Copperhead snakes have a distinctive hourglass-shaped pattern.
Credit: Matt Jeppson | Shutterstock
Copperhead snakes are one of the more commonly seen North American snakes — and also the most likely to bite. Though they are poisonous, their bites are rarely fatal for humans.
These snakes get their name, fittingly, from their copper-red heads. Some other snakes are referred to as copperheads, which is a common (non-scientific name) name. Water moccasins (cottonmouths), radiated rat snakes, Australian copperheads, and sharp-nosed pit vipers are all sometimes called copperheads, but they are different species from the North American copperhead (Agkistrodon contortrix).
Copperheads are pit vipers, like rattlesnakes and water moccasins. Pit vipers have heat-sensing pits on their faces, between their eyes and nostrils, which are able to detect minute differences in temperatures so that they can accurately strike the source of heat, which is often potential prey.
Copperheads are fairly large snakes, averaging between 2 and 3 feet (61 to 91 centimeters) in length, with females being longer than males; however, males possess proportionally longer tails. In addition to their unadorned copper-hued head, these snakes have reddish-tan bodies with a banded pattern. Darker cross-bands narrow in the middle, like hourglasses, and run down the body. Several other nonvenomous species of snakes have similar coloring, and are frequently confused for copperheads. Copperheads, however, are the only kind of snakes with hourglass-shaped markings.
Copperheads have muscular, thick bodies and keeled (ridged) scales. Their heads are large and triangular, and they have distinct necks. Their pupils are vertical, like cat’s eyes.
Young copperheads are more grayish in color than adults and possess yellow tails that they flick as bait for prey. This coloring fades as they age.
Copperheads reside as far south as the Florida Panhandle, as far north as Massachusetts, and as far west as Nebraska. There are five subspecies distributed according to geographic range: the northern, northwestern, southern, and two southwestern subspecies. The northern copperhead has by far the largest range, from Alabama to Massachusetts and Illinois.
Copperheads are happy in a wide variety of environments. They like rocky, wooded areas, mountains, thickets near streams, desert oases, canyons and other natural environments. They also thrive in wood and sawdust piles, abandoned farm buildings, junkyards and old construction areas.
Copperheads are semi-social snakes. While they usually hunt alone, they hibernate in communal dens shared with other copperheads and different species, such as rat snakes and rattlesnakes. They often return to the same den every year. They also can be seen near one another while basking in the sun, drinking, eating and courting.
Copperheads are usually out and about during the day in the spring and fall, but during the summer they become nocturnal. They especially like being out on humid, warm nights after rain. While they usually stay on the ground, copperheads will sometimes climb into low bushes or trees in search of prey or to bask in the sun. Sometimes, they even voluntarily go swimming.
It is hypothesized that copperheads migrate late in the spring to their summer feeding area, then return home in early fall.
Copperheads love to eat mice and other small rodents, and play an important part in keeping the rodent population regulated. They also enjoy small birds, lizards, amphibians, small snakes, and insects —especially cicadas. Copperheads use their heat-sensing pits to find prey. When attacking large prey, copperheads bite the victim, and then release it. They let the venom work, and then track down the prey once it has died. They usually hold smaller prey in their mouths until it dies. Copperheads eat their food whole, using their flexibly hinged jaws to swallow it. Adult copperheads may only eat 10 or 12 meals per year, depending on the size of their dinner.
Copperhead mating season is from February to May and from late August to October. Males fight with each other for the females, and those who lose rarely challenge again. A female may also fight prospective partners, and always reject males who back down from a fight with her.
After mating in the spring, females will give birth in the fall to between 1 and 14 live young in her hibernation den. After mating in the fall, the female will store sperm and defer fertilization for months, until she has finished hibernating. Copperheads are ovoviviparous, which means that eggs incubate inside the mother’s body. Babies are born live. While pregnant, some female copperheads will not eat because the fetuses take up too much space in her body. Baby copperheads are born with fangs and venom as potent as an adult’s.
Unlike most venomous snakes, copperheads give no warning signs and strike almost immediately if they feel threatened. Copperheads have the dubious distinction of having bitten the most people in the United States, but fortunately, their venom is not very potent. Children, the elderly and people with compromised immune systems may have strong reactions to the venom, however, and anyone who is bitten by a copperhead should seek medical attention.
Scientists have found that a chemical in copperhead venom may be helpful in stopping the growth of cancerous tumors.
- National Zoo
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- Ohio Public Library Information Network
- Virginia Herpetological Society
- University of Georgia