Copperhead Snake Facts

Scientific Name: Agkistrodon contortrix

Copperhead snake
Copperhead snake.

GlobalP, Getty Images

The copperhead snake (Agkistrodon contortrix) gets its common name from its coppery reddish-brown head. Copperheads are pit vipers, related to rattlesnakes and moccasins. Snakes in this group are venomous and have a deep pit on either side of the head that detects infrared radiation or heat.

Fast Facts: Copperhead

  • Scientific Name: Agkistrodon contortrix
  • Common Names: Copperhead, highland moccasin, pilot snake, white oak snake, chunk head
  • Basic Animal Group: Reptile
  • Size: 20-37 inches
  • Weight: 4-12 ounces
  • Lifespan: 18 years
  • Diet: Carnivore
  • Habitat: Eastern North America
  • Population: Over 100,000
  • Conservation Status: Least Concern

Description

Copperheads may be distinguished from other pit vipers by their color, pattern, and body shape. A copperhead is tan to pink with 10 to 18 darker hourglass- or dumbbell-shaped crossbands on its back. Its head is solid copper-brown. The snake has a broad head, distinct neck, stout body, and thinner tail. A copperhead has tan to reddish brown eyes and vertical pupils. The average adult snake is between 2 and 3 feet in length and weighs from 4 to 12 ounces. Females have longer bodies than males, but males have longer tails.

Habitat and Distribution

Copperheads live in the United States, from southern New England to northern Florida and across to western Texas. They extend into Chihuahua and Coahuila in Mexico. The snake occupies a variety of habitats, including forests, swamps, rocky woodlands, and along rivers and streams.

Copperhead snake range
Copperhead snake range. Craig Pemberton

Diet and Behavior

Copperheads are ambush predators that camouflage themselves against the leaves and soil and wait for prey. They find their targets by heat and scent. About 90% of their diet consists of small rodents. They also eat frogs, birds, smaller snakes, and large insects. Copperheads climb trees to forage on caterpillars and emerging cicadas, but are otherwise terrestrial. Except for mating and hibernating, the snakes are solitary.

The snakes hibernate in the winter, often sharing a den with other copperheads, rat snakes, and rattlesnakes. They feed during the day in spring and autumn, but are nocturnal during hot summer months.

Reproduction and Offspring

Copperheads breed anywhere from spring to late summer (February to October). However, neither males nor females necessarily breed every year. Males wrestle in ritual combat for breeding rights. The winner may then have to battle the female. The female stores sperm and may defer fertilization for several months, usually until after hibernating. She gives birth to 1 to 20 live young, each measuring about 8 inches in length. The young resemble their parents, but they are lighter colored and have yellowish-green tipped tails, which they use to lure lizards and frogs for their first meals. Baby copperheads are born with fangs and venom that is as potent as that of adults.

Females sometimes reproduce via parthenogenesis, an asexual mode of reproduction that does not require fertilization.

Copperheads reach sexual maturity when they are about 2 feet long, which is around 4 years of age. They live 18 years in the wild, but they may live 25 years in captivity.

Juvenile copperhead snake
Juvenile copperhead snakes have yellowish green tail tips. JWJarrett, Getty Images

Conservation Status

The IUCN classifies the copperhead conservation status as "least concern." Over 100,000 adult snakes live in North America, with a stable, slowly declining population size. For the most part, copperheads are not subject to significant threats. Habitat loss, fragmentation, and degradation diminish snake numbers about 10% every ten years. In particular, populations are geographically separated in Mexico.

Copperheads and Humans

Copperheads are responsible for biting more people than any other snake species. While the copperhead prefers to avoid humans, it freezes instead of slithering away. The snake is difficult to spot, so people unknowingly step too close or onto the animal. Like other New World vipers, copperheads vibrate their tail when approached. They also release a cucumber-smelling musk when touched.

When threatened, the snake usually delivers a dry (nonvenomous) bite or low-dose warning bite. The snake uses its venom to incapacitate prey prior to ingestion. Since people are not prey, copperheads tend to conserve their venom. However, even the full amount of venom is rarely fatal. Small children, pets, and persons allergic to snake venom are most at risk. Copperhead venom is hemolytic, which means it breaks red blood cells.

Bite symptoms include extreme pain, nausea, throbbing, and tingling. While it's important to seek immediate medical attention if bitten, usually antivenin is not administered because it poses a greater risk than the copperhead bite. Copperhead venom contains a protein called contortrostatin that may help slow tumor growth and cancer cell migration.

Sources

  • Ernst, Carl H.; Barbour, Roger W. Snakes of Eastern North America. Fairfax, Virginia: George Mason University Press, 1989. ISBN 978-0913969243.
  • Finn, Robert. "Snake Venom Protein Paralyzes Cancer Cells". Journal of the National Cancer Institute. 93 (4): 261–262, 2001. doi:10.1093/jnci/93.4.261
  • Frost, D.R., Hammerson, G.A., Santos-Barrera, G. Agkistrodon contortrix. The IUCN Red List of Threatened Species 2007: e.T64297A12756101. doi:10.2305/IUCN.UK.2007.RLTS.T64297A12756101.en
  • Gloyd, H.K., Conant, R. Snakes of the Agkistrodon Complex: A Monographic Review. Society for the Study of Amphibians and Reptiles, 1990. ISBN 0-916984-20-6.
  • McDiarmid, R.W., Campbell, J.A., Touré, T. Snake Species of the World: A Taxonomic and Geographic Reference, Volume 1. Washington, District of Columbia: Herpetologists' League, 1999. ISBN 1-893777-01-4.