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Venomous look-alikes

Cottonmouths vs. watersnakes

Venomous snakes can hurt you badly. Don't handle any snake you can't identify for certain. The Common Watersnake, Banded Watersnake, and Plain-bellied Watersnake are harmless but often mistaken for the venomous Northern Cottonmouth and Florida Cottonmouth.

How to tell them apart

  • Many scientists dislike the use of the term water moccasin since it can lead to confusion between the venomous cottonmouth and nonvenomous water snakes. Wikipedia ↗
  • Nerodia fasciata is often mistaken for venomous cottonmouths (Agkistrodon piscivorous) despite the differences in their physical appearance. Animal Diversity Web ↗
  • The diamondback water snake is often mistaken for the cottonmouth or rattlesnakes and is killed out of fear. Wikipedia ↗
  • Nerodia taxispilota is found in swamps and streams and is often mistaken for a moccasin. Wikipedia ↗

Venomous

⚠ venomous
Northern Cottonmouth

Northern Cottonmouth

Agkistrodon piscivorus

kirk gardner · CC BY 4.0

⚠ venomous
Florida Cottonmouth

Florida Cottonmouth

Agkistrodon conanti

William J. Deml · CC BY 4.0

Harmless look-alikes

These get killed all the time because people mistake them for the snakes above. They're harmless to people.

Common Watersnake
Common WatersnakeNerodia sipedon
Banded Watersnake
Banded WatersnakeNerodia fasciata
Plain-bellied Watersnake
Plain-bellied WatersnakeNerodia erythrogaster
Diamondback Watersnake
Diamondback WatersnakeNerodia rhombifer
Brown Watersnake
Brown WatersnakeNerodia taxispilota
Florida Green Watersnake
Florida Green WatersnakeNerodia floridana
Mississippi Green Watersnake
Mississippi Green WatersnakeNerodia cyclopion

Quotes are word for word from the linked sources. Photo credits and licenses are on each species page. If you're not certain what a snake is, leave it alone.

Questions

How do you tell the Northern Cottonmouth from harmless snakes?

Many scientists dislike the use of the term water moccasin since it can lead to confusion between the venomous cottonmouth and nonvenomous water snakes.