Eastern Cottonmouth

Cottonmouths or water moccasins are common residents of southeastern swamps; however, they can be found in almost any wetland within their range. This species is highly variable in coloration, but is usually plain brown or olive with darker blotches or bands. These snakes average 3 to 31/2 feet long and are very stout-bodied. Several species of harmless water snakes are often mistaken for cottonmouths and killed because people think they are venomous.

Cottonmouths feed on a variety of live animals including frogs, snakes, fish and even small mammals and birds. They use potent venom to kill their prey. They are commonly seen feeding on dead animals as well. Cottonmouths give birth to 4 to 12 young in the late summer. The young are boldly–patterned like copperheads and have a yellow-tipped tail.

Cottonmouths have a reputation for being vicious and aggressive. When confronted cottonmouths will often stand their ground and not retreat. This behavior is in stark contrast to many other species of snakes that will flee at the slightest provocation. When these snakes are alarmed they will pop their mouths open revealing a white interior, and vibrate their tails. Researchers at Savannah River Ecology Lab have found that these snakes will only bite for protection or food acquisition and will not chase and attack a person.

This information is provided as a public service by the Savannah River Ecology Laboratory Outreach Program.