Venomous snakes in Iowa
Venomous snakes living in Iowa
4species
Prairie rattlesnake, Timber rattlesnake, Copperhead, Eastern massasauga. A bite from any of these is a medical emergency.
How to recognize them
Prairie rattlesnakeDangerous27 records, 2 counties
Timber rattlesnakeDangerous68 records, 6 counties
CopperheadMedically significant3 records, 2 counties
Eastern massasaugaMedically significant16 records, 8 counties
Prairie rattlesnake Crotalus viridis
- Greenish gray to brown with dark blotches down the back
- Blotches narrow into bands near the tail
- Two pale lines on the side of the face
Timber rattlesnake Crotalus horridus
- Dark V- or chevron-shaped bands across the back
- Black tail ending in a rattle
- Yellow, tan or dark phases; some are almost black
Copperhead Agkistrodon contortrix
- Copper to tan body with dark hourglass bands: wide on the sides, narrow on the spine
- Plain coppery head with no pattern
- Young snakes have a bright yellow-green tail tip
Eastern massasauga Sistrurus catenatus
- Gray or brown with large dark blotches down the back
- Small rattle
- Nine large plates on top of the head
Every venomous snake species known from the US is on this site.
Counties with records
- None recorded
- 1 species
- 2
- 3 to 4
- 5 or more
Active months
Harmless snakes people mistake for them
- Copperhead vs Northern Water Snake Northern water snake: harmless
- Copperhead vs Rat Snake Rat snake: harmless
- Copperhead vs Milk Snake Milk snake: harmless
- Copperhead vs Hognose Snake Eastern hognose snake: harmless
Water snakeHarmlessHarmless
Northern water snakeHarmlessHarmless
Eastern hognose snakeHarmlessHarmless
Rat snakeHarmlessHarmless
Milk snakeHarmlessHarmless
Gopher snakeHarmlessHarmless
Quick answers
- Lives here Are there rattlesnakes in Iowa?
- Lives here Are there copperheads in Iowa?
- Not here Are there cottonmouths in Iowa?
Questions
How many venomous snakes are in Iowa?
4 species live in the state: Prairie rattlesnake, Timber rattlesnake, Copperhead and Eastern massasauga.
Which venomous snakes in Iowa are dangerous?
Prairie rattlesnake, Timber rattlesnake, Copperhead and Eastern massasauga: a bite is a medical emergency.
When are venomous snakes most active in Iowa?
Most open records fall in May, August.
Which harmless snakes get mistaken for venomous ones in Iowa?
Northern water snake, Rat snake, Milk snake and Eastern hognose snake. See the side-by-side comparisons below.