Adult brown bears (Ursus arctos) foraging for salmon 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 male polar bear (Ursus maritimus) on multi-year ice floes in Franz Josef Land, Russia, Arctic Ocean, Eurasia

Adult male polar bear (Ursus maritimus) on multi-year ice floes in Franz Josef Land, Russia, Arctic Ocean, Eurasia

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 tree, Brooks River, Katmai National Park, near Bristol Bay, Alaska, United States of America

View from Park Service platform where adult brown bears (Ursus arctos) forage for salmon, 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 (Ursus arctos) foraging for salmon in the Brooks River, Katmai National Park, Alaska, United States of America

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

A koala bear in the Barmah Forest near Echuca, Victoria, Australia, Pacific