Species guide
Cottonmouth
VenomousAgkistrodon piscivorus
What does Cottonmouth look like?
A thick-bodied dark snake of southeastern US wetlands. When threatened it gapes to show a startling white ('cotton') mouth lining, and it has a blocky head and vertical pupils. Often stands its ground.
Is Cottonmouth dangerous?
Venomous — a bite is serious and needs urgent medical care, though it would rather warn (gaping, musking) than strike. Harmless water snakes are often killed by mistake for it.
Commonly confused with
- Northern water snake — harmless, with round pupils, and it flees rather than gaping
What should I do about Cottonmouth?
Back away and give it room; never handle it or try to kill it. Seek emergency care if bitten.
Recorded 24,038 times in the wild worldwide.
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