The American West is defined by its great mountain ranges and the Rocky Mountains that span much of the continent, stretching 3,000 miles north to south. Great rivers begin as a trickle of snowmelt, watersheds that flow to the Pacific and Atlantic oceans. Without these mountains, there would be no western rivers, no sagebrush, no shortgrass prairie. Relatively few creatures can survive harsh winters in these mountains, but white-tailed ptarmigan adapt through seasonal camouflage and a winter diet heavy on willow buds, while ungulates - mule deer, elk, bighorn sheep, and moose seek lower elevations. Pika and marmots slumber through winter, white-crowned sparrows and brown-capped rosy finch migrate after spending breeding season above timberline. Culturally, we view these mountains as wilderness and protect them as wilderness islands; but the Rocky Mountain story is in how mountains are interconnected to sage and prairie, and how watersheds provide life far from where rivers begin.