Nerodia is a genus of non-venomous colubrid snakes commonly referred to as water snakes.
species vary greatly, but all are relatively heavy-bodied snakes, sometimes growing to 4 feet or larger. They have flattened heads, with small eyes that have round pupils
, and keeled scales. Species like N. fasciata
display distinct banding, where other species, like N. erythrogaster
have blotching, and N. rhombifer
have diamond-shaped patterning. Most species are brown or olive green, or some combination therein with markings being brown, or black. Yellow or cream-colored accenting is common.
Water snakes, as their name implies are largely aquatic. They spend the vast majority of their time in, or very near permanent sources of water. Often they can be found basking on tree branches which overhang slow moving streams or ponds. Their primary diet is fish and amphibians
, and they are quite adept at catching both in their aquatic environment. They will also consume rodents
While their initial instinct is to flee when disturbed, they do typically have a nasty disposition, and do not often hesitate to strike or bite if handled, and will often expel a foul-smelling musk from their cloaca.
Nerodia species are ovoviviparous, breeding in the spring and giving birth in the late summer or early fall. They are capable of having clutches with as many as 90 or more young, but generally they are much smaller. Neonates are around 8–10" in length.
Species & subspecies
- N. clarkii (Baird & Girard, 1853), Salt marsh snake
- Nerodia cyclopion (Duméril, Bibron & Duméril, 1854), Mississippi green water snake
- Nerodia erythrogaster (Forster, 1771), Plain-bellied water snake
- N. e. alta (Conant, 1963)
- N. e. bogerti (Conant, 1953)
- N. e. erythrogaster (Forster, 1771), Redbelly water snake
- N. e. flavigaster (Conant, 1949), Yellowbelly water snake
- N. e. neglecta (Conant, 1949), Copperbelly water snake
- N. e. transversa (Hallowell, 1852), Blotched water snake
- Nerodia fasciata (Linnaeus, 1766)
- Nerodia floridana (Goff, 1936), Florida green water snake
- Nerodia harteri (Trapido, 1941), Brazos River water snake
- Nerodia paucimaculata (Tinkle & Conant, 1961), Concho water snake
- Nerodia rhombifer (Hallowell, 1852), Diamondback water snake
- Nerodia sipedon (Linnaeus, 1758)
- Nerodia taxispilota (Holbrook, 1838), Brown water snake
species are widely spread around the southern and eastern half of the United States
, north into Canada
and south into Mexico
, as well as to the island of Cuba
. Many ranges overlap, and intergrading
of subspecies is not unknown, but is rare.
- N. clarkii - around the Gulf of Mexico (Florida, Louisiana, Mississippi, Texas) and Cuba.
- N. cyclopion - Texas, Louisiana, Arkansas, Missouri, Illinois, Mississippi, Alabama, Georgia, Florida, South Carolina, Tennessee, and Kentucky.
- N. erythrogaster - Texas, Oklahoma, Kansas, Louisiana, Arkansas, Missouri, Mississippi, Alabama, Georgia, Florida, South Carolina, North Carolina, Illinois, Indiana, Ohio, Michigan, Iowa, Delaware and into Mexico ((Durango, Zacatecas, Coahuila, Nuevo Leon).
- N. fasciata - Texas, Louisiana, Oklahoma, Arkansas, Mississippi, Alabama, Florida, Georgia, South Carolina, North Carolina, Missouri, and Illinois.
- N. floridana - South Carolina, Florida, and Georgia.
- N. harteri - Central Texas.
- N. paucimaculata - Central Texas.
- N. rhombifer - Texas, Oklahoma, Kansas, Louisiana, Arkansas, Missouri, Illinois, Indiana, Tennessee, Mississippi, and Alabama, as well as south into Mexico (Coahuila, Nuevo Leon, Tamaulipas, Veracruz)
- N. sipedon - Colorado, Nebraska, Kansas, Oklahoma, Iowa, Missouri, Arkansas, Minnesota, Wisconsin, Illinois, Tennessee, Louisiana, Mississippi, Alabama, Georgia, Florida, South Carolina, North Carolina, Kentucky, West Virginia, Virginia, Indiana, Ohio, Pennsylvania, New York, Vermont, New Hampshire, Maine, Massachusetts, Connecticut, New Jersey, Delaware, Maryland, Michigan, and north into Canada.
- N. taxispilota - Florida, Alabama, Georgia, South Carolina, North Carolina, and Virginia.
Due to how widespread and extremely common they are in the wild, water snakes are often found in the exotic pet trade, throughout the United States, though they are rarely captive bred. Their relative physical unattractiveness compared to other available pet snake species, and their poor disposition makes them less than attractive pets. They are easy to care for though, and do quite well in captivity.
Some species, such as N. harteri
and N. paucimaculata
are only found in very isolated localities and are protected by state laws, but the majority of Nerodia
species hold no specific conservation status. Due to their habitat choice, poor disposition, and vague similarity to the venomous cottonmouth (Agkistrodon piscivorus
), they are frequently mistaken for them. This results in many more water snakes being killed every year than cottonmouths. Often, water snakes found in areas where the cottonmouth does not range are still killed by humans out of ignorance and fear.