The Blackfoot River and its surrounding bioregion form a Blackfoot watershed of 1.5 million acres, with headwaters near Roger's Pass atop the Continental Divide. This vast area provides prime habitat for fish including westslope cutthroat and bull trout, large mammals such as grizzly bear, wolverine, and lynx, game birds including the rare Columbian sharp-tailed grouse, and two hundred species of migratory birds such as the greater sandhill crane and long-billed curlew. Its wetlands are key to the health and diversity of the ecosystem, while more than six hundred species of plants thrive alongside spring creeks, prairie potholes, and glacial lakes, including twenty-six rare plant species such as mosses, lichens, spotted coralroot, and creeping snowberry. When Meriwether Lewis traveled on the Road to the Buffalo near here in 1806, he recorded native vegetation including common juniper, rocky mountain iris, twin berry honeysuckle, silvery lupine, and arrowleaf balsamroot, and he and his men saw beaver and many beaver dams, plentiful deer, and a moose that frightened Lewis's dog Seaman. Moose, elk, and deer still frequently visit Aspen Grove Campground today.