Fat Bear Week: How Alaska’s brown bears nearly double in size

Every year around this time, the brown bears of Katmai National Park and Preserve in Alaska manage to double their weight in a few months. Thanks to the efforts of the park’s enterprising social media team since 2014, we now celebrate this festival of feasting as Fat Bear Week.

But how is it that the bears know when it’s time to bulk up? In late summer in Alaska, brown bears (Ursus arctos …