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Northern Copperhead


Order: Squamata

Family: Viperidae

Genus/species: Agkistrodon contortrix


The average length of adult copperheads is 30 inches (76 cm). They have an unmarked copper-colored head, and reddish-brown, coppery bodies with chestnut brown crossbands that constrict towards the midline. Copperheads are thick-bodied and have keeled scales. There is a temperature-sensitive pit organ on each side of the head between the eye and the nostril. Young copperheads are seven to ten inches (18 to 25 cm) long and grayer in color than adults. They have a sulfur-yellow-tipped tail, but this color fades with age and is lost by age three or four. Copperheads are sexually dimorphic in size. Males have longer tails than females and females grow to greater lengths.

Copperheads are social snakes. They may hibernate in a communal den with other copperheads or other species of snakes including timber rattlesnakes and black rat snakes. They tend to return to the same den year after year. Copperheads can be found close to one another near denning, sunning, courting, mating, eating, and drinking sites. They are believed to migrate late in the spring to reach summer feeding territories and reverse this migration in early autumn.

Males are aggressive during the spring and autumn mating seasons. They try to overpower each other and even pin the other's body to the ground. This behavior is exhibited most often in front of females but this is not always the case. These interactions may include elevating their bodies, swaying side to side, hooking necks, and eventually intertwining their entire body lengths. Copperheads have been reported to climb into low bushes or trees after prey or to bask in the sun. They have also been seen voluntarily entering water and swimming on numerous occasions.

Distribution and Habitat

Overall, this species inhabits the Florida panhandle north to Massachusetts and west to Nebraska. Of the five different subspecies the northern copperhead (A. c. mokasen) has the largest range. It inhabits northern Georgia and Alabama north to Massachusetts and west to Illinois.

Copperheads prefer terrestrial to semi-aquatic habitats, which include rocky-forested hillsides and various wetlands. They have also been known to occupy abandoned and rotting wood or sawdust piles.

Diet in the Wild

The copperhead is a carnivore. Adults eat mostly mice but also small birds, lizards, small snakes, amphibians, and insects--especially cicadas. Copperheads have fangs that inject prey with a hemolytic venom (causes the breakdown of red blood cells) which subdues its prey, making it easy for the snake to swallow it. The copperhead seeks out its prey using its heat-sensitive pits to detect objects that are warmer than its environment. This also enables them to find nocturnal mammalian prey. Adult copperheads are primarily ambushers. When attacking large prey, the copperhead bites then releases immediately to allow the venom to take effect then later tracks its prey. Smaller prey is usually held in its mouth until it dies. They are most active April through late October, diurnal in the spring and fall, and nocturnal during the summer. When carrying young, some females will not eat at all because the embryos occupy so much of the body cavity.

Young copperheads eat mostly insects, especially caterpillars, and use their yellow-tipped tails as a worm-like lure to attract prey.

Zoo Diet

The copperhead is fed mice, rats, and chicks.


Both sexes reach sexual maturity at four years when they are about two feet in length. The breeding season is from February to May and from August to October. Males seek out sexually active females using their tongue to detect pheromones in the air. Once he has located a female, the male begins moving his head or rubbing his chin on the ground. Eventually, after courtship, the male aligns his body with hers. This courtship may last for an hour or more if the female does not respond. After being sufficiently stimulated, the female lifts and arches her tail and lowers the scale that covers her cloaca. Then the male arches his body and tail, everting one of his two hemipenes and mates with the female. Mating time varies; ranging from as long as 3.5 to 8.5 hours. The long mating time could correlate with the fact that females usually only mate with one male per year. During the mating period, males produce a pheromone that makes the female unattractive to other males, which pay little or no attention to mating or just mated females. Females also have little interest in mating after a long, successful first mating.

Females that breed in autumn store the sperm until after emerging from a hibernating site. The length of time that the sperm can be stored appears to differ depending on where it is being stored. If the sperm is stored in the cloaca, it lasts a relatively short time, whereas if it is stored in the upper end of the oviducts in vascular tissues specialized as seminal receptacles it seems to last much longer. Copperheads have a gestation period of three to nine months. They are a live-bearing snake, typically producing two to ten young; larger females produce larger broods. After birth, the female provides no direct care for the young.

Females are ovoviviparous (eggs develop in the body of the female and hatch within or immediately after being expelled). They produce large, yolk-filled eggs and store the eggs in the reproductive tract for development. The embryo, during this time, receives no nourishment from the female, only from the yolk. The young are expelled in a membranous sac and weigh less than an ounce (28 g) and measure seven to ten inches (17.8 to 25 .4 cm) in length

Life Span

The life span of the copperhead is up to 18 years.


No special status federally, however it is listed in the state of Massachusetts as endangered.

Fun Facts

The copperhead has solenoglyphous fangs that can be .3 inches (7.2 mm) in length. The length of the fangs is related to the length of the snake; the longer the snake, the longer the fangs. Even newborn copperheads have fully functional fangs that are capable of injecting venom that is just as toxic as adult venom. The fangs are replaced periodically, with each snake having a series of five to seven replacement fangs in the gums behind and above the current functional fang.

The copperhead is the cause of many snakebites yearly but they are rarely fatal. Bites occur when people accidentally step on or touch the snake, which tends to be well camouflaged in its surroundings. When touched, the copperhead quickly strikes or remains quiet and tries to crawl away. Sometimes when touched, they emit a musk that smells like cucumbers.

They are also known as the highland moccasin because of their highland habitat and the Native American word for these snakes is mokasen.

Source of Information

All or part of this information was provided by the Animal Diversity Web and Museum of Zoology of the University of Michigan.

It appears here with their permission. The original author of this information was John Saari.

For more information, including references, see the Animal Diversity Web account for this species, here:
http://animaldiversity.ummz.umich.edu/ site/ accounts/ information/ Agkistrodon_contortrix.html.