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Cottonmouth Agkistrodon piscivorus


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Cottonmouth, Florida subspecies, young
credit: Ltshears

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Alternate name: Water Moccasin

Family: Viperidae, Pit Vipers view all from this family

Description Thick, heavy body. Brown, olive to grayish/black. Flat-topped head. Vertical pupils on eyes. Juveniles have a strong pattern. Keeled scales in rows of 25.

Dimensions 50.8-189.2cm. (20-74 1/2")

Warning Do not disturb or attempt to handle! The Cottonmouth's bite is far more serious than that of the Copperhead and can be fatal. When annoyed, the Cottonmouth tends to stand its ground and may gape repeatedly at an intruder, exposing the light "cotton" lining of its mouth. Cottonmouths, Copperheads, and rattlesnakes belong to a group of snakes known as pit vipers. These dangerous snakes have a heat-sensitive sensory organ on each side of the head that enables them to locate warm-blooded prey and strike accurately, even in the dark. The curved, hollow fangs are normally folded back along the jaw. When a pit viper strikes, the fangs rapidly swing forward and fill with venom as the mouth opens. The venom is a complex mixture of proteins that acts primarily on a victim's blood tissue. If you hear a rattlesnake shaking its rattle, back away. The snake is issuing a warning, and if the warning is ignored it may bite. There are many factors (temperature being the most important) that determine how a snake will react when confronted by a human. Venomous snakes should always be observed from a safe distance. Pit vipers are never safe to handle. Even dead ones can retain some neurological reflexes, and "road kills" have been known to bite. How to avoid and treat snakebites

Subspecies Eastern - Undefined cheek stripe. Virginia, North & South Carolina, Georiga to Alabama.
Florida - Distinct cheek stripe. Alabama, Georgia and Florida.
Western - no markings. Kentucky, Tennessee, Alabama, Missouri, Oklahoma, Texas.

Breeding Live young. Breeds Spring through Fall. 1-5 young. 18-33cm (7-13") long when born. Breeds on alternate years, mature at 3 years.

Habitat Swamps, lakes, rivers and canals. Also mountain streams.

Range Virginia to Florida Keys. Missouri, Oklahoma, Texas.

Discussion Aggression has been exaggerated but breeding males are vicious to any intruders. When it swims head is out of water. Active at night but often seen during the day. Fish, frogs, small snakes and birds form main diet.