What’s the difference between brown bears and grizzly bears?

All grizzly bears are brown bears, but not all brown bears are grizzlies. Brown bears (Ursus arctos) are the most widely distributed species of bears in the world; in many parts of the world regional brown bear populations are recognized as distinct subspecies. Generally, only brown bears in the interior portions of North America are referred to as grizzly bears. Bears living along the Pacific coast of Alaska and Canada and throughout Eurasia are referred to as brown bears.

North America’s brown bears enjoy a milder coastal climate and a diet of lush and varied vegetation and seasonally available rich, calorie-dense salmon that helps them grow larger and live in higher densities than their grizzly bear cousins in northern and interior lands.

The brown bears that have lived for thousands of years in an isolated population on Alaska’s Kodiak island are the largest brown bears on the continent, with mature males routinely tipping the scales at 1,000 pounds or more.