Introduction: Copperhead (Agkistrodon contortrix) and cottonmouth or water moccasin (Agkistrodon piscivorus) snakes account for the majority of venomous snakebites in the southern United States. Cottonmouth snakes are generally considered to have more potent venom. Copperheads are considered less venomous and there is some controversy as to whether or not bites from copperhead snakes need to be treated with antivenom. Copperhead and juvenile cottonmouth snakes are both brown in color. The purpose of this study was to evaluate the accuracy of identification by the public and healthcare providers between these two species.
Methods: Snakebite victims sometimes bring dead snakes to the hospital or have taken pictures of the snake. When this occurred, ED personnel were asked to take a picture of the snake, and forward the picture to the state poison control center. The identification of the snake by witnesses and/or hospital personnel was compared to the identification by the state herpetologist.
Results: During the study period, there were 286 cases of snakebites reported to the state poison control center. Pictures were obtained on 49 of the responsible snakes. All copperhead snakes were identified correctly by callers. However, only 21% of cottonmouth snakes were identified correctly, with 74% of cottonmouth snakes being identified as copperheads. Both public and medical personnel performed poorly on identification of cottonmouth snakes.
Conclusions: Forty percent of the snakes identified as copperheads were actually cottonmouth snakes. Juvenile cottonmouth snakes were often identified as copperhead snakes.
Copperheads and cottonmouths are two of the most commonly encountered venomous snakes in the southeastern United States. They also happen to look very similar which can make differentiating between them difficult. However, being able to properly identify these snakes is extremely important as the venom toxicity and recommended treatment differs between the two species.
In this article, we’ll go over the key differences between copperheads and cottonmouths to help you confidently identify them We’ll cover similarities in appearance, habitat, behavior, diet, reproduction, venom toxicity, and more.
Appearance and Size
Copperheads and cottonmouths have stocky, thick bodies that become more slender towards the tail. They both reach similar maximum lengths of around 4 feet, though copperheads are more commonly in the 2-3 foot range while cottonmouths are more commonly 3-4 feet.
Copperheads have tan, pinkish, or gray bodies with distinct hourglass-shaped brown crossbands down the length of their bodies. Their namesake copper-colored head is usually a solid, coppery-orange-red color that contrasts with the body.
Cottonmouths have very variable coloration but most are some shade of brown, tan, olive, or black. Many have vague banding patterns that fade with age, and old cottonmouths can appear solid black. Juveniles have bright yellow or greenish tails.
Habitat and Range
Copperheads prefer dry, rocky upland areas and hillsides but also thrive in mixed forests and wooded suburban areas. Their range extends over much of the eastern and central United States from Texas to Massachusetts.
Cottonmouths are strongly associated with water and wetlands like swamps, marshes, and streams. They occur primarily in the southeastern states from East Texas to South Virginia.
Behavior
Copperheads are generally shy, calm snakes that prefer to freeze or flee from threats. They are not known for aggression and only bite defensively as a last resort.
Cottonmouths have a reputation for being ill-tempered and quick to defend themselves. They may gape their mouth open as a threat display. However, cottonmouths still typically avoid confrontation if possible.
Diet and Hunting
Copperheads mostly eat small mammals like mice, voles, and shrews. They also eat amphibians, lizards, smaller snakes, and some insects. They ambush prey by striking and then releasing to let the venom take effect.
As semi-aquatic snakes, cottonmouths prey heavily upon fish, frogs, smaller reptiles, and small mammals near the water’s edge. They may also scavenge dead animals opportunistically.
Reproduction
Copperheads and cottonmouths both mate in the spring. Females give birth to live young in late summer or fall. Average litter sizes are 4-10 for copperheads and 6-12 for cottonmouths. The neonates are about 6-10 inches long at birth.
Venom Toxicity
Cottonmouth venom is far more toxic and fast-acting than copperhead venom. Cottonmouth bites can be rapidly fatal if left untreated and require immediate medical attention.
Copperhead bites rarely kill healthy adult humans as the venom is somewhat milder. Still, their bites can cause severe localized tissue damage and pain if not treated promptly.
Geographic Overlap
There is significant overlap between copperhead and cottonmouth range in the southeastern states. If you can’t positively identify a suspected cottonmouth or copperhead, exercise extreme caution and leave it alone. Seek medical attention for any snakebite to be safe.
Your saved search Name of saved search: Search terms:
- Yes
- No
Email:
Save citation to file Format:
- Create a new collection
- Add to an existing collection
Name your collection: Name must be less than 100 characters Choose a collection: Unable to load your collection due to an error
Cottonmouth VS Copperhead!
FAQ
Are Cottonmouths or copperheads more aggressive?
Their study found that Cottonmouths were non-aggressive and were unlikely to bite in an encounter with a human. The Eastern Copperhead (Agkistrodon contortrix) is one of the most common and widespread venomous species in the US, and many people live in fear of them and kill individuals on sight.
Can you survive a copperhead bite without antivenom?
You can probably survive a bite from a copperhead without treatment; over 5000 people get bitten per year and about 5 of those are fatal(1 die per every 1000 bites on a rough estimate).
Is a water moccasin a copperhead?
-
Cottonmouth (Water Moccasin):
- Also known as the cottonmouth, they are a semi-aquatic species, meaning they spend a lot of time near water, like swamps, wetlands, and slow-moving streams.
- They are part of the pit viper family (Viperidae) and the genus Agkistrodon.
- They are found in the southeastern United States, including Florida.
- They are known for their white mouth lining, which they reveal when threatened.
- They have a reputation for being aggressive, but are actually more likely to flee than to attack.
- Also known as the cottonmouth, they are a semi-aquatic species, meaning they spend a lot of time near water, like swamps, wetlands, and slow-moving streams.
-
- They are also a venomous pit viper, but they are not as closely associated with water as cottonmouths.
- They are found in a wider range of habitats, including woodlands, rocky areas, and brushy areas.
- They are also in the genus Agkistrodon.
- They are found in the eastern United States.
- They are known for their copper-colored head and reddish-brown bands.
- They are also a venomous pit viper, but they are not as closely associated with water as cottonmouths.
-
Key Differences:
- Habitat: Cottonmouths are primarily found near water, while copperheads are more terrestrial and found in a variety of habitats.
- Appearance: Cottonmouths have a rougher, more jagged pattern on their bodies compared to the more smooth pattern of copperheads.
- Venom: While both are venomous, cottonmouth venom is considered more potent than copperhead venom.
- Habitat: Cottonmouths are primarily found near water, while copperheads are more terrestrial and found in a variety of habitats.