These Are the Snakes You’ll Find in the Arkansas River

Arkansas is home to 39 species of snakes, and six of them are venomous. Thankfully, not all of these venomous snakes inhabit Arkansas’ waterways. Of those 39 species, only about seven snakes are commonly seen in water, such as those found in the Arkansas River. Many of these are harmless, but some can be aggressive—here’s what you should know about them before swimming.

Yellow-Bellied Water Snake

The yellow-bellied water snake, Nerodia erythrogaster, is a non-venomous snake found in Arkansas rivers. This species is challenging to identify due to its variable patterns, which change as it matures. Juvenile yellow-bellied water snakes have a checkered pattern with alternating dark brown and tan colors. Adult yellow-bellied water snakes are darker, usually appearing as a solid shade of dark brown, green, or gray, with a yellow underbelly. When fully grown, they can reach a length of up to 48 inches.

This snake isn’t picky about its aquatic environment. It can be found during the daytime near lakes, ponds, streams, rivers, and even drainage ditches. The only place they’re not seen, according to Herps of Arkansas, is in north central Arkansas. Yellow-bellied water snakes also hang from trees or vines over water, so it’s essential to keep an eye on low-hanging branches. While it’s non-venomous, it will drop down into the water when spooked. They’re primarily active during the summer and after high rainfall, drawn particularly to flooded areas.

Black Rat Snakes

Black rat snakes, Pantherophis obsoletus, are common in Arkansas. They camouflage exceptionally well thanks to their coloring. Mature snakes are black with a cream-colored underbelly, and can grow up to seven feet long. Due to their size, rat snakes are constantly searching for food and are also avid sunbathers. While it’s sometimes debated, the black rat snake is one of the most common snake species found in Arkansas.

While not exclusively drawn to water, black rat snakes follow the path of their next meal. This means rivers, streams, and lakes are potential hunting areas, especially anywhere prey might stop for a drink. They’re also found around barns, chicken coops, and brush piles, since they hunt rodents. Black rat snakes are also known to coil up on high tree branches or in hollows, so exercise caution when hiking near waterways. As a species, they’re relatively docile and are not prone to attacking humans.

Speckled Kingsnake

The speckled kingsnake, Lampropeltis holbrooki, is relatively easy to identify. As the name implies, this snake is black with pale yellow speckles throughout its upper body, with a yellow underbelly. As the snake matures, the speckles become more checkered. These snakes can grow up to 48 inches long once fully mature.

Speckled kingsnakes are both foragers and voracious predators. They’re non-venomous and pose more of a threat to other snakes than to humans. They primarily consume rodents, but won’t hesitate to eat another snake, including a venomous one. This species is not known for climbing, but it will scavenge bird nests that are within its reach. Due to its varied diet, it can be found along waterways and near lakes or streams. It’s not likely to bite a human, but it displays an aggressive nature if it senses its next meal.

Midland Water Snake

The midland water snake, Nerodia sipedon pleuralis, is often confused with the venomous cottonmouth. Its banding closely resembles the dark brown and tan stripes of the venomous cottonmouth, making identification difficult. If you are close enough, you can identify this snake by its round eyes and white lower lip, which indicate it is non-venomous. As adults, these snakes can grow to a length of 49 inches.

This snake also shares similar habits with the cottonmouth. It can be found basking in the sun along rivers, lakes, and ponds, and is known to hang from trees. It can be found in practically any body of water, including deep puddles or man-made ponds. As a result, sightings of this snake are frequent but often unpredictable. Reflecting their aquatic nature, midland water snakes primarily hunt turtles, fish, frogs, and crayfish. It can remain submerged for extended periods, especially when hunting, often waiting under rocks or in crevices. While this snake is not naturally aggressive, it’s not a bad idea to check rocky riverbeds before going for a swim.

Broad-Banded Water Snake

The broad-banded water snake, Nerodia fasciata confluens, is often mistaken for a venomous snake. Its striped pattern alternates between tan and black, with bright yellow and red bands on its underbelly. Its head is bright red, which is a definitive marking of the species. When fully mature, it can grow to 30 inches long.

This misunderstood snake is often killed when it’s mistaken for the cottonmouth. Though it’s non-venomous, its defensive behavior mimics that of its venomous counterpart. The fact is that this snake is naturally defensive rather than offensive. It’s more likely to flee and try to escape, only attacking if it’s truly cornered. Because of this, you may not even realize there’s a broad-banded water snake nearby. It prefers marshes and low-lying waterways with plenty of vegetation. This is where it can be found basking during the day, but it will occasionally enter the water and remain at the surface.

Diamondback Water Snake

The diamondback water snake, Nerodia rhombifer rhombifer, is yet another that’s commonly mistaken for a venomous species. The most significant difference between the two is the eyes of the diamondback water snake. This species has distinctly round eyes with a red hue that stands out against its dark banding. Adults can grow up to 48 inches long.

You’re unlikely to run into this snake in the Ozarks or Ouachita Mountains. It prefers low-lying marshes and swamps but can also be found along the Arkansas and White Rivers. Like many other water snake species, it can be seen hanging from low branches or vines. It is primarily active at night and can be elusive during the day, but it is not impossible to spot. However, this snake has a more aggressive temperament than others. Its first instinct is to flee, but it also won’t hesitate to bite if it feels threatened.

Northern Cottonmouth

The northern cottonmouth, Agkistrodon piscivorus, is known by several names, including the water moccasin. As its name implies, this highly venomous species is no stranger to water. Coloring on the cottonmouth varies from snake to snake, making identification challenging. Adults can be black, brown, or dark green, with banding that isn’t always easy to spot. According to Herps of Arkansas, dusty or dirty snakes can be even more difficult to identify. Unlike non-venomous snakes, the eyes of a cottonmouth are hard to see from above. If you can see its eyes, they’ll be slitted and serpent-like, unlike the round eyes of a non-venomous species. Cottonmouths also have brightly-colored tails that are typically green or yellow.

Most cottonmouths are commonly found near water, and many are often seen swimming in it. This makes them a greater threat to humans, especially those swimming in still water. Cottonmouths prefer slow-moving water sources over fast-moving ones and can be found basking in vegetation along the water’s edge. If they are not basking, cottonmouths can be found under rocks, coiled up in roots, or in the deep hollows of a river or lake. Cottonmouths can bite both above and underwater, and should be given a wide berth. As a defense, they’ll often emit a foul odor to warn predators that they’re nearby. They open their mouths as a second line of defense, which means they’re close to striking. They are territorial but typically don’t go after humans; however, they should be respected as a venomous species.