‹ Compare two snakes
Florida Cottonmouth vs Northern Cottonmouth
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(c) Jolieokefenokee, some rights reserved (CC BY)
Florida Cottonmouth
Agkistrodon conanti
VenomousMelanie Gaddy, no rights reserved
Northern Cottonmouth
Agkistrodon piscivorus
VenomousThe quick way to tell
Look at where you are first, then at the snout. In peninsular Florida it is the Florida Cottonmouth, which often has two dark vertical lines on the tip of the snout and a bold, pale-edged cheek stripe. Where the two ranges meet — southern Georgia, southern Alabama and the Florida Panhandle — they mix and can't be told apart by looks.
Head ★ This settles it
Broad, blocky triangular head, much wider than the neck, with a heavy brow. Bold dark cheek stripe with pale edges, and often two dark vertical lines on the tip of the snout.
Blocky, heavy brow, dark mask through each eye, pale snout.
Pattern
Dark, jagged crossbands on olive, brown or black; young snakes are reddish-brown and brightly banded.
Dark olive to nearly black, with faint wide bands clearest on young snakes.
Eyes
Vertical slit pupil, hidden by a dark stripe; the overhanging brow means you can't see the eyes from directly above.
Vertical slit pupil; heat-sensing pit between eye and nostril.
Pits
A deep heat-sensing pit on each side of the face, between the eye and the nostril.
A deep heat-sensing pit on each side of the face, between the eye and the nostril.
Tail
Dark in adults; babies have a bright sulfur-yellow tail tip.
Thick-based; young have a yellow tail tip.
What it does
Not aggressive, but often stands its ground, gaping its white mouth, vibrating its tail and releasing a strong musk.
Coils, vibrates its tail and gapes to show a white mouth lining.
Where it lives
All of Florida including the upper Keys, north into southern Georgia and west into southeastern Alabama.
Southeast from southeastern Virginia through the Carolinas, northern Georgia and Alabama, west to central Texas and Oklahoma, and up the Mississippi valley to southern Illinois, Missouri and southeastern Kansas.