Summer is here, and it is time to get outside and enjoy the warm weather. Hold on, though! Animals enjoy the summer temperatures too, and some of those heat-lovers are snakes. In Florida, there are quite a few dangerous animals running around, but the venomous snake is one to keep an eye out for. The top four largest (and most dangerous) snakes in Florida are the copperheads, cottonmouths, diamondbacks, and timber rattlesnakes. But which is the biggest, which is the most dangerous, and who is that imposter snake that’s pretending to die? Let us get into it because it is snake season!
The Top Four Largest (And Most Dangerous) Snakes In Florida
For this list, we are going for size first, and dangerous venom second. But do not let these snakes from the Sunshine State fool you, size does not always dictate how dangerous they are! In fact, the largest venomous snake in Florida even has a lookalike that is not even venomous. This imposter snake is so good at acting like a dangerous species that some call it the “Prima Donna” of the snake world!
4. The Eastern/Southern Copperhead

The copperhead is the fourth largest snake found in Florida, but it’s venom is not deadly. However, it is painful and copperheads are notoriously aggressive!
©Jay Ondreicka/Shutterstock.com
Size | 24-36 inches long |
Habitat | Rocky areas, high elevations, marshes |
Venom | Extremely painful but not deadly, risk of infection |
Behavior | Extremely aggressive, strikes with no warning, blends well with surroundings |
The copperhead is named for its overall reddish-brown coloring and can be identified by the brown hourglass markings over the body. Copperheads are pit vipers, with characteristic triangular heads and slitted, catlike pupils. This species is nocturnal but is significantly more active in the fall and spring. Due to its unique color and pattern, the copperhead is a master of camouflaging itself. In Florida, this species is only found in the Panhandle region.
3. The Cottonmouth (Water Moccasin)

The Cottonmouth is the third largest Florida snake, but it is one of the most deadly, with venom that will kill a human without prompt medical care!
©KF2017/Shutterstock.com
Size | 20-48 inches long |
Habitat | Swamps, marshlands, any location with standing water |
Venom | Deadly without medical attention |
Behavior | Moderately aggressive, raises and tilts head back and opens mouth wide to reveal white “cotton colored” interior as a warning. |
The cottonmouth can be identified by its reddish-brown coloring with black banding when it is young but may darken to grey or black with age. This species also has a spade-shaped head, unlike other species of water moccasins. Cottonmouths are found throughout the state of Florida, along with multiple water moccasin lookalikes.
However, as the cottonmouth is particularly aggressive, one should not waste time identifying them!
2. The Timber Rattlesnake

The timber
rattlesnake
is the second largest snake in Florida, but it is considered a rare sight. Which is a good thing, because this snake has the deadliest venom of all United States vipers!
©Frode Jacobsen/Shutterstock.com
Size | 36-60 inches long |
Habitat | Forests, farms, agricultural areas, lowlands |
Venom | Most concentrated venom of any U.S. snake, deadly without prompt medical attention |
Behavior | Ambush hunter with a little warning prior to striking. Running is advised as this snake is docile and not prone to aggression. |
Timber rattlesnakes are a yellowish-grey color over the body with brown or black arrow-shaped markings and one long reddish-brown stripe down the whole body. This pit viper is docile and is more prone to stay still and wait for you to leave than strike. However, remember what we said about this snake’s venom!
While this is the second-largest snake found in Florida, it is a rare snake to see in this state. When spotted, it is more common in northern Florida.
1. The Southern/Eastern Diamondback

The Eastern Diamondback is the largest venomous snake in both Florida and the entire United States.
©Chase D’animulls/Shutterstock.com
Size | 36-72 inches long |
Habitat | Dry areas, scrub, bushes, woodpiles, and occasionally near water |
Venom | Deadly without prompt medical attention |
Behavior | Mildly aggressive, lifts head slowly in warning along with rattle, strikes very quickly from up to four feet |
The largest (and most dangerous) snake in Florida is the southern/eastern diamondback rattlesnake which is brown with a signature darker brown diamond pattern bordered in yellow down the back. This species can also be identified by its distinct black face markings. The diamondback is found throughout all of Florida and is the largest venomous snake in the United States. Due to its sheer speed and impressive striking distance, it is also considered the deadliest. Thankfully, the diamondback gives you plenty of warning beforehand, and backing away slowly will save you that deadly bite!
The Diamondback Imposter: The Eastern Hognose

The Eastern Hognose is great at impersonating the Diamondback, but this snake isn’t venomous!
©iStock.com/JasonOndreicka
The eastern hognosed snake’s evolutionary claim to fame is simple. It evolved to look like one of the deadliest venomous snakes in the United States! This great imposter is often mistaken for the diamondback rattlesnake, due to its yellow and brown markings. But while any snake bite will hurt, the eastern hognose has no venom. The hognose species of snakes are easy to identify by their narrow heads and upturned and pointed “hoglike” snouts.
This species is well-known for its theatrics as well! From flattening their heads to look like cobras or pretending to be dead to deter predators, they will do anything to mimic a dangerous snake. They are not deadly, but they sure are entertaining!
Summary Of The Top Four Largest (And Most Dangerous) Snakes In Florida
Rank | Snake | Size | Venom |
---|---|---|---|
1 | Eastern/Southern Copperhead | 24-36 inches long | Extremely painful but not deadly, risk of infection |
2 | Cottonmouth (Water Moccasin) | 20-48 inches long | Deadly without medical attention |
3 | Timber Rattlesnake | 36-60 inches long | Most concentrated venom of any U.S. snake, deadly without prompt medical attention |
4 | Southern/Eastern Diamondback | 36-72 inches long | Deadly without prompt medical attention |
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