Southeastern United States residents share their habitat with a number of serpents, including water snakes. The most common water snake types in this region include banded water snakes, midland water snakes, and water moccasins. It doesn’t help that they all look incredibly similar, but only the water moccasin is venomous.
Banded and midland water snakes have round pupils that are visible from above. A water moccasin’s eyes have vertical, slit-like pupils and aren’t visible from above. Water moccasins have large, blocky heads distinct from their necks, and white mouths. Banded and midland water snakes have slim heads.
Read on for an in-depth overview of these three water snakes so you can know how to tell them apart.
An Overview: Water Moccasins and Banded and Midland Water Snakes
Water moccasins, banded, and Midland water snakes are so similar in appearance that you either have to be a dedicated outdoor enthusiast or herpetologist (a reptile specialist) to tell these snakes apart.
Let’s take a closer look below at how they differ:
Appearance
All three snake species have similar patterns and coloration, consisting of reddish-brown, gray, tan, and yellow crossbands or botches on their backs.
Adult individuals across these three species also tend to have a uniform black appearance since the colorations fade with age—moreover, water moccasins, Midland, and Banded water snakes all sport stout bodies.
Venom
Only water moccasins are venomous. This means that a bite from a water moccasin will send you to the ER and could even result in death in some instances.
On the other hand, Banded and Midland water snakes are not venomous. Although they can deliver painful bites, that is about the extent of the damage they can inflict.
Consequently, Midland and Banded water snakes are often killed unnecessarily due to being mistaken for water moccasins.
Classification
You might wonder why these snakes look so similar yet belong to different families. Banded and Midland water snakes belong to the same family and genus: Colubridae and Nerodia. In fact, Midland and Banded water snakes can mate and produce offspring, hence why they are so similar in appearance.
In contrast, water moccasins are from an entirely different family of serpents. Water moccasins belong to Viperidae, meaning they are vipers. They are cousins of rattlesnakes and copperheads.
So, why would Banded and Midland water snakes bear such a close resemblance to water moccasins? Experts believe it is an evolutionary adaptation to keep danger at bay. By resembling a fearsome viper, few animals and humans will be willing to tangle with these harmless snakes.
That said, let us look at each of these snakes in closer detail:
Banded Water Snakes
Also known as the Southern or Florida water snake, Banded water snakes (Nerodia fasciata) are endemic to the central and southeastern United States. Even though Florida has the highest population of Banded water snakes, this species has an extensive range, extending from the Carolinas and Georgia to Alabama, Arkansas, Louisiana, Mississippi, and Oklahoma.
California also has banded water snakes. However, they are an invasive species there, meaning they were brought by humans to California for some reason, and left to fend for themselves.
Banded water snakes get their name from the crossbands covering their entire backs. They have red, brown, or tan bands over a grayish body. These bands are pretty distinguishable in snakelets and juveniles. However, they fade with age, explaining why adult banded snakes tend to be uniformly black.
You can also identify a banded water snake by looking for a dark stripe running from the corner of its mouth. Additionally, they have a red tongue with a black tip.
As mentioned, the eyes of banded water snakes have round pupils, a defining characteristic of non-venomous snakes.
Regarding temperament, banded water snakes prefer flight to fight, and would rather run away than engage you. However, when cornered, a banded water snake will try to look as threatening as possible by flattening its head to give it a triangular shape akin to that of a venomous water moccasin. They might also secrete a pungent odor from their anal glands. If all fails, banded water snakes will strike and bite you.
Banded water snakes typically reach lengths of 3.5-feet (106.68 cm). They are also thick-looking.
Midland Water Snakes
Midland water snakes (Nerodia sipedon) are closely related to banded water snakes. Therefore, don’t be surprised to find they share so many similarities.
Like banded water snakes, midland water snakes also sport stout bodies and crossbands across their backs.
However, midland water snakes have significantly fewer crossbands than banded water snakes. Midland water snakes have around 30 crossbands on their bodies. Like banded snakes, midlands also sport reddish-brown colorations on their bands, alternating with distinct spots or blotches near their bellies.
Nevertheless, midland water snakes are significantly smaller than their banded cousins. Midlands reach an average of 30 inches (76 centimeters) when fully grown. That said, you cannot always use size as a reliable parameter when telling these two water snakes apart since an individual’s length depends on age and sex.
Midland water snakes are also averse to confrontations. Like banded water snakes, midland water snakes would rather slither away than fight you. However, they also flatten their heads, release a pungent smell, and may bite when cornered.
Water Moccasins
Let’s now meet the bad boy of the group. Water moccasins (Agkistrodon piscivorus) are more commonly known as cottonmouths but also go by a few other intimidating names:
- Water mambas
- Swamp lions
- Gapers
- Snap jaws
These names are fitting because messing with one of these bad boys often ends in grievous consequences.
Water moccasins are unique in many ways. For starters, they are not only the only semi-aquatic viper species but also the only semi-aquatic venomous snake in the United States. Nevertheless, these snakes aren’t afraid of staying on land either, hence their “water moccasin” moniker, since they are comfortable both on solid ground and in water.
In fact, unlike banded and midland water snakes that rarely leave their watery habitats, water moccasins often venture much further inland.
Water moccasins are stocky serpents. They can measure up to 4 feet (121.92 cm) when fully grown and sport thick, muscular bodies covered by keeled scales. Nonetheless, banded and midland water snakes also have keeled (ridged) scales.
The reason people have issues telling water moccasins and Banded/Midland snakes apart is that they also sport distinct reddish-brown bands on their backs.
Fortunately, you can train yourself to identify a water moccasin easily:
Water Moccasins Have Larger Heads
The first distinct water moccasin feature is their large, blocky heads. A water moccasin’s head is noticeably wider than its neck. In contrast, the heads of both banded and midland water snakes are about the same width as their necks.
That is why they tend to flatten their heads when threatened, as doing that allows them to mimic a moccasin’s large head. However, despite the flattening, there will still be no discernible difference between the widths of their heads and necks.
Water Moccasins Have Cat-Like Eyes
Water moccasins also look like the dangerous animal they are. Their eyes have oval or elliptical-shaped pupils, and are slit-like like a cat’s pupils. This is a stark contrast to the round pupils of midland and banded water snakes.
Additionally, you cannot see a water moccasin’s eyes when you are standing directly above it, whereas you can see those of banded and midland water snakes.
Water Moccasins Have Sensory Pits
As mentioned, water moccasins are vipers. As such, they also have heat-sensing pits between their eyes and nostrils. Water moccasins use these pits to detect body temperature, allowing them to track down their prey more effectively.
On the other hand, banded and midland water snakes do not have sensory pits between their eyes and nostrils. Of course, you would need to be literally in the snake’s face to make out these pits, making it an incredibly dangerous identification technique.
Water Moccasins Have All-White Mouths
Water moccasins are also known as cottonmouths for a reason; the inside of their mouths is all-white!
Fortunately, water moccasins are thoughtful enough to remind you of who they are, as they almost always open their mouths to reveal the white interior when threatened.
Water Moccasins Are Venomous
As mentioned earlier, water moccasins are venomous serpents. Their venom has hemotoxin, a compound that prevents blood from clotting, leading to hemorrhaging in the bitten area. If bitten by a cottonmouth, you will need medical attention as soon as possible. A water moccasin’s venom can result in tissue damage, loss of limbs, and even death.
That said, water moccasins are not the devil incarnate most people make them out to be. Water moccasins are not aggressive; they won’t bite without provocation. They will give you many warning signals, including exposing their white mouths, coiling into an S-shape, shaking their tails like a rattlesnake, and secreting a foul odor before striking at you.
Conclusion
Banded water snakes, midland water snakes, and water moccasins are often mistaken for one another, resulting in senseless killings. However, that doesn’t mean that water moccasins deserve to die simply because they are venomous. Please be wary of your surroundings and give the snake its space to avoid unnecessary confrontations.
I hope this guide has been insightful in helping you differentiate these beautiful water snakes.