Copperhead vs Northern Water Snake

The quick tellOn a copperhead the bands are wide on the sides and narrow on the back, like an hourglass. On a northern water snake they are wide on the back and narrow on the sides.

Photo: Peter Paplanus, CC BY 2.0, via Wikimedia Commons

Copperhead

Medically significant · 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
Cat-like vertical pupils and a pit between eye and nostril

Size: 24–36 in. Habitat: Wooded hillsides, rocky ridges, wood piles and suburban yards in the East and South.

The venomous snake behind most bites in the eastern US. Bites are painful and need medical care, but deaths are extremely rare.

Photo: Patrick Coin, CC BY-SA 2.5, via Wikimedia Commons

Northern water snake

Harmless · Nerodia sipedon

Dark crossbands near the head that break into blotches toward the tail
Bands are widest on the back, narrow on the sides (the opposite of a copperhead)
Round pupils, no heat pit
Belly with reddish half-moons

Size: 24–42 in. Habitat: Lakes, rivers, ponds and marshes from the Great Lakes to the Gulf states.

Not venomous. It bites if grabbed and musk smells bad, but it is harmless.

Where each one lives

Copperhead only
Northern water snake only
Both
Neither

Copperhead: 28 states. Northern water snake: 36 states. Both live in 28 states.

Side by side

	Copperhead	Northern water snake
Danger	Medically significant	Harmless
Size	24–36 in	24–42 in
States	28	36
Habitat	Wooded hillsides, rocky ridges, wood piles and suburban yards in the East and South	Lakes, rivers, ponds and marshes from the Great Lakes to the Gulf states

Questions

How can you tell a copperhead from a northern water snake?

On a copperhead the bands are wide on the sides and narrow on the back, like an hourglass. On a northern water snake they are wide on the back and narrow on the sides.

Which one is dangerous?

The copperhead: medically significant. The northern water snake: harmless. If you are not sure, keep your distance and do not handle it.

Where do both live?

Both live in 28 states: Alabama, Arkansas, Connecticut, Delaware, Florida, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maryland, Massachusetts, Mississippi, Missouri, Nebraska, New Jersey, New York, North Carolina, Ohio, Oklahoma, Pennsylvania, South Carolina, Tennessee, Texas, Virginia and West Virginia.