Tennessee’s Largest, Most Dangerous Snakes

Tennessee is a state that rewards outdoor activity—until you stumble upon one of its venomous, dangerous snakes. The good news is that this state’s limited roster of reptiles inspires more fear than actual risk, which is why taking the time to fully understand them may help you feel better about exploring this locale. What are Tennessee’s largest, most dangerous snakes, and how can you best keep yourself safe if you encounter one?

According to the Tennessee Wildlife Resources Agency (TWRA), Tennessee is home to approximately 32 to 35 native snake species, depending on subspecies. Of that already limited number, only four snakes are considered medically significant (AKA dangerous) to humans. Knowing what those four snakes look like and where they live is essential knowledge for anyone spending time outdoors in Tennessee, and we’re here to help.

Here is what you need to know about each of Tennessee’s four venomous species, plus a special look at the state’s largest, but surprisingly harmless, snake.

1. The Timber Rattlesnake

If there was a single snake worth avoiding in Tennessee, it’s the timber rattlesnake. The state’s wildlife agency wrote that “the Timber Rattlesnake is the largest and most dangerous of the 4 venomous snakes in Tennessee.” For anyone interested in spending time in the state’s forests or rural areas, this is the snake that demands the most respect and proper identification.

What it looks like: The timber rattlesnake typically measures between 36 and 60 inches in length, and it has a broad, triangular head, vertical pupils, keeled scales, and a rattle at the end of its tail. It’s important to note that the body color of this snake is highly variable. In Tennessee, it’s usually gray with a black tail, though colors can include yellow, tan, brown, pink, dark brown, or almost entirely black, with chevron-shaped crossbands and a rust-colored stripe.

Where it lives: Unlike some of Tennessee’s other venomous species, the timber rattlesnake is unfortunately found statewide. It is often associated with bluffs or ledges, and can also be found around mountains, swamps, cane thickets, wooded stream corridors, and rural habitats.

What makes it so dangerous: While it’s said to have one of the most potent bites of any venomous snake in North America, the timber rattlesnake is also described as shy and reclusive, giving ample warning with its rattle before it attempts to strike. Deaths from its bite are extremely rare, but it is a snake that easily surprises people when woodpiles are moved or when these snakes are caught sunning at inopportune times.

2. The Copperhead

While timber rattlesnakes are the most dangerous snakes in Tennessee because of their venom, the snake responsible for the most bites in Tennessee is the copperhead. It is also found across the entire state, thriving in both rural and suburban environments, and blending into leaf litter so effectively that many bites happen unnoticed.

What it looks like: Measuring 24 to 36 inches, copperheads have a distinctive, large, triangular-shaped, coppery-red head and vertical pupils. They also have dark brown hourglass crossbands that are wide on the sides and narrow at the center of the back. Young copperheads have a bright yellow tail tip, while adults do not.

Where it lives: Copperheads are remarkably adaptable, turning up in just about every environment in the state, including suburban backyards and rural areas. However, they prefer to be covered for their own safety, which is why they are most often encountered when moving through undisturbed areas.

What makes it dangerous: The Copperhead’s venom isn’t nearly as potent as the timber rattlesnake, with very few deaths attributed to it. However, it is responsible for more snake bites in Tennessee than any other species, and nationwide accounts for roughly 30% of all snake bites in the United States.

3. The Cottonmouth

Also known as a water moccasin, the cottonmouth has one of the most fearsome reputations of any snake in the American South and Tennessee, even if it doesn’t reside in the entire state. For example, if you’re hiking in East Tennessee, you will not encounter one of these snakes (though the others are likely to be lurking nearby).

What it looks like: This large pit viper reaches an average of 30 to 42 inches in length, with dark olive-brown to almost black coloration. It also has dark crossbands that may not be clearly visible, and the top of the head is dark brown or black, with a wide, dark band running from the snout through the eye. Its most famous identifying feature is the bright white lining of its open mouth, giving the species its common name.

Where it lives: Cottonmouths are the most aquatic of Tennessee’s venomous snakes, so they are often found swimming in or lounging beside water. The Reelfoot Lake region is among the most well-known areas of cottonmouth habitat in the state, so keep this in mind if you’re planning a visit.

What makes it dangerous: A cottonmouth bite can cause temporary or even permanent tissue damage, internal bleeding, and extreme pain, though fatalities remain rare. Any bite should be treated as a medical emergency, and this snake is primarily dangerous due to its ample presence around water in summertime.

4. The Western Pygmy Rattlesnake

A small and colorful snake, the western pygmy rattlesnake is found only in a narrow strip of the state and is actually listed as a threatened species. It is often noted as the smallest and one of the least-known venomous snakes in Tennessee, but that doesn’t mean you won’t encounter it.

What it looks like: Growing only 15 to 20 inches in length, this rattlesnake has a thin tail, complete with a tiny rattle. It is often gray or tan with an orangish-brown mid-dorsal stripe, and dark bar-shaped blotches running the length of the back. The rattle is also unique and can be confusing, sounding more like a buzzing insect as you get closer.

Where it lives: The range of this snake is limited to the western Highland Rim, running from Stewart County south to the state’s border with Mississippi and Alabama. Like the cottonmouth, it is typically found near water, in floodplains, marshes, wetlands, woods, and glades, as it can indeed swim.

What makes it dangerous: This snake can pose a greater risk to children and small pets, especially since it often hides in plain sight. Both its small size and nearly inaudible rattle make surprise encounters more likely than with the larger timber rattlesnake, as you often can’t hear it until you’re right on top of it.

5. The Gray Ratsnake: Tennessee’s Largest Snake (and One of Its Least Dangerous)

While not a danger, the gray ratsnake is described by TWRA as one of the most abundant snakes in the state, found in every corner of Tennessee and growing to incredibly long lengths. It is, by size, Tennessee’s largest snake, though it is far from the most dangerous.

What it looks like: This is undoubtedly a large snake, averaging anywhere from 42 to 72 inches in length. Adults are typically black or very dark gray, often with bits of white visible between their scales and a lighter throat.

Young ratsnakes look strikingly different from adults, often resembling copperheads. This is why these completely harmless snakes are often killed by people who mistake them for a far more dangerous species. However, it doesn’t help itself in this regard, as it can mimic the rattle of rattlesnakes in an effort to ward people away.

Where it lives: There are very few places a ratsnake won’t live. If you’ve spotted a large, dark snake climbing a tree, exploring your attic, slithering along a woodland trail, or curled up in a barn in Tennessee, it was almost certainly this harmless reptile.

What to Do If You Encounter a Venomous Snake in Tennessee

The single most consistent piece of advice from any and all snake experts, regardless of state or type of snake, is this: leave it alone.

This advice applies whether you’re on a trail or in your own backyard: data from the Tennessee Herpetological Society shows that the vast majority of bites happen when someone is attempting to handle, harass, or kill a snake, often on their own property. Under Tennessee state law, it is generally illegal to harm, capture, or kill native snake species, including venomous ones, except when a snake poses an immediate threat to human safety or livestock.

If you are bitten by a venomous snake in Tennessee, remain calm, move away from the snake, do not attempt to capture or kill it, and always, always call 911 immediately. A photograph of the snake taken from a safe distance can help medical staff identify the snake, but it is not required.

Why is that? Technically, because all four of Tennessee’s venomous snakes are pit vipers, the antivenom used is the same for all of them. After calling 911, never apply a tourniquet or try to suck out the venom, which is a common misconception. Additionally, don’t apply ice despite the likely pain, and avoid giving the bite victim food or alcohol.

Finally, if you need help identifying a snake on your property, TWRA encourages residents to photograph it from a safe distance and reach out to the agency via email at [email protected] or through their Facebook page for identification assistance. An identified snake is a safer snake, and it makes for a much safer household in the long run.

Stay Safe From Snakes in Tennessee

Tennessee’s venomous snakes may sound scary, but this state receives approximately 50 bites annually, not even ranking among the top five states for snakebite fatality risk. The snakes that live here are part of a functioning ecosystem, controlling rodent populations and providing prey for other wildlife, much like they do in every other state.

Recognizing and understanding these four venomous species, along with the state’s largest nonvenomous species, is the best way to protect yourself—using knowledge instead of weapons. Your knowledge makes the difference between a safe outing in Tennessee’s wilderness and a dangerous one, both for you and the snakes that also call this state home.