Adult brown bear (Ursus arctos) foraging for salmon at the Brooks River, Katmai National Park, Alaska, United States of America

Adult brown bear (Ursus arctos) scratching its back on a tree at the Brooks River, Katmai National Park, Alaska, United States of America

Adult brown bears (Ursus arctos) foraging for salmon at the Brooks River, Katmai National Park, Alaska, United States of America

Adult brown bear sow (Ursus arctos) watching human activities at the Brooks River, Katmai National Park, Alaska, United States of America

Adult brown bear (Ursus arctos) feeding on humpback whale carcass in Glacier Bay National Park, Alaska, United States of America

Adult American black bear (Ursus americanus) near Mendenhall Glacier, Southeast Alaska, United States of America, North America

Adult grizzly bear (Ursus arctos) mother with cubs in Denali National Park, Alaska, United States of America

A curious young polar bear (Ursus maritimus) approaches the National Geographic Explorer in the Svalbard Archipelago, Norway, Arctic, Europe