15 types of Reptiles found in Wisconsin (2023)
Are you wondering what reptiles you can find in Wisconsin?
This is a great question! Although these reptiles are widespread, they can be difficult to find. Most reptiles, including snakes, turtles, and lizards, are secretive and shy. But observing and finding reptiles is a really fun experience!
Below you will find a list of the most common and interesting reptiles that live in Wisconsin. In addition, you will find detailed pictures, along with range maps for each species to help with your identification!
15 COMMON Reptiles in Wisconsin:
#1. Timber Rattlesnake
- Crotalus horridus
- Adults typically range from 30 to 60 inches in length.
- Coloration is variable and generally ranges from yellowish-brown to gray to almost black. Look for dark brown or black crossbands on their back.
- Heavy-bodied with a characteristic rattle on the tail.
The Timber Rattlesnake, also known as the Canebrake Rattlesnake, is found in various habitats. Look for these venomous reptiles in lowland thickets, high areas around rivers and flood plains, agricultural areas, deciduous forests, and coniferous forests.
Timber Rattlesnake Range Map
Credit: Virginia Herpetological Society
These snakes are ambush predators, waiting for unsuspecting prey to come within their strike range. They feed primarily on small mammals but may also consume frogs, birds, and other smaller reptiles. Timber Rattlesnakes strike their prey and release them, waiting until their venom has taken effect before eating them.
These venomous snakes are potentially the most dangerous reptile in southwestern Wisconsin due to their large size, long fangs, and high venom yield. Luckily, Timber Rattlesnakes have a mild disposition and don’t bite often. Additionally, they typically give plenty of warning by rattling and posturing.
The Timber Rattlesnake played a noteworthy role in U.S. history. Found in the original 13 colonies, it was used as a symbol during the American Revolution. In 1775 it was featured at the center of the “Gadsden Flag.” This yellow flag depicts a coiled and ready-to-strike Timber Rattlesnake and the words “Don’t Tread on Me.”
#2. Northern Watersnake
- Nerodia sipedon sipedon
- Adults range from 24 to 55 inches in length.
- Coloration is pale grey to dark brown with reddish-brown to black bands.
- Large adults become darker with age and appear almost plain black or dark brown.
- Females tend to be larger than males, and coloration is most vivid in juvenile and wet individuals.
Northern Watersnakes are one of the most common reptiles in Wisconsin!
Northern Watersnakes prefer slow-moving or standing water like ponds, lakes, vernal pools, marshes, and slow-moving rivers and streams. They’re often seen basking on rocks or logs in or near the water.
Northern Watersnake Range Map (Yellow area below)
Credit: Virginia Herpetological Society
These reptiles primarily feed on fish and amphibians by hunting along the water’s edge and shallow water during the day. They grab their prey and quickly swallow while it’s still alive!
While non-venomous, they can deliver a painful bite!
Their saliva contains a mild anticoagulant that can cause bites to bleed, making the injury appear worse. These important defense mechanisms help water snakes survive predators such as raccoons, snapping turtles, foxes, opossums, other snakes, and birds of prey.
#3. Eastern Garter Snake
- Thamnophis sirtalis sirtalis
- Adults typically range from 18 to 26 inches in length.
- Coloration varies and can be mixtures of green, brown, or black. Look for a distinct yellow or whitish stripe down the center of their back.
- Some individuals may exhibit a checkered body pattern.
- Subspecies of the Common Garter Snake.
Eastern Garter Snakes are a very common reptile in Wisconsin!
In fact, they are typically the snake species that people come across the most. They’re well-adapted to living around people and can often be found in city parks, farmland, cemeteries, and suburban lawns and gardens. Though not required, they prefer grassy environments near freshwater sources such as ponds, lakes, ditches, and streams.
Look for these reptiles in Wisconsin basking in the sun in grassy areas near cover.
Eastern Garter Snakes protect themselves when they are cornered or feel threatened. For example, if you disturb one, it will defecate and release a foul-smelling musk from its glands. It’s also common for them to bite as a last resort!
The Eastern Garter Snake most commonly preys on toads, frogs, slugs, salamanders, fish, and worms. However, they are very opportunistic and will eat other insects and small animals they can overpower.
- RELATED: 16 COMMON Amphibians in Wisconsin!
#4. Plains Garter Snake
- Thamnophis radix
- Adults average 36 inches in length.
- The coloration is gray-green with a distinctive orange stripe down the back and a greenish-yellow stripe down each side.
- Distinct light yellow spots on the very top of the head!
Plains Garter Snakes live near freshwater sources. They have a fairly large population and adapt well to human-modified landscapes. You may spot them near abandoned buildings, trash heaps, or vacant lots.
This species is considered one of the most cold-tolerant of all reptiles! They will even come out of hibernation on warmer winter days.
Plains Garter Snakes feed primarily on earthworms, slugs, and small amphibians. However, they have also been observed preying on small mammals and birds.
#5. Eastern Milksnake
- Lampropeltis triangulum triangulum
- Adults typically range from 24 to 36 inches in length.
- Coloration is tan or gray with 3 to 5 rows of reddish-brown, black-edged blotches.
- Look for a gray or tan Y- or V-shaped mark near the rear of the head.
Eastern Milksnakes get their unique name from an old myth that they milked cows since they’re commonly found in barns! Obviously, this isn’t true. Instead, their presence inside barns is likely due to the high number of mice, some of their favorite prey.
Eastern Milksnake Range Map
Eastern Milksnakes occupy various habitats, including fields, woodlands, agricultural areas, and rocky outcrops. Like other reptiles in southern Wisconsin, these beautiful snakes are secretive and spend much of their time beneath the ground. However, you may be able to find one underneath rocks, logs, boards, and other debris.
The Eastern Milksnake prefers to feed on small mammals like mice and shrews. However, they’ll also consume various types of prey, including birds and bird eggs, lizards, snakes, amphibians, fish, earthworms, slugs, insects, and carrion.
Like other individuals in the kingsnake family, they will prey on venomous pit vipers. Their blood contains venom-neutralizing properties!
#6. Gray Ratsnake
- Pantherophis spiloides
- Adults range from 42 to 72 inches in length though individuals up to 101 inches have been recorded.
- Coloration varies. Most Gray Ratsnakes are typically completely black.
- There may be red, white, or yellow flecking on the scales.
Unlike many reptiles in Wisconsin, Gray Ratsnakes are most at home in trees!
They are excellent climbers and often hunt and spend time in trees. Growing up, I used to see them in a large walnut tree in our backyard!
They’re also spotted near barns and old buildings since these places provide them access to their favorite food, rodents. This species is an active hunter and a powerful constrictor. They suffocate larger prey using their strong coils but often swallow smaller prey immediately.
If disturbed, Gray Ratsnakes either flee for cover or remain motionless in an attempt to avoid detection using their excellent camouflage. In dry leaf litter, they may also vibrate their tail, producing a rattlesnake-like sound. Finally, when they feel cornered or are grabbed, these reptiles will strike their attacker as a last resort.
#7. Eastern Hog-nosed Snake
- Heterodon platirhinos
- Adults typically range from 20 to 30 inches in length.
- Coloration can be yellow, gray, brown, black, olive, or orange, often with darker blotches or spots down its side and back, though solid gray and black individuals are fairly common.
- They have thick bodies, broad, triangle-shaped heads, and an upturned snout.
Eastern Hog-nosed Snakes primarily prey on toads. They have enlarged teeth at the rear of the upper jaw to puncture and deflate toads that puff up when threatened. These reptiles also have large adrenal glands, which secrete hormones to counteract the toad’s potent skin poison!
When disturbed, Eastern Hog-nosed Snakes lift their head off the ground and flatten their neck like a cobra! They may also hiss and display a false strike.
If this display fails to scare off a predator, the snake will play dead. They’ll roll onto their back, let their tongue hang out, and emit musk from glands near the base of their tail. Interestingly, when the threat has left, the snake will right itself and continue as normal. 🙂
#8. Dekay’s Brownsnake
- Adults typically range from 6 to 13 inches in length.
- Coloration is light brown or gray to dark brown or black with two rows of dark spots down the back, sometimes linked.
- They have a dark streak down the head and may have a light stripe down the center of the back.
Dekay’s Brownsnakes occupy various terrestrial habitats as long as there’s plenty of cover available such as rocks, logs, boards, and trash and organic debris. As a result, they’re often found in backyards and gardens under objects.
These secretive, nocturnal reptiles hunt during the evening and night, feeding primarily on slugs and earthworms. They typically grab and quickly swallow their prey alive.
These docile reptiles usually don’t bite in defense. Instead, if captured, they often squirm vigorously or flatten their bodies and may release foul-smelling musk.
This species is considered common in most of its range and is not a major conservation concern. It adapts well to human development and has a reputation as a “city snake.”
#9. Six-Lined Racerunner
- Aspidoscelis sexlineata
- 2.25 to 3.75 inches long from snout to vent (length does not include the tail).
- “Dark fields,” or broad stripes in between lighter stripes on whiptails, are brown to black.
- 6-8 light stripes vary in color from white or yellow to gray-blue.
- The coloring is much brighter in males, with greens on the back and light turquoise on the belly.
This reptile is easy-to-spot in southwestern Wisconsin.
Six-Lined Racerunners are insectivores, and their primary food source is termites. However, they also eat beetles, ants, and spiders, so these small whiptails can be handy if you have a pest problem.
The Six-Lined Racerunner lives up to its name, clocking speeds up to 18 miles per hour! They have no problem outmaneuvering predators and curious humans!
#10. Common Five-Lined Skink
- Plestiodon fasciatus
- Adults are up to 8.75 inches long.
- Five stripes are most apparent in hatchlings and fade as the skinks grow.
- Males have orange-red coloring on the jaw during the breeding season.
- Hatchlings are black with light stripes. The black coloring often fades to gray, and the lighter stripes darken.
Look for Common Five-Lined Skinks in wooded areas near cover objects. Their diet consists of spiders, beetles, crickets, and other insects.
Credit: Virginia Herpetological Society
Females attend to their eggs throughout the incubation period. They spend almost all of their time defending the eggs until they hatch!
If you come across a nest, you may notice the mother curled up on top of or around the eggs. She also rolls the eggs to maintain their humidity, moves them back to the nest if they become disturbed, and even eats eggs that aren’t viable!
#11. Slender Glass Lizard
- Ophisaurus attenuatus
- 22 to 47 inches long.
- Coloring is generally brown to black, with whitish markings in the middle of the scales.
- Younger individuals have dark stripes along the back and sides, and older individuals develop faint crossbands.
Comparing them to other reptiles in Wisconsin, Slender Glass Lizards look more like snakes.
However, unlike snakes, they don’t have flexible jaws, which means they can only eat prey smaller than their head! Prey includes insects, spiders, small rodents, and reptiles.
United States Geological Survey (USGS)
Glass lizards are named for their extremely fragile tails, which can break off even without being touched. If you notice that the end of its tail is tan with no stripes, you can be sure the lizard lost its original tail.
There are two subspecies:
- Western Slender Glass Lizards (O. attenuatus attenuatus) have shorter tails.
- Eastern Slender Glass Lizards (O. attenuatus longicaudus) have longer tails.
#12. Common Snapping Turtle
- Chelydra serpentina
- They weigh 10 to 35 lbs. and grow 8 to 18 1/2 inches long.
- The snapping turtle has a long tail, chunky head, and large webbed feet.
- The carapace (upper shell) coloring is black, brown, or olive with no distinct pattern.
These prehistoric-looking reptiles are widespread throughout Wisconsin.
Look for them living in marshes, lakes, ponds, rivers, and slow streams. They prefer areas with plenty of aquatic vegetation to hide in and insects, fish, frogs, and birds to eat.
Snapping Turtle Rangemap:
Credit: Virginia Herpetological Society
Snapping Turtles are best known for their powerful jaws. While there aren’t any recorded incidents of one of their bites causing amputation to a person, it can cause infections serious enough to require an amputation. In fact, their jaws are so strong that snapping turtles commonly eat other turtles!
These reptiles are usually docile but will become very aggressive if removed from the water. One of the best ways to calm an aggressive individual is to place it back into the water, where it can feel safe. I know I have personally picked them up with a large snow shovel to get them off the road and back to safety!
#13. Painted Turtle
- Chrysemys picta
- 2.5 to 10 inches long.
- The carapace is low to the ground and generally dark brown or black.
- As the name suggests, they have distinctive yellow, green, and red striping on the carapace, head, and limbs.
The Painted Turtle is one of the most recognizable reptiles in Wisconsin!
Look for its beautiful coloring of bright reds and yellow greens on its shell, limbs, and head. Painted Turtles live near calm, shallow water. They are attracted to areas with plenty of aquatic plants, their primary food source.
Painted Turtle Rangemap:
It’s almost impossible to accurately assess the population of Painted Turtles in Wisconsin. Many people keep them as pets and then release them into the wild, causing an ever-expanding range and unstable reproduction rates. These released reptiles can also put pressure on natural populations.
In the wild, Painted Turtles can hold their breath for up to 30 hours!
They also can remain dormant in near-freezing water for up to 4 months. This ability is essential when temperatures often go below freezing.
#14. Spiny Softshell Turtle
- Apalone spinifera
- Females are 7 to 21.25 inches long; males are 5 to 12.25 inches long.
- The carapace is flexible with a rough sandpaper texture, with a single row of spines or cones along the middle of the back. There is also a row of pointed tooth-like appendages on the edge of the carapace.
- Coloring is olive, gray, or brown, with black spots on some individuals.
Look for these reptiles in Wisconsin in lakes, rivers, and streams with sandy or muddy bottoms and little or no vegetation. I often see them sunning themselves on the banks while kayaking down slow-moving rivers.
Spiny Softshell Turtle Rangemap:
Spiny Softshell Turtles can “breathe” underwater by absorbing oxygen through the skin of their throats. This is a useful adaptation because they spend very little time out of the water, even sunning themselves in shallows or floating on the surface.
This reptile has some other unique adaptations that make it perfectly suited for its environment. Its leathery shell is extremely flat, and it has webbed feet and long claws, which allow it to swim quickly away from predators and bury itself in the muddy bottom.
Its most unique feature is its nose, which is long and snout-like! It can poke its nostrils out of the water and stay completely submerged to protect itself from hungry predators!
#15. Western Box Turtle
- Terrapene ornata
- 4 to 5.75 inches long.
- The carapace is high and rounded, resembling a helmet.
- Coloring is often dark brown or black background with radiating lines or dots.
Western Box Turtles live in open prairies and woodland areas. They prefer loose soil that is easy to burrow into and seek shelter under boards, porches, or other man-made objects.
Western Box Turtle Rangemap:
Western Box Turtles will eat almost anything they can fit in their mouths!
They have even been known to search through cow droppings for beetles!
Female Western Box Turtles have a unique ability when it comes to reproduction. They can mate once with a male turtle and keep the fertilized eggs safe in their bodies for over two years! Then, when the climate and season are most suitable, they lay the eggs.
What types of reptiles in Wisconsin have you seen?
Let us know in the comments!
And if you’re looking for a more comprehensive list of specific reptiles like snakes, lizards, or turtles, check out our ID guides to these fascinating creatures!
16 Common SNAKES That Live in Wisconsin! (ID Guide)
3 Common LIZARDS Found in Wisconsin! (With RANGE MAPS)