Cottonmouths feed primarily on fish, frogs, mice, rats, and other small mammals. Often, cottonmouths are confused with water snakes, non-poisonous snakes who share the same habitats. These harmless water snakes are often killed out of fear and ignorance. Actually, cottonmouths are also often killed for the same reasons. Except for self defense or positive identification in the case of snakebite, it is best to leave all snakes alone.
Snakes help keep the environment in balance.
For instance, a shortage of snakes means an increase in the mice and rat population, which brings on epidemics of disease often fatal for humans. Also, picking up or attempting to kill a snake can be one sure way of being bitten. The cottonmouth moccasin, when threatened, coils and opens its mouth wide, displaying its fangs and exposing the white interior of its mouth and throat, thus the name cottonmouth. The adults are dark colored, almost black, and are heavy-bodied. Juveniles are brightly colored with reddish brown crossbands which contain many dark spots and speckles, and have a sulfur colored tail, which is held erect and wiggled like a caterpillar to attract prey within striking range.