Eastern Diamondback Rattlesnake
VenomousCrotalus adamanteus · also called diamondback
The eastern diamondback is the largest venomous snake in North America and among the most dangerous, combining considerable size with long fangs and a high venom yield. It is a species of southeastern pine flatwoods and coastal scrub, and it has declined sharply through habitat loss. Encounters are far less common than they once were.
Before anything else
- Back away and leave it alone. A snake that can see you leaving has no reason to bite. Most bites in the United States happen to people who picked up, cornered, or tried to kill a snake.
- Never handle a snake to identify it. Every identification on this site can be made from a photo or from several feet away.
- If someone is bitten, call emergency services now. Keep the limb still and below the heart, remove rings and watches, and go to hospital. Do not cut, suck, apply ice, or use a tourniquet — all of these make outcomes worse.
- Do not try to catch the snake for identification. A photo from a distance is enough, and hospitals treat symptoms rather than species.
In the US, the Poison Help line is 1-800-222-1222. This site is a reference, not medical advice.
Quick facts
- Venom
- One of the most medically serious snakebites in North America. Bites are emergencies requiring antivenom. Keep well clear, keep dogs leashed, and do not attempt to move one.
- Adult length
- 33–72 inches (84–183 cm)
- Markings
- Large dark diamonds down the back, each crisply outlined in cream or yellow. Two pale diagonal lines cross the side of the face. The pattern is the sharpest and most clearly defined of any North American rattlesnake.
- Habitat
- woods, grassland, suburban
- Family
- pit viper
- Range
- 7 US states
How to identify a eastern diamondback rattlesnake
- Sharply outlined dark diamonds bordered in cream — the crispest pattern of any US rattlesnake.
- Two pale diagonal stripes on the side of the face, one through the eye.
- Rattle at the tail tip, though a rattle can be broken off and missing.
- Very heavy-bodied. A large adult is unmistakably thick, not a slender snake.
What it does when it sees you
Usually holds its ground when disturbed, coiling and rattling loudly. Like all rattlesnakes it would far rather be left alone than bite, and rattling is a request for exactly that.
What the eastern diamondback rattlesnake is confused with
One test settles each of these.
Hognose snakes have an upturned pig-like snout, no rattle, and flatten their necks into a cobra-like hood before playing dead.
Timber rattlesnakes have dark V-shaped or chevron crossbands rather than diamonds, and a solid black tail.