Agkistrodon piscivorus leucostoma

Common names: western cottonmouth,^[2] water moccasin, cottonmouth,^[3] more.

Agkistrodon piscivorus leucostoma is a venomous pitviper subspecies^[4] found in the south central United States.

Additional recommended knowledge

Weighing the right way

Safe Weighing Range Ensures Accurate Results

Essential Laboratory Skills Guide

Description

  This is the smallest of the three A. piscivorus subspecies, rarely growing beyond 42 inches in length. They have a broad, triangular shaped head, small eyes with vertical pupils, and heat sensing pits on either side of the nose.

Its color pattern is typically dark; either black, dark brown, or a dark olive green, with a muddy appearance. Sometimes muted banding is present. Juveniles have a more striking appearance, with distinctive light and dark banding and a bright yellow-green tail tip. As they age, the banding and color on the tail tip fade. They get their name from the white interior of their mouth, which can be seen if the snake is threatened. Often the main response to being cornered is for the snake to lift up its head and gape its mouth.

Common names

Western cottonmouth, water moccasin, cottonmouth, (black) moccasin, blunt-tail moccasin, (northern) cottenmouth moccasin, stump-tail (water) moccasin, viper, western cottonmouth moccasin.^[3]

Distribution & Habitat

A. p. leucostoma is found from the eastern half of Texas, across the southern states of Arkansas, Louisiana, Mississippi and Alabama, into Georgia, north to the western Tennessee, western Kentucky, southwestern corner of Indiana, southern Illinois, southern Missouri, southeast Kansas, and eastern Oklahoma.

Cottonmouths are rarely found far from a permanent water source, such as a slow moving stream, edge of a lake, pond, swamp, or even brackish tidal estuaries. Throughout much of their range, they are found in open flatwood pine forests or bald cypress swamps.

The type locality given is "western district of Tennessee." Schmidt (1953) proposed that this be emended to "10 miles northeast of Bolivar, Hardeman County, Tennessee."^[1]

Behavior & Diet

Cottonmouths have an undeserved reputation for being aggressive, but in actuality, they prefer to flee from a threat if given the opportunity. If cornered, they may gape their mouth, but will generally only strike as a last resort, or if harassed or physically provoked. In behavioral tests at the University of Georgia, it was found that only 13 out of 36 test specimens actually bit when provoked.^[1] Only 7% of snake bite cases in the state of Texas involve cottonmouths.

Another common myth about cottonmouths is that they "nest" in large groups. This is untrue. Cottonmouths are solitary creatures, and if there is more than one in an area, it is either breeding season or simply that the habitat is such that it can support several animals.

Frogs, fish, small mammals, other snakes, birds and even carrion make up the cottonmouth's diet. They generally will not pass up an easy meal, so even fish on stringers may be taken. In order to consume fish and frogs, they are quite able to bite under water.

Reproduction

Females reach sexual maturity at three years of age; males at two years. Mating occurs in the spring. They are ovoviviparous, giving birth to an average of six 6-10 inch young in the early fall. Average lifespan is approximately 10 years.

See also

• List of crotaline species and subspecies
• Crotalinae by common name
• Crotalinae by taxonomic synonyms
• Snakebite

References