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Are There Water Snakes in Wisconsin?

Wisconsin has plenty of wildlife that’s as diverse as its landscape. Wisconsin’s habitats include boreal forests, lakes, swamps, marshes, and more. With so many different ecosystems to explore, it’s no surprise that Wisconsin is home to nearly 700 different species of animals, including quite a few different types of snakes. Since this state is one of those bordering the Great Lakes, you may be wondering about the water snakes in Wisconsin.

In the following article we inform you about true water snakes that can be found in Wisconsin.

Water snakes in Wisconsin

In Wisconsin, there’s only one species of water snake from the genus Nerodia, and that’s the common water snake. It’s also one of the most widespread snakes in the state, where they’re abundant in habitats near bodies of water.

Common water snake

Common watersnake
Common watersnake | image by USFWS Pacific Southwest Region via Flickr | CC BY 2.0
  • Scientific Name: Nerodia sipedon
  • Length: 24 to 40 inches
  • Venomous: No

The only true water snake found in Wisconsin is the common water snake. This species is prevalent in the Great Lakes region and prefers to live in clean water with abundant food sources, such as rivers, streams, lakes, and ponds. Common water snakes are among the most common snakes in the state, especially among residents who live near their natural habitats.

These animals can grow to be up to 40 inches long, with some reaching 53 inches. They’re also non-venomous, but are frequently confused with the venomous cottonmouth snake. Cottonmouths aren’t native to Wisconsin, so you shouldn’t be concerned if you live there. Additionally, this true water snake doesn’t bite humans unless it feels threatened.

Some semi-aquatic snakes in Wisconsin

If you live in Wisconsin and have noticed snakes swimming in or near the water, these could be the snakes you discovered. However, keep in mind that these snakes aren’t true water snakes and don’t belong to the genus Nerodia.

1. Common Garter snake

Common garter snake
Common gartersnake | image by Greg Schechter via Wikimedia Commons | CC BY 2.0
  • Scientific Name: Thamnophis sirtalis
  • Length: 17-26 inches
  • Venomous: No

The Common Gartersnake is a long, thin, brown snake found in Wisconsin. They’re the most abundant snake species in Wisconsin and prefer to live near water sources, where they’ll frequently swim to escape danger. Their primary habitats, however, are forest edges, swamps, overgrown lawns, and grassy areas.

This non-venomous garter snake feeds primarily on amphibians, worms, insects, and small fish. These snakes are typically 17 to 26 inches long, with a dark brown body with light stripes.

2. Eastern Massasauga

Eastern massasauga
Eastern massasauga | image by Peter Paplanus via Flickr | CC BY 2.0
  • Scientific Name: Sistrurus catenatus catenatus
  • Length: 20-32 inches
  • Venomous: Yes

In Wisconsin, the Eastern Massasauga is a rare and endangered snake species. Furthermore, it’s one of the two venomous snakes that can be found in the state. This species can be found from the south-central to west-central parts of the state, particularly in floodplain habitats where this rattlesnake species is most common.

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They can swim and feed on semi-aquatic animals like frogs, fish, and crayfish, but they’re unlikely to be found in open water. Eastern Massasauga is most likely to be seen in early April when it emerges from overwintering and remains active until mid-November, just before winter arrives.

3. Eastern Ribbon snake

Eastern ribbon snake
Eastern ribbonsnake | image by John J. Mosesso via Wikimedia Commons
  • Scientific Name: Thamnophis sauritus
  • Length: 18 to 34 inches
  • Venomous: No

The Eastern Ribbon snake is a nonpoisonous snake that lives in bog relics near or south of the Tension Zone. They’re also among the snakes you’ll most likely encounter in the water because they’re semi-aquatic and good swimmers. This snake isn’t aggressive, but it’ll bite if cornered or picked up without care.

The Eastern Ribbon Snake is commonly confused with garter snakes due to its dark brown or black coloration with three yellow stripes.

4. Queensnake

Queensnake | image by Peter Paplanus via Flickr | CC BY 2.0
  • Scientific Name: Regina septemvittata
  • Length: 15 to 25 inches
  • Venomous: No

The queen snake is a small, aquatic snake found in Wisconsin. Despite the fact that they’re endangered in the state, they can still be found in areas near water sources. They primarily consume crayfish and other aquatic animals, such as fish, but will also consume tadpoles.

Queen snakes are solitary outside of their breeding season, which means they can be seen living alone with no companions. They’re active from April to October and spend the winter in crayfish band artificial structures. These snakes are distinguished by their light brown to grayish bodies with yellow stripes on the sides.


Do water snakes in Wisconsin bite?

The common water snake found in Wisconsin is a non-venomous snake that lives in freshwater or wetlands. It’ll bite you if it perceives that you or your environment pose a threat, but its bites aren’t venomous and won’t harm you unless you have an allergy to them. However, it’s still important to exercise caution around water snakes because their bites can still be painful.

Are water snakes common in Wisconsin?

Water snakes are common in Wisconsin because they can live in various water environments. With its 15,000 lakes and over 12,600 rivers and streams, it’s natural that water snakes would be plentiful.

They also live in slow-moving streams, as well as near ponds and marshes. These habitats also provide a variety of food sources for these snakes, which helps in their survival.