Mangrove Salt Marsh Snake
Scientific name: Nerodia clarkii compressicauda KENNICOTT 1860
* Currently accepted name
* scientific names used through time
- Regina clarkii – BAIRD & GIRARD 1853
- Nerodia compressicauda – KENNICOTT 1860
- Tropidonotus compsolaemus – COPE 1860
- Tropidonotus ustus – COPE 1860
- Tropidonotus compressicaudus – COPE 1861
- Tropidonotus compressicaudus walkeri – COPE 1888
- Natrix compressicauda compressicauda – COPE 1888
- Natrix compressicauda compsolaemus – COPE 1888
- Natrix compressicauda walkeri – COPE 1888
- Natrix usta – COPE 1888
- Natrix compressicauda walkerii – COPE 1892
- Tropidonotus walkerii – COPE 1892
- Natrix compressicauda – COPE 1892
- Tropidonotus compressicauda – BOULENGER 1893
- Natrix sipedon compressicauda – CONANT 1958
- Natrix fasciata compressicauda – CONANT 1975
- Nerodia clarkii compressicauda – CONANT & COLLINS 1991
Average adult size is 14-28 inches (35.5-71.1 cm), record is 36.75 inches (93.3 cm). Adults are variable in color. They may be grayish-olive, brown, or rusty orange with faint darker bands. Some individuals may be almost entirely black. There may be dark stripes on the neck. The belly is reddish-brown on rusty orange individuals, clouded gray on olive-gray individuals, clouded tan on brownish individuals, or mostly black with a central row of light spots on black-colored individuals. The scales are keeled, and there are 21-23 dorsal scale rows at midbody. The pupil is round. Juvenile coloration is similar to adults.
A. Top of the head
B. Underside of the head (chin and throat)
C. Elongated scales below the tail (subcaudal scales) are typically divided
D. Front (face view) of the head
E. Side of the head
F. Keeled scales
Range: In Florida, it is found along the Gulf coast from central Florida south into the Florida Keys, and north to around Brevard Co. on the Altlantic coast. It is not found outside of Florida.
Habitat: Commonly found along the coast in brackish and saltwater estuaries, salt marshes, and tidal mud flats.
Comments: HARMLESS (Non-Venomous). The Mangrove Salt Marsh Snake is frequently seen basking above the water on the limbs of mangrove trees. It is active primarily at night, depending on tidal patterns and seasons. It inevitably ingests salt from its estuarine habitats. Since it does not have salt glands to help it get rid of excess salt, it must occasionally obtain freshwater, such as from rain, coastal streams, or body fluids of their prey.
It feeds on small fishes, crabs, shrimp, and other invertebrates trapped in isolated pools of water by the falling tide.
It is live-bearing. Young are 7 to 9.5 inches (17.7-24.1 cm) at birth. Up to 22 young have been recorded.
Comparison with other species: The Striped Crayfish Snake (Regina alleni) has a uniform light colored belly. The Queen Snake (Regina septemvittata) is much thinner and has only 2 light-colored stripes on its body.
It should not happen often, but some people might confuse a Salt Marsh Snake with a venomous Cottonmouth. However, it is easy to distinguish between Cottonmouths and Salt Marsh Snakes and other Water Snakes.