The 28 Snakes in Iowa (Which Ones Are Venomous?)

A state famous for its prairies and cornfields, it’s easy to believe that Iowa makes a good home for snakes. Indeed, Iowa is home to 28 species of snakes. Furthermore, the vast majority of these snakes, including the most common ones, are nonvenomous and safe for humans to handle, which means that they may make good pets!

However, even though Iowa is only home to four species of venomous snakes, each is capable of injuring or killing someone with a well-timed bite. Does this mean that the Iowa outdoors is impossible to enjoy? Of course not! Luckily, these venomous snakes are not only rare but also often quite shy as well. With this list, we hope to educate readers about the many wonderful snakes that live in the Hawkeye State, as well as how to identify and protect themselves from the more dangerous ones. So, let’s learn about the venomous snakes in Iowa!

Timber Rattlesnake

The most populous venomous snake in Iowa, the timber rattlesnake, is a common sight throughout the United States. They tend to make their homes in the forest of eastern and southern Iowa, though females may migrate to rockier, cooler areas while pregnant. Even though they are more common than other snakes, they still prefer to avoid people (and other predators) altogether, so they will stick to trees, undergrowth, and rocky crevices to avoid detection.

Timber rattlers are easy to identify by their yellow-brown or gray bodies, dark blotches, triangular heads, slit-shaped pupils, and light-colored rattles on black tails. They also have a colored stripe running down their backs, similar to a garter snake. Timber rattlesnakes are also the largest venomous snakes in Iowa, reaching an impressive six feet in length. There are reports of some living to be 30 years old in captivity, but in the wild, it’s more common for them to reach an age of about 10 years. If you are ever traversing the forested wilds of Iowa and hear their iconic rattle, it means you may have wandered into their territory by mistake. Listen for the rattle, then go the opposite way; you do not want to be bitten by any of Iowa’s rattlesnakes, least of all the timber.

Massasauga Rattlesnake

In Iowa, there are two types of massasauga you may encounter: the western massasauga and the eastern massasauga. The western massasauga sticks to the rocky areas of southwestern Iowa, while the eastern massasauga prefers the marshes. Both snakes are quite rare in the wild. This is due to not only their shy nature but also human-induced habitat loss. Both typically have gray bodies, dark blotches, triangular heads, and slit-shaped pupils, though some eastern massasaugas may be brown. The western massasauga is the larger of the two at 39 inches, while the eastern massasauga can reach 30 inches. Though they prefer to eat small mammals, they will also take small amphibians and lizards if they have the chance.

As mentioned earlier, the massasauga is quite shy and would prefer to scare off aggressors with its rattle. In fact, most massasaugas will turn tail and flee before they try to attack. However, if backed into a corner, they are capable of delivering a deadly bite of venom, which is just as deadly as that of other rattlesnakes. That being said, both types of massasauga are becoming increasingly rare encounters for hikers across Iowa, and as long as hikers don’t openly antagonize the snakes, they have little to fear.

Prairie Rattlesnake

True to its name, the prairie rattlesnake makes its home in the grasslands of western Iowa, particularly along the Missouri River. Here, it can catch plenty of its preferred prey of rabbits, prairie dogs, and other small mammals. They can reach the age of 20+ years in captivity and live for 16 to 20 years in the wild. Some distinguishing features are brown spots across its body and two lines on each side of its head. They also come in a variety of colors, including green, brown, and tan. They often grow to be three feet or longer, with the biggest ever recorded being 4.97 feet long.

The prairie rattlesnake certainly isn’t the most common snake in Iowa. On top of having a habitat limited to the prairies of the Loess Hills, they are also an endangered species. If you are traversing this area, keep an ear open for rattles. Unless you happen to be a small rodent, they typically won’t bother you unless you bother them.

Copperhead

A common venomous snake throughout the United States, the copperhead is considered an endangered species in Iowa, but this is mostly because the state lies just barely within its range. If you encounter a copperhead in Iowa, it will likely be in the southeastern corner of the state. However, it would still be foolish to underestimate them as they can inflict a serious bite. They can be found in several types of areas, including forests and grasslands.

Due to their tan or copper coloring, they can sometimes blend into their environments, so keep an eye out for their dark blotches, triangular heads (unlike the fox snake’s narrower head), and a length of two to three feet. They prey on a variety of animals, including rodents.

Other Snakes in Iowa

Let’s also explore some of the most common snakes you’ll find across Iowa. Each of these is non-venomous.

Common Garter Snake

With its iconic dark body and yellow stripe, this species of garter snake is the most common throughout Iowa, as well as many other states. Despite not being venomous, garter snakes can still bite if handled, or they sometimes release a foul-smelling musk. Common garter snakes tend to be on the smaller side, growing to be three or four feet, though some have been known to reach five feet. They are peaceful creatures, and they are active during the day rather than at night. They are often found close to water and prey on animals such as fish, worms, and amphibians.

Western Fox Snake

The western fox snake is named for the very smelly musk it emits that smells similar to that of a fox. Despite being a common sight in Iowa, the western fox snake is endangered in some states. The western fox snake ranges in color from light brown to tan, with dark-colored markings. They may sometimes be mistaken for copperheads, but if you need to differentiate the two then just look at their heads. The copperhead will have a wide, triangular head with eyes like a cat. However, the fox snake has a narrower head and round pupils. That being said, if you’re unsure, it’s safer to assume the worst and steer clear of it.

Western fox snakes are quite large snakes and can reach around five feet long. They are found in a variety of environments, including gardens, fields, and wetlands, and they are capable of climbing and swimming. Their favorite prey includes small birds, amphibians, and eggs.

Brown Snake

At just 13 inches, the brown snake is the smallest snake on this list and poses no threat to humans. They are widespread around Iowa and are a common sight in urban areas such as parks, ponds, and yards, as well as more wild areas like prairies and wetlands. Though usually brown, some will be colored gray, and most have a row or two of dark spots on their backs. They prey on small animals, such as worms and snails.

Smooth Earth Snake

Smooth earth snakes only measure about seven to nine inches long and are often mistaken for worms. They are brown to fawn colored with a lighter colored belly. These non-venomous snakes are reclusive and difficult to observe. They are found under rocks and logs, in loose soil and compost, and under debris in and around gardens. Being so small and with few defenses, smooth earth snakes tend to choose flight over fight when confronted. Gentleness is needed when handling these delicate little snakes, as they are much more fragile than most reptiles.

You can find smooth earth snakes in the same places you find earthworms and slugs: in the dirt and under rocks. Fossorial snakes like these spend most of their time underground sheltering from the sun or hunting. This docile little snake isn’t seen much during the day but is often seen hunting at night when snails, slugs, and earthworms are active.

A Complete List of 28 Snakes in Iowa

Below you’ll find a complete list of the 28 snakes found in Iowa:

• Western Massasauga
• Eastern Massasauga
• Timber Rattlesnake
• Prairie Rattlesnake
• Eastern Copperhead
• Lined Snake
• Smooth Earth Snake
• Western Ribbon Snake
• Plains Garter Snake
• Common Garter Snake
• Brown Snake
• Redbelly Snake
• Graham’s Crayfish Snake
• Western Rat Snake
• Gopher Snake
• Western Fox Snake
• Plain-belly Water Snake
• Smooth Green Snake
• Northern Water Snake
• Diamondback Water Snake
• Eastern Hognosed Snake
• Eastern Milk Snake
• Prairie Kingsnake
• Speckled Kingsnake
• Plains Hognose Snake
• Western Worm Snake
• North American Racer
• Ringneck Snake