Eastern Diamondback Rattlesnake
Crotalus adamanteus
Also called: diamondback, eastern diamondback
The largest rattlesnake and the heaviest venomous snake in the United States, found in the sandy pine and palmetto country of the Southeast.
- Kind
- Venomous
- Typical length
- 3 to 6 feet (the thickest rattlers reach more)
- Range
- The southeastern coastal plain, from North Carolina through Florida and west to Louisiana
- Regions
- Southeast
- Habitat
- Woods & forest, Grass & prairie
- When active
- Warm months, and on mild winter days
Note: Eastern diamondbacks are shy, declining in many places, and legally protected in some states. A bite is a medical emergency.
How to identify it
- Large dark diamonds with cream or yellowish borders run down a brown, olive, or gray body.
- Two pale diagonal lines cross each side of the face, one running through the eye.
- The body is very thick and heavy, and the tail ends in a rattle.
- The head is wide and triangular, clearly broader than the neck.
Often confused with
- Western Diamondback Rattlesnake: a similar pattern, but it lives in the dry Southwest, and its tail has bold black and white bands.
- Eastern Hognose Snake: blotched like a rattler and happy to bluff, but it has a pointed, upturned nose and no rattle.
If you meet one
- Stop and look before you step. Check where your feet and hands will land, especially near logs, rocks, and brush.
- Back away slowly and give the snake plenty of room, at least several body lengths. It wants to leave, not fight.
- Do not try to kill, catch, move, or photograph it up close. Most bites happen to people doing exactly that, and a dead snake can still bite by reflex.
If someone is bitten
- Move away from the snake and call 911 right away.
- Keep the person calm and as still as possible. Take off rings, watches, and tight clothing near the bite before swelling starts.
- Keep the bitten area still and about level with the heart, and get the person to a hospital. Antivenom is the treatment.
- Do not cut the bite, suck out venom, use a tourniquet, apply ice, or give alcohol. These make things worse.
- In the U.S., Poison Help (1-800-222-1222) can advise while you wait for help. Do not wait to see whether symptoms develop.
Field notes
The eastern diamondback lives in longleaf pine flatwoods, palmetto scrub, and coastal dunes. It often shelters in gopher tortoise burrows or under stumps and palmetto thickets. It rattles to warn, but not every snake does, so stay alert in its range.
Related guides
This page is a general reference, not medical advice and not a substitute for identifying a real snake with an expert. Many snakes are protected by state law, and rules about killing or handling them vary, so check your state wildlife agency; our state resources directory links to each one. For any bite, get emergency care.