Why it's called a cottonmouth. The cottonmouth probably has more common names than any other North American snake. A large adult crossing the Snake Road at night. The Shawnee cottonmouth is the subspecies known as the Western Cottonmouth, Agkistrodon piscivorus leucostoma . It can reach a length of five feet, although three foot specimens are more common.
Older specimens tend to have a reduced color pattern, and an overall dark color.
Young cottonmouths are boldly patterned, and are sometimes mistaken for copperheads. The pattern serves as camouflage, enabling the serpents to blend in with fallen leaves and vegetation. Camouflage on the forest floor. In the center of the photograph above is a juvenile cottonmouth. The snake was about a foot away from the author's boots when the photograph was taken.