This article includes a list of general references, but it lacks sufficient corresponding inline citations .(April 2014) |
Nerodia | |
---|---|
Nerodia rhombifer , diamondback water snake | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Reptilia |
Order: | Squamata |
Suborder: | Serpentes |
Family: | Colubridae |
Subfamily: | Natricinae |
Genus: | Nerodia Baird & Girard, 1853 |
Synonyms [1] | |
Clonophis, Coluber, Ischnognathus, Natrix, Regina, Storeria, Tropidoclonion, Tropidonothus, Tropidonotus, Vipera Contents |
Nerodia is a genus of nonvenomous colubrid snakes commonly referred to as water snakes due to their aquatic behavior. The genus includes nine species, all native to North America. Five of the species have recognized subspecies.
Nerodia species vary greatly, but all are relatively heavy-bodied snakes, sometimes growing to 1.2 m (4 feet) or longer in total length (including tail). They have flattened heads, with small eyes that have round pupils, and keeled dorsal scales. Species like N. fasciata display distinct banding, whereas other species, like N. erythrogaster , have blotching, and those like N. rhombifer have diamond-shaped patterning. Most species are brown or olive green, or some combination thereof with markings being brown, or black. Yellow or cream-colored accenting is common.[ citation needed ]
As the common name water snakes implies, species in the genus Nerodia 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 that overhang slow-moving streams or ponds.[ citation needed ]
The primary diet of Nerodia species is fish and amphibians, and they are quite adept at catching both in their aquatic environment. They will also consume small reptiles and rodents that live near water.[ citation needed ]
While their initial instinct is to flee when disturbed, water snakes of the genus Nerodia readily defend themselves if they are unable to escape. They do not often hesitate to strike or bite if handled, and often expel a foul-smelling musk from their cloacae.[ citation needed ]
Nerodia species are viviparous, breeding in the spring and giving birth in the late summer or early fall. They are capable of having 90 or more young, but broods generally are much smaller. Neonates are around 20–26 centimetres (8–10 in) in length.[ citation needed ]
These species and subspecies are recognized as being valid: [2]
Nerodia species are widely spread throughout 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. Two species of Nerodia are invasive in the southwest US. [3]
Due to how widespread and extremely common they are in the wild, water snakes of the genus Nerodia are often found in the exotic pet trade, throughout the United States, though they are rarely captive bred. Their relative physical plainness, compared to other available pet snake species, and their propensity to bite make them less than attractive pets to most people. They are easy to care for, though, and do quite well in captivity.[ citation needed ]
Some Nerodia 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, defensive 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.[ citation needed ]
Agkistrodon piscivorus is a species of venomous snake, a pit viper in the subfamily Crotalinae of the family Viperidae. It is one of the world's few semiaquatic vipers, and is native to the Southeastern United States. As an adult, it is large and capable of delivering a painful and potentially fatal bite. When threatened, it may respond by coiling its body and displaying its fangs. Individuals may bite when feeling threatened or being handled in any way. It tends to be found in or near water, particularly in slow-moving and shallow lakes, streams, and marshes. It is a capable swimmer, and like several species of snakes, is known to occasionally enter bays and estuaries and swim between barrier islands and the mainland.
Nerodia rhombifer, commonly known as the diamondback water snake, is a species of nonvenomous natricine colubrid endemic to the central United States and northern Mexico. There are three recognized subspecies of N. rhombifer, including the nominotypical subspecies.
Nerodia erythrogaster, also known as the plain-bellied water snake or plainbelly water snake, is a common species of semi-aquatic, non-venomous colubrid snake endemic to the United States.
The Florida cottonmouth is a species of venomous snake, a pit viper in the subfamily Crotalinae of the family Viperidae. The species is endemic to the United States, where it occurs in southern Georgia and the Florida peninsula in nearly every type of wetlands in the region, including brackish water and offshore islands. However, it is not entirely dependent on water and is occasionally encountered as far as a mile from surface water. Agkistrodon conanti venom is very hemolytic and known to cause relatively extensive necrosis compared to many snake venoms, and can sometimes be lethal with a 17% mortality rate. It is often confused with harmless watersnakes (Nerodia) and other semi-aquatic species with which it shares its habitat.
Nerodia paucimaculata, commonly known as the Concho water snake, is a species of mostly aquatic, nonvenomous snake in the family Colubridae. The species is endemic to Texas in the United States.
The Brazos water snake, also called commonly Harter's water snake, is a species of mostly aquatic, nonvenomous snake in the family Colubridae. The species is endemic to Texas in the United States.
The banded water snake or southern water snake is a species of mostly aquatic, nonvenomous, colubrid snakes most commonly found in the Midwest, Southeastern United States.
Nerodia clarkii, commonly known as the salt marsh snake, is a species of semi-aquatic, nonvenomous, colubrid snake found in the southeastern United States. Their range extends along the brackish salt marshes of the Gulf of Mexico and the Atlantic Coast from Texas to Florida, with an additional population in northern Cuba. Different subspecies of this snake are primarily identified via color patterns on each snake's belly, or anterior.
The crayfish snake, also known commonly as the glossy crayfish snake, the glossy swampsnake, the glossy water snake, and the striped water snake, is a species of semiaquatic snake in the subfamily Natricinae of the family Colubridae. The species is endemic to the southeastern United States, and preys mainly on crayfish.
The Florida banded water snake, a subspecies of the banded water snake, is a nonvenomous natricine colubrid native to the southeastern United States.
The green water snake is a common species of nonvenomous natricine snake endemic to the southeastern United States.
The brown water snake is a large species of nonvenomous natricine snake endemic to the southeastern United States. This snake is often one of the most abundant species of snakes found in rivers and streams of the southeastern United States, yet many aspects of its natural history are poorly known. Due to abundance and distribution throughout its biological range, this species could be used to investigate anthropogenic impacts on aquatic ecosystems by studying their movements.
The midland water snake, a subspecies of the northern water snake, is a nonvenomous natricine snake, which is endemic to North America.
Nerodia floridana, commonly known as the Florida green watersnake, or eastern green watersnake, is a harmless species of snake in the subfamily Natricinae of the family Colubridae. The species is native to the southeastern United States.
The common watersnake is a species of large, nonvenomous, common snake in the family Colubridae. The species is native to North America. It is frequently mistaken for the venomous cottonmouth.
Nerodia clarkii clarkii, the Gulf salt marsh snake, is a subspecies of N. clarkii that is indigenous to the south-eastern United States. It is a nonvenomous, colubrid snake that inhabits coastal salt marshes and brackish estuaries along the coast of the Gulf of Mexico from Florida to Texas.