October is a critical month for grizzly bears in Yellowstone National Park. As winter approaches, these powerful predators enter the final stages of hyperphagia, a period of increased feeding that allows them to accumulate the fat reserves needed for hibernation. Across the Greater Yellowstone Ecosystem, grizzlies seek high-calorie foods including whitebark pine nuts, roots, berries, and animal carcasses. Their feeding behavior, movement patterns, and habitat use reflect the changing conditions of autumn. For wildlife photographers, October offers the opportunity to capture grizzly bears against golden grasslands, dark forests, and the first snow-covered ridgelines of the season. In this edition of The Wild in Yellowstone, we explore grizzly bear hyperphagia, where to look for autumn activity, and photography techniques for documenting these remarkable animals responsibly.