The 7 True Water Snakes in Alabama

Snakes live throughout the state of Alabama in just about every kind of environment, but there’s a Genus of snake species that prefer to live in or near the water. It’s these snakes that we’re focusing on for this article, the water snakes in Alabama. Having said that, all species on this list of Alabama snakes (aside from the bonus snake at the end) will fall under the Genus Nerodia, true water snakes. There are around 9 species in this category with even more subspecies, and 8 of them can be found in Alabama.

All snakes are capable of swimming in water. While some rarely visit water, others are considered semi-aquatic. All true water snakes are in the Family Colubridae and are non-venomous. Water snakes often have large, heavy bodies and are commonly mistaken for venomous snakes. While they can bite if threatened and are even regarded as aggressive in some cases, they are quite harmless if left alone.

With that being said, let’s have a look at Alabama’s 7 types of water snakes.

7 Types of water snakes in Alabama

The 7 species of true water snakes found in Alabama are the midland water snake, diamond-backed water snake, plain-bellied water snake, brown water snake, banded water snake, salt marsh water snake, and the green water snake.

1. Midland Water Snake

midland water snake | image by Peter Paplanus via Flickr | CC BY 2.0

Scientific Name: Nerodia sipedon pleuralis
Length: 22-40 inches
Venomous: No

The midland water snake is a subspecies of the common water snake that’s found throughout Alabama. Their main prey items are frogs, fish, and even other snakes. Kingsnakes also are known to feed on other snakes. Their coloration is very similar to the copperhead and the cottonmouth, so they’re often mistaken for these two species.

Midland water snakes are non-venomous and kill their prey with constriction. They often mimic the behaviors of venomous cottonmouths, though, because their similar color patterns can fool potential predators into thinking they’re more dangerous than they really are.


2. Banded Water Snake

banded water snake | image by Dan Mooney via Flickr | CC BY-ND 2.0

Scientific Name: Nerodia Fasciata
Length: 24-42 inches
Venomous: No

The banded water snake, aka the southern water snake, inhabits the swamps, rivers and lakes in extreme southern Alabama. They’re a very common species throughout Louisiana, Florida, and north along the coastal plain into the Carolinas.

They are known to sometimes interbreed with midland water snakes. Although they are harmless and non-venomous, they have a wide, flat head and dark coloration which makes them look very similar to a cottonmouth, a species with which they often share habitat.

Like the midland water snake, the banded water snake favors frogs and fish for prey. Banded water snakes can sometimes behave aggressively, counting on their venomous appearance to deter potential predators. This aggressive behavior is likely the source of the many myths about cottonmouth snakes, which actually tend to be quite reclusive.


3. Brown Water Snake

brown water snake | image by BirdPhotos.com via Wikimedia Commons | CC BY 3.0

Scientific Name: Nerodia taxispilota
Length: 30-60 inches
Venomous: No

Brown Water Snakes are one of the larger species of water snakes in Alabama, but are only found in the southeast corner of the state. They prefer large rivers where they can hunt catfish, their favorite prey. This species is a heavy-bodied snake with dark brown colors. This, much like the banded and midland water snakes, makes them look very similar to the cottonmouth and other venomous snakes.

Brown water snakes often prefer to bask on tree branches over the water rather than on the ground, so they’re a common sight in trees along the riverbank. This habit means that they often end up in people’s boats, as startled snakes try to jump straight from the branch into the water. They aren’t venomous, but they will bite to defend themselves and they have many very sharp teeth.


4. Plain-bellied Water Snake

red-bellied water snake | image by Ryan Somma via Flickr | CC BY-SA 2.0

Scientific Name: Nerodia erythrogaster
Length: 24-40 inches
Venomous: No

Plain-bellied water snakes are named for their bellies, which, while often red, can also be a very plain color. Nerodia erythrogaster is also known as the red-bellied water snake. These snakes can be heavy-bodied and their bright underbodies make them stand out of other types of water snakes.

These snakes occur in most of Alabama, especially in lakes and swamps but also in rivers. They’re unusual for water snakes in that they will frequently travel long distances over land to a new body of water.

They’re also largely nocturnal, preferring to hunt during the night and spending the whole day basking in the sun. Like other water snakes, they will bite repeatedly to defend themselves, even though they aren’t venomous.


5. Green water snake

Mississippi green water snake | image by Peter Paplanus via Flickr | CC BY 2.0

Scientific Name: Nerodia cyclopion
Length: 30-55 inches
Venomous: No

Green water snakes are only found in Southwestern Alabama. This species is more common in surrounding states in the Southeast like Georgia, Louisiana, Arkansas, Mississippi, and Tennessee. These medium sized snakes are usually dark green or brown in color and have fairly stout bodies.

Green water snakes thrive in the state’s wetlands and prefer large amounts of vegetation in the water. They’re most active during the day and feed on small fish and amphibians. When it comes to green water snakes you have Nerodia cyclopion, which is the Mississippi green water snake, and then you have Nerodia floridana, which is the Florida green water snake. From what I can ascertain, the Florida green water snake is not present or very uncommon in Alabama.


6. Diamondback water snake

diamondback water snake | source: USFWS Midwest Region via Flickr

Scientific Name: Nerodia rhombifer
Length: 3-5 feet

The diamondback water snake is predominantly brown, dark brown or dark olive green, with a black pattern along the back, each spot being diamond-shaped. Their scales are a very rough texture and they typically grow to be about 3-4 feet long, though in some cases bigger. The underside is often a yellow or light brown color.

This snake is often confused for a venomous snake, but like all other water snakes diamondback water snakes are not venomous. They are an aggressive snake though and will release musk and fecal matter if provoked.

They are most common in areas of western and central Alabama. The diamondback water snake enjoys basking on tree limbs above the water and hunting for its prey which includes small amphibians, lizards, mice, etc.


7. Salt marsh snake

saltmarsh snake | image by Scott Beazley via Flickr | CC BY 2.0

Scientific name: Nerodia clarkii
Length: 15-30 inches
Venomous: No

The salt marsh snake has 3 recognized subspecies; the gulf salt marsh snake, the mangrove salt marsh snake, and the Atlantic salt marsh snake. They live in the brackish waters along the coastal regions from Texas to Florida, including southern Alabama near the Gulf Shores coastline. Here they feed on a variety of small fish and invertebrates.

They are rather small in size in comparison to other water snakes in the Nerodia Genus of snakes. Primarily active at night, these saltwater snakes are not seen in freshwater and obtain the water they need from their prey. Because of their limited habitat along the coasts, they are not commonly seen in Alabama unless you live neat the coast.


Bonus: Cottonmouth

source: Alabama Extension via Flickr

Scientific name: Agkistrodon piscivorus
Length: 36-48 inches
Venomous: Yes

When you think of water snakes you likely think of the water moccasin, aka cottonmouth, though they aren’t technically water snakes in the Genus Nerodia. Cottonmouths are infamous, and have an undeserved reputation as aggressive snakes. They never venture far from the water and are often seen swimming, which kind of makes them seem like venomous water snakes. In Alabama you’ll find both the northern and Florida subspecies of cottonmouths.

Water moccasins are dark brown or black on top and the same on their bellies. Younger snakes can have a light pattern on their backs but tend to get darker as they mature. They feed on fish, amphibians, and reptiles just like regular water snakes. Cottonmouths however are highly venomous and a bite should be treated quickly. If you see one or aren’t sure what species it is, when in doubt you should always avoid snakes just to be safe.

About Jesse

My name is Jesse. I've always been interested in reptiles and have owned many different types in my life. On this blog I share some of the things I've learned over the years and am still learning about reptiles.