A cottonmouth is a venomous snake in the genus Agkistrodon, native to the Southeastern United States. Cottonmouths can be found from the Carolinas to Florida, and as far west as Texas. One species, Agkistrodon piscivorous, is particularly well known. As with many other venomous snakes, the cottonmouth has a reputation for being rather aggressive, but this is not, in fact, the case. These snakes would prefer to avoid people if possible in most cases, although some will stay in place and make threatening displays in an attempt to scare potential predators off. Only when directly approached or attacked will these snakes take more aggressive action.
The common name for these snakes is a reference to their white mouths, which become visible when cottonmouths gape to frighten predators or to prepare for a strike. The cottonmouth is also known as a “water moccasin,” thanks to the water-loving ways of A. piscivorous. These snakes can get quite long, growing up to six feet (two meters) in some cases with very thick, heavy bodies. Adult cottonmouths are brown, olive, or black, with cross-bars on their bodies which often blend in closely with the rest of their coloration. Juveniles are lighter in color, with more distinctive cross-bars and yellow tails.
These snakes have blunt snouts and clearly defined heads. They produce a hemotoxic form of venom which attacks blood cells and connective tissue when it enters the body, severely debilitating prey. A bite from a cottonmouth can be fatal if not promptly treated, and bites can still lead to amputation or loss of sensation due to venom damage.
Depending on the species, cottonmouths can be found in forests and wetlands. Many cottonmouths prefer moist areas, and these snakes are very good swimmers despite their heavy weight. Cottonmouths eat fish, other snakes, and small mammals, and they are not above resorting to carrion upon occasion. Most of these snakes hunt by ambushing their prey, although some will actively seek out prey, especially if they are hungry. Like other pit vipers, the cottonmouth has temperature-sensitive pits on its face which it can use to detect subtle temperature changes which may indicate a passing snack.
The cottonmouth is an ovoviviparous snake, which means that the females incubate eggs inside their own bodies, giving birth to one to six young. This type of reproduction carries some advantages for the cottonmouth and several other reptiles which also give birth to live young.
If you happen to see a cottonmouth in the wild, the best thing to do is to move away quietly. The snake may be as unhappy to see you as you are to see it, so as long as you move slowly and respectfully in the opposite direction, the snake will probably do the same. You should never approach a cottonmouth, as this may cause the animal to feel threatened, in which case it could strike.