Back to Home Page
Back to Index

(For the week of June 8, 2009)
Watch out for Cottonmouths
by James L. Cummins

Summer is rapidly approaching, and so are the warm temperatures. Along with the increase in temperature is an increase in the activity of reptiles. Included among the many reptile species of Mississippi is the cottonmouth, or water moccasin as it is commonly called. It derives its name from the white inner-mouth which is commonly exposed when the snake is threatened.

The cottonmouth is a very heavy-bodied, large pit viper, usually 30 to 42 inches in length and is one of the most abundant snakes found in the South. Cottonmouths found in Mississippi are of the Eastern subspecies and the adults are usually a light brown to tawny-yellow color with light faces. However, adult cottonmouths found in the Delta of Mississippi are of the Western subspecies and are olive, dark brown or black in color.

Juvenile cottonmouths are generally lighter in color than the adults. Coloration is generally reddish crossbands on a pink or rusty color with yellow to greenish tails. These bright bands are often used to lure small animals. Due to the coloration and banding of juveniles, they are often mistaken for copperheads. As juveniles continue to age, they lose these characteristics and after 2 or 3 years acquire the coloration of adults.

Cottonmouths live in almost any type of wetland from brackish marshes of the Gulf Coast to streams, ponds, lakes, rivers and swamps of the rest of the state. Occasionally, these snakes are found on land away from any permanent water source.

During spring and fall, cottonmouths are very active during daylight hours, predominantly during early morning and late afternoon. During summer, when temperatures become extremely hot, they become nocturnal and move frequently under the cover of darkness, during cooler temperatures.

Breeding takes place in August and September and offspring are born about 3 months later. After breeding, cottonmouths begin to leave their aquatic habitat for adjacent upland areas where hibernation will take place. Usually by November, cottonmouths have totally disappeared from aquatic areas.

Cottonmouths are opportunistic feeders. Dead or diseased fish make up most of their diet, but these snakes will also feed on small mammals, birds, frogs and other species of snakes.

According to Terry L. Vandeventer, a professional herpetologist, contrary to popular belief, cottonmouths are not aggressive, but defensive. “In many instances cottonmouths will retreat at the approach of a human, but when an encounter cannot be avoided, it will defend its ground,” stated Vandeventer. “When a snake is encountered, leave it alone. Take two steps backward and go out of your way to avoid the snake.”

James L. Cummins is executive director of Wildlife Mississippi, a non-profit, conservation organization founded to conserve, restore and enhance fish, wildlife and plant resources throughout Mississippi.