SCIENTIFIC NAME:
Agkistrodon contortrix
STATUS:
Common statewide. Most frequently encountered venomous snake in Alabama. May be increasing in parts of Coastal Plain, especially where fire is suppressed. Lowest Conservation Concern.
DESCRIPTION:
Two of the five subspecies of copperhead snakes are found in Alabama. The northern copperhead (A. c. mokeson) and the southern copperhead (A .c. contortrix) are both stout-bodied snakes. The head is noticeably wider than the neck. The top of their head is a copper color, hence the name copperhead. Dark “hourglass cross bands” are common to both species. The body may be colored from a light brown to tan or pinkish in the southern copperhead. The northern copperhead usually has a darker and more reddish brown body color. Both belong to a group of snakes commonly called “pit vipers”. They get this name because of a pit, or tiny hole, located between the eye and nostril. These pits are heat seeking sensors that help the snake locate warm-blooded prey. Copperheads have elliptical pupils. Pit vipers have a set of well developed fangs capable of injecting venom.
DISTRIBUTION:
The northern copperhead is found from the Alabama-Tennessee boundary southward to the Tennessee River. It may be found in extreme northeastern Alabama below the Tennessee River. The southern copperhead is found along the Lower Coastal Plain. There is a broad zone of intergradation between the two subspecies.
HABITAT:
Copperheads are found in greatest numbers in forested areas that have numerous rocky bluffs and ravines. Along the Coastal Plain, the preferred habitat seems to be floodplains, swamp edges, and hilly terrain dominated by hardwoods. Copperheads can also be found along streams, hedge rows, and areas overgrown with kudzu. Abandoned farms and houses provide ideal habitat for copperheads throughout their range.
FEEDING HABITS:
Copperheads are predators near the top of their food chain. They usually wait in ambush for a meal. Their diet consists of small mammals (mice, shrews, moles, etc.), lizards, frogs, toads, insects (especially cicadas), small birds and salamanders. Survival can be maintained on just one meal every three weeks.
LIFE HISTORY AND ECOLOGY:
Snakes are “cold-blooded”, hence their need to hibernate during the winter months. A better term to describe “cold-blooded” is exothermic (use of external heat instead of metabolic heat for warmth). Copperheads remain active during the day when daylight temperatures are warm (spring and fall). However, during hot weather they are usually nocturnal (active at night).
Mating takes place shortly after emerging from hibernation in the spring. Copperheads can mate in the spring and fall. They have a live birth between July and August. The number of live young varies from as few as two to as many as 17. The average litter size is six to nine. Female copperheads may gather in areas known as “birthing rookeries” prior to giving birth. At birth, copperheads are eight to nine inches long and obtain a maximum length of approximately 53 inches. Adult lengths of 24 to 26 inches are more common. Young from both subspecies are born with a sulfur yellow tail tip. This yellow-tipped tail is wiggled to mimic a worm in order to attract prey.
Copperheads are not known as being an aggressive snake. They seldom strike unless stepped on or handled. Copperhead venom attacks the muscle and blood systems. Of all known venomous snakes in the United States, copperheads have the least toxic venom. Bites are painful but rarely fatal.
REFERENCES:
Jackson, Jeffery J. 1983. Snakes of the Southeastern United States. Publications Section, Georgia Extension Service.
Mount, Robert H. 1975. The reptiles and Amphibians of Alabama. Alabama Agricultural Experiment Station, Auburn.
Author:
Randy Liles, Supervising Wildlife Biologist, Alabama Division of Wildlife and Freshwater Fisheries