Northern Cottonmouth
Agkistrodon piscivorus • Order: Squamata, Suborder: Serpentes, Family: Viperidae, Subfamily: Crotalinae, Genus: Agkistrodon, Species: Agkistrodon piscivorus
Southeastern United States, ranging from southeastern Virginia south to the Florida Keys and west to eastern Texas and Oklahoma.
Look up Northern Cottonmouth in the Snake Encyclopedia →Venomous Status
Venomous; solenoglyphous (front-fanged with long, hollow, retractable fangs).
Danger Level
Extremely Dangerous; a bite is a medical emergency that can lead to severe tissue damage or death if untreated, though fatalities are rare with proper medical care.
Family
Order: Squamata, Suborder: Serpentes, Family: Viperidae, Subfamily: Crotalinae, Genus: Agkistrodon, Species: Agkistrodon piscivorus
Conservation
Least Concern (IUCN); however, populations face threats from habitat destruction and persecution by humans.
Physical Description
Thick, heavy body with a broad, triangular head. Dark brown, olive, or blackish coloration with crossbands that often fade in older adults. Distinctive dark 'mask' through the eye. Vertical (elliptical) pupils and heat-sensing pits.
Size & Dimensions
Typically 30 to 48 inches (76–122 cm). This specimen appears to be an adult of average size.
Habitat
Semi-aquatic; found in swamps, marshes, drainage ditches, and the edges of ponds, lakes, and slow-moving streams. Also found in terrestrial habitats adjacent to water.
Behavior & Temperament
Semi-aquatic and often slow-moving. Known for its defensive 'gaping' display, where it opens its mouth to reveal a white, cotton-like interior. Generally avoids conflict but will strike if provoked.
Diet & Feeding
Generalist carnivore; feeds on fish, frogs, turtles, birds, small mammals, and other snakes. Uses both ambush and active foraging; kills via venom.
Reproduction
Ovoviviparous (gives birth to live young). Litter size typically ranges from 1 to 20, usually occurring in late summer or early fall.
Venom Profile
Primarily hemotoxic and cytotoxic, causing tissue destruction, swelling, and blood-clotting issues.
Look-alikes
Commonly confused with harmless Nerodia (water snakes). Distinguishable by the Cottonmouth's blocky head, vertical pupils, and facial pits, whereas water snakes have round pupils and lack pits.
Conservation Status
Least Concern (IUCN); however, populations face threats from habitat destruction and persecution by humans.
Cultural Significance
Feared in American folklore; often unfairly characterized as overly aggressive. Plays a vital ecological role as an apex predator in wetland ecosystems.
Notable Features
The white lining of the mouth (the 'cotton' mouth) and the ability to swim with its entire body buoyed on top of the water surface.