The Florida cottonmouth is found around fresh water. It is heavy bodied with a short tapering tail. It grows to a length of three feet, but can reach five feet in length. Its broad head is noticeably larger that its neck. The color pattern varies from olive-brown to black with or without crossbands.
Mature ones are dark gray-brown to black.
Other water snakes are frequently mistakenly killed as Florida cottonmouths. It is a forward fanged fish eater, and can strike from any position. It will often threaten by opening its mouth to reveal the whitish lining within. Thus, the name cottonmouth. The average litter is three to twelve young.