Eastern copperhead

The eastern copperhead, known scientifically as Agkistrodon contortrix, is a widespread venomous snake. It is a member of the pit viper subfamily, Crotalinae, within the larger Viperidae family. These snakes are endemic to the eastern United States and parts of Mexico. They are significant to science because their venom may have medicinal value for humans. While they are common, they are also known for causing many snake bites in the United States. In fact, copperhead bites account for half of all treated snake bites in the country.

Physically, the eastern copperhead is characterized by a heavy, stout body type. Its most striking feature is a pattern of dark brown, hourglass-shaped markings. These markings are overlaid on a light reddish-brown or gray background. The name "contortrix" comes from the Latin word contortus, which means twisted or complex. This refers to how the bands are wide on the sides but pinched at the spine. The head is broad and distinct from the neck. Because the snout slopes backward, the top of the head extends further forward than the mouth.

Growth and development follow specific patterns for this species. Adult lengths typically reach about two feet, though some exceptional individuals may exceed four feet. There is often a difference in size between the sexes. Males generally do not exceed 28 inches and weigh between 10 and 15 ounces. Females are typically larger, often reaching 30 inches and weighing around 20 ounces. Young snakes, or neonates, are born with distinct green or yellow tail tips. These colorful tips transition to a darker brown or black within their first year of life.

Copperheads are habitat generalists, meaning they can survive in many different environments. In most of North America, they prefer deciduous forests and mixed woodlands. They are often found near rock outcroppings, ledges, or low-lying, swampy regions. In the southern United States near the Gulf of Mexico, they may inhabit coniferous forests. In the Chihuahuan Desert of Texas and Mexico, they live in riparian habitats near water. During the winter, they undergo hibernation in dens or limestone crevices. They often share these winter dens with timber rattlesnakes and black rat snakes.

As ambush predators, copperheads use a specific hunting strategy. They find a promising position and wait quietly for prey to arrive. Their diet is also quite varied, making them diet generalists. Juveniles tend to eat more invertebrates, such as arthropods, and ectotherms. As they grow into adults, they shift toward eating more vertebrate endotherms. Common prey items include cicadas, caterpillars, lizards, voles, and mice. Some copperheads have even been found in trees as high as 40 feet to hunt cicadas.

Behavioral traits help the copperhead survive in the wild. Unlike many other vipers, they often choose to "freeze" rather than slither away when approached. This behavior relies on their excellent camouflage, which helps them blend into dead leaves or red clay. They are generally nonaggressive and usually only strike as a last resort if touched. When they do feel threatened, they exhibit defensive tail vibration. This vibration can exceed 40 times per second, which is faster than most non-rattlesnake species.

Understanding the history and classification of the copperhead is an ongoing process. The genus name Agkistrodon comes from Greek words meaning "hook" and "tooth." Historically, scientists recognized five different subspecies. However, recent genetic analysis has provided new information about these species. While they are widespread, they are currently classified as "least concern" on the IUCN Red List. This means their population is considered stable and they are not at immediate risk of extinction.