Little Bighorn River Bighorns have rattlesnakes because they also support a habitat for small mammals, like a mouse and chipmunk population, which are the prey of rattlesnakes. With the restoration of the black bear population in the Bighorn Mountains, there has been a resurgence of black bear living along the stream as it flows out of Montana, extending down the Little Bighorn Valley in Montana. Ranchers between the mouth of the canyon (at about the Wyoming Montana line) down to Wyola often report black bear groups living in the timber along the river, and travelers on the Montana portion of the Little Horn
Little Bighorn River turn, would wet moccasins and leggings of Indian people, and the bellies and legs of horses, and cause them to look greasy. On the main stream, the name Greasy Grass slowly gave way to the name Little Bighorn. For one major tributary of the Little Bighorn, the (presently named) Lodge Grass Creek retained the name "Greasy Grass Creek", but as Joe Medicine Crow explained in the 2012 video, this name morphed from "Greasy Grass" to "Lodge Grass" due to the error of an interpreter since the Crow word for "greasy" is Tah-shay, and the Crow word for "lodge" is Ah-shay.