Florida Cottonmouth

Agkistrodon piscivorus conanti


The Florida cottonmouth, also called the cottonmouth moccasin and water moccasin, is one of three subspecies of the only venomous water snake in North America.


It ranges through the wetlands of Florida, southeastern Alabama and southern Georgia.




Any wetlands or waterway in the state




Adults average 20-48 inches in length, with a record length of 74 1/2 inches.


Heads are spade shaped; noticeably larger and thicker than their necks. 

When viewed from directly above, the eyes cannot be seen – unlike other water snakes. The pupil is vertical (catlike). There is a deep facial pit between the nostril and the eye.

Identification of this animal can be tricky as their color is variable and also changes as they get older. The eye is camouflaged by a broad, dark, facial stripe.  Dark brown cheek stripes are edged with light lines. The dark stripes running from the eyes backwards along the head are bordered top and bottom by a cream color. This is probably the best way to identify this subspecies since it holds true for all color variations, including those of the juveniles.  Faint brown stripes encircle the body. The chin is a light cream color. 

Juvenile cottonmouths have a bright, yellow tail (caudal lure) which they hold erect and wiggle like a caterpillar to attract prey within striking range. Their tail serves as a lure for frogs, a staple of their juvenile diets. Adults lose their juvenile coloration and become brownish black in color.

The cottonmouth is rather sluggish and is slow to move away if disturbed. Instead, when threatened, the cottonmouth may respond by vibrating its tail (like a rattlesnake), coiling its body and opening its mouth as though ready to bite. The exposed white interior of the mouth is what gave rise to the common name,”cottonmouth.” This open mouth threat display has led to the widespread belief that cottonmouths are aggressive snakes. In fact, they are one of the more sedate and if not hard pressed, the cottonmouth usually will retreat.  Note:  the snake does not  always display prior to striking. 

The bite of the moccasin can be lethal and they are able to bite underwater! Few fatalities have been recorded although their hemotoxic venom causes extensive local tissue damage.



Females are viviparous (retain egg sacs internally), the young hatch and give the appearance of live birth. The young have no parental care. This snake bears one to 15 babies, averaging seven inches in length.  The young are born alive and are venomous at birth.




Small mammals and birds as well as cold-blooded prey of various types. 



Status in the Wild:





Though the cottonmouth occurs throughout Florida, it is not as abundant as the many species of harmless water snakes that occur in much the same habitats. Many Florida residents do not even realize that other water snakes exist. As a consequence,  many large dark-colored snakes found near water are often killed, as a “cottonmouth.”




Web page, “List of Florida Snakes”, Copyright © 1999, 2000 Florida Museum of Natural History.