The eastern diamondback rattlesnake, Crotalus adamanteus, is a large, venomous snake native to the southeastern United States. Eastern diamondbacks are among the largest snakes in North America.
The eastern diamondback is a pit viper averaging 3 to 7 feet in length, with 8 feet being the record. It is a bulky snake with colors from brown to nearly black. It gets its name from the dark diamond pattern running down its back. Like all pit vipers it has a large, triangular shaped head. A dark band extends down from the eye, with lighter borders on each side. The tail is often darker than the rest of the body. There is no color dimorphism between sex and young snakes are similar in appearance to adults.
Eastern diamondbacks are found from southern North Carolina to eastern Louisiana, and are common throughout Florida. They prefer habitats such as dry forests and palmetto flats. Eastern diamondbacks may occupy wetland edges and will swim if necessary, but they largely avoid wet habitats.
These snakes are solitary and secretive. Behavior varies between individuals; some snakes give ample warning upon approach while others are silent. They often back away from confrontation but will strike if heavily provoked. Eastern diamondbacks feed largely on mammals and are of great value to humans in keeping populations of nuisance mammals, such as rabbits and rodents, at manageable levels.