cottonmouth

[From the white interior of its mouth.]

Agkistrodon piscivorus

SUBFAMILY

Crotalinae

TAXONOMY

Agkistrodon piscivorus Lacépède 1789 Carolina, later restricted to the vicinity of Charleston, South Carolina. Three subspecies are recognized.

OTHER COMMON NAMES

English: Water moccasin; French: Mocassin d'eau; German: Wassermokassinschlange, Wassermokassinotter.

PHYSICAL CHARACTERISTICS

The cottonmouth is a large, robust snake, occasionally exceeding 5.9 ft (1.8 m) in length and 10 lb (4.6 kg) in weight. One well-fed captive specimen reached a weight of about 23 lb (10.4 kg). In older adults, the dorsum typically is a uniform dark brown, black, or olive. Younger specimens have a lighter ground color with dark brown or reddish brown bands. Juveniles have a bright yellow or greenish tail tip. The loreal scale is absent (fused to the upper preocular scale). For this species, 23–27 (25 in most individuals) midbody scale rows have been recorded, along with 6–9 (8 in most individuals) supralabial scales, 128–145 ventral scales, and 36–53 subcaudal scales.

DISTRIBUTION

The cottonmouth inhabits the southeastern United States from southeastern Virginia south to Florida and west to central Texas and Oklahoma.

HABITAT

This snake inhabits swamps, streams, rivers, ponds, lakes, coastal marshes, rice fields, and several offshore islands. Occasionally it is found away from water.

BEHAVIOR

Cottonmouths are semiaquatic and can be found coiled in the open during the day or night. The name cottonmouth describes the bright white lining of the mouth, which is shown as a warning to creatures that approach too closely. It may be active during any month in the southern part of the range, but more northern populations hibernate. Most individuals are not aggressive, but numerous exceptions are known. This dangerous snake should not be handled.

FEEDING ECOLOGY AND DIET

The cottonmouth frequently forages by ambush, but it also may search actively for prey or feed on carrion. An interesting population on Seahorse Key, Florida, relies heavily on dead fish and young birds that drop from the nests of cormorants, herons, and egrets. Known prey include fish, amphibians, reptiles (among them, small alligators and turtles and even other cottonmouths), birds and their eggs, mammals, snails, insects, and crayfish. Juveniles attract prey by undulating their brightly colored tail tips.

REPRODUCTIVE BIOLOGY

This species gives live birth to 1–16 young, usually in August or September. Male combat has been documented.

CONSERVATION STATUS

The cottonmouth is still an abundant snake in many parts of its range, although local populations are threatened frequently or extirpated by habitat alteration (e.g., draining of wetlands, channeling of streams, and building of dams).

SIGNIFICANCE TO HUMANS

The cottonmouth is a dangerously venomous snake; bites can cause severe trauma and even death. In the past, this species has been killed systematically through organized snake hunts.

The noun has one meaning:

Meaning #1: venomous semiaquatic snake of swamps in southern United States
  Synonyms: water moccasin, cottonmouth moccasin, Agkistrodon piscivorus