Agkistrodon Contortrix

Agkistrodon contortrix, also known as the eastern copperhead snake, is a venomous type of viper snake native to forests throughout the eastern North American continent. Easily distinguishable by its vibrant copperhead with hourglass shape markings, this snake differs from other vipers by “freezing” when they encounter humans. That said, they still bite more people than any other snake in America because their camouflage is so effective that people will accidentally step on them! 

Read on to learn more about this bronze-colored, beautiful snake. 

Agkistrodon Contortrix Amazing Facts

• Copperheads get their name from the bronze color of their heads and the copper-colored hues of their scales and markings.
• The Union called northern democrats who were against the Civil War “copperheads” — perhaps a bit unfairly!
• These snakes are native to the eastern forests of North America, preferring the shade of trees to more arid regions.
• Agkistrodon contortrix venom is not lethal to humans if one seeks immediate medical attention. Their toxin breaks down red blood cells and knocks their victims out of commission.
• The largest recorded length for the Agkistrodon contortrix is 53 inches long, from a specimen found in the 1930s.
• Copperheads have glands called “pits” located between the eyes and nostrils that are used to sense heat — hence the family name “pit viper” — and help them track the motion and presence of prey.

Where To Find Agkistrodon Contortrix 

The Agkistrodon contortrix is native to North America and found in the deciduous forest regions of the United States. The snake resides as far north as Massachusetts, south as Georgia, and west as northern Mexico and Texas. Due to its broad geographical range, the species has adapted to suit a variety of habitats, including mixed woodlands, river edges, rocky cliffsides, and even the edges of wetlands. Some have been found near human habitation in construction sites or rural, dirt-laden regions.

During hibernation, snakes curl up in logs, caves, and crevices to stay warm and safe from would-be predators. 

Agkistrodon Contortrix Scientific Name

This is the snake’s scientific name and Agkistrodon contortrix is loosely translated as “fishhook-toothed snake” with “twisted” designs. The word Agkistrodon comes from the Greek term ancistro, meaning “hooked,” and odon, translated to “tooth.” The second word Contortrix has a Latin origin in the phrase contortus, which means “twisted” or “intricate.” This refers to the twisting, hourglass-like patterns on the copperhead’s back that are an identifying characteristic.

The most common name people know for this snake is the copperhead. There are four subspecies of Agkistrodon contortrix, but the most common one is the Agkistrodon contortrix mokasen, found in the southern United States and as northward as Massachusetts’ forests.

Agkistrodon Contortrix Population & Conservation Status 

The eastern copperhead is a common snake in its territorial range with a conservation status of most minor concern. 

How To Identify Agkistrodon Contortrix: Appearance and Description 

The copper-colored head and lovely, dark-brown hourglass designs on its body are the Agkistrodon contortrix’s most defining characteristics. Other snakes sport similar colors, but the hourglass shape bands set the eastern copperhead apart from its fellow vipers. 

Agkistrodon contortrix are smaller in size, with slender necks and a length ranging from two to four feet on average. These snakes feature pale-colored bellies with black, gray, or brown mottled colors. Its scales lay upside down, and its eyes flash vertical slits for pupils, similar to a cat’s in appearance. The eyes can be orange, red, or tan.

Young snakes are usually grayer than their adult counterparts, sporting yellow or green tails that eventually darken into bronzer hues. Its lighter-colored tail serves as a lure for prey, helping the young snake attract animals who mistake its tail for a worm or insect food.

Agkistrodon Contortrix Venom: How Dangerous Are They?

These snakes aren’t as dangerous as others in the pit viper family for a variety of reasons. Agkistrodon contortrix aren’t nearly as aggressive as other snakes, and their venom isn’t as potent. Eastern copperhead venom is a hemotoxin, meaning it attacks red blood cells. Researchers estimate it would take approximately 100 milligrams of venom to kill a human; very few people have died from an eastern copperhead bite. That said, their venom still requires medical attention. 

Additionally, Agkistrodon contortrix will deliver dry bites to warn off would-be attackers. These bites contain little to no venom and often occur when a snake is stepped on or otherwise agitated. When venom is mixed into the bite, symptoms include severe pain, nausea, swelling of the bite site, and tingling sensations. Copperhead bites can injure muscles or bones, especially in a hand or foot if that’s where they occur.

Interestingly, researchers discovered that eastern copperhead venom contains a protein called “contortrostatin” with evidence indicating that it halts cancer cell growth in mice. The protein was also shown to inhibit the movement of cancerous cells in the body, keeping tumors in one spot instead of spreading. Despite this promising evidence, further clinical research is required to verify results and effectiveness.

Agkistrodon Contortrix Behavior and Humans

Eastern copperheads are described more often as shy than aggressive. They are diurnal in the spring and fall but become nocturnal during the hotter summer months. These snakes hibernate during the winter, but if the weather’s warm enough, they may choose to leave their den to sun themselves.

Agkistrodon contortrix are unique when they encounter danger in that they freeze in place rather than escape or attack the threat. Copperheads rely on the camouflage of fallen leaves or similar-colored dirt to hide them from predators and usually find success. When predators get too close, they’ll vibrate their tale and create a noise similar to that of rattlesnakes. 

When hunting, Agkistrodon contortrix will still and wait for prey to walk within biting distance. They use their venom to paralyze their prey or simply hold it in their mouths if the food is small enough. Copperheads will swallow their food whole, with a diet ranging from various insects like spiders and grasshoppers to frogs, lizards, small rodents, and rabbits. Occasionally, these pit vipers will feed on carrion. Pregnant females, conversely, fast or consume small amounts of food until they reproduce.

Breeding season occurs in late summer. Males seek a mate by flicking their tongs and sensing female pheromones, and they sometimes will fight over the attention of a female. Females can mate with many males and produce a litter with several different fathers. Interestingly, females may not become gravid immediately, storing sperm until after hibernation to begin the gestation period, usually 80 to 150 days. Females can breed between every one to three years.

Agkistrodon contortrix do not nest; instead, they give birth in crevices in rocky cliffsides or rock formations called a rookery. Copperheads give birth to live young in a litter that averages four to seven new snakes, though litters of up to 21 young snakes have occurred. Following delivery, the mother will stay with the babies for a few days before they venture out into the world. Young snakes are ready for mating at about 3.5 years of age and can live as long as 29 years.

Up Next

• Viper
• Pit Viper
• Snake

1. Virginia Herpetological Society, Available here: https://www.virginiaherpetologicalsociety.com/reptiles/snakes/copperhead/copperhead.php
2. Florida Museum, Available here: https://www.floridamuseum.ufl.edu/florida-snake-id/snake/eastern-copperhead/
3. Missouri Department of Conservation, Available here: https://mdc.mo.gov/discover-nature/field-guide/eastern-copperhead
4. iNaturalist, Available here: https://www.inaturalist.org/taxa/912622-Agkistrodon-contortrix