04分