Indiana is home to numerous fascinating animals but some of the most common ones are actually snakes. There are 32 species in the state, of which four are venomous. Snakes can be found in many habitats — there are shy and secretive snakes that hide away in forests, and there are even snakes that are frequently found in urban areas. However, there are also many which can be found in the water too. So, let’s learn about the water snakes in Indiana and find out which ones are dangerous!
1. Queen Snake (Regina septemvittata)
We’ll kick off the list with a particularly unique snake – the queen snake. Queen snakes are 15 to 24 inches long and have brown bodies with four dark stripes on their bellies. They also have dark stripes on their dorsal side, although these are usually only visible on juveniles. Queen snakes inhabit slow-moving, rocky-bottomed streams and prey predominantly on crayfish. Therefore, to protect them from the rocks as they are searching for food they have large, plate-like scales on the top of their head, as well as thicker scales underneath their chin. Their head is also distinctly flat to help them reach into narrow gaps between rocks. Queen snakes are fairly widespread across the central and northern regions of the state.
2. Cottonmouth (Agkistrodon piscivorus)
Cottonmouths are the only venomous water snake in Indiana. They are typically 24 to 36 inches long, although some may be longer, and they have brown bodies with dark brown to black crossband markings. Some snakes may have a dark brown ground color which renders the entire snake almost completely black. However, the most distinctive feature of them is their mouth which has a white lining. Cottonmouths can live in most freshwater areas, although they are extremely scarce in Indiana, with only a single population being known of in Dubois County. Cottonmouths possess cytotoxic venom which can cause tissue death, although it is rarely fatal.
3. Northern Water Snake (Nerodia sipedon)
The first true water snake in the state is the northern water snake which is widespread across the state and lives in most freshwater habitats. They are approximately five feet long and have a reddish to dark brown ground color which is overlaid with darker blotches and crossbands. They have a very similar appearance to the cottonmouth, and as such they are often mistaken for them. Northern water snakes are powerful animals and prey on a wide range of fish and amphibians. They can be highly defensive when they are disturbed and may strike to protect themselves. Although they are not venomous, they do have a substance in their saliva which prevents blood from clotting properly, so if you are bitten you should always seek medical attention.
4. Plain-Bellied Water Snake (Nerodia erythrogaster)
The plain-bellied water snake is the next true water snake in Indiana. These snakes mainly inhabit the south and southwestern region of Indiana and are a state-endangered species. They prefer to live in shallow but open wetland areas, such as swamps and floodplains. Plain-bellied water snakes are 24 to 40 inches long and are brown or olive-green on their dorsal side. They also have a plain, yellowish-colored belly. Plain-bellied water snakes are active both during the day and night and prey on fish, frogs, salamanders, and crayfish.
5. Diamond-Backed Water Snake (Nerodia rhombifer)
Diamond-backed water snakes are large, powerful snakes and range between 30 and 48 inches long. They have brown to dark brown bodies with distinctive black diamond-shaped markings. Dimaond-backed water snakes typically prefer slow-moving water, such as swamps, streams, and ponds. They can often be spotted basking on rocks at the shore or hanging from nearby vegetation. However, at the first sign of danger, they will typically head straight back to the water. Diamond-backed water snakes are not venomous and swallow their prey alive. Their diet consists of fish, crayfish, frogs, toads, and salamanders.
6. Butler’s Garter Snake (Thamnophis butleri)
The next water snake in Indiana is Butler’s garter snake. Butler’s garter snakes are a state-endangered species and live in a few locations in the far northwestern corner. They prefer open habitats, such as wet meadows and the edges of lakes, streams, and swamps. Butler’s garter snakes are small snakes and only reach 15 to 20 inches long. They have an olive brown to black ground color which is overlaid with three yellow or white stripes. Their lateral stripes are located on the third row of scales, the upper part of the second row, and the lower part of the fourth row. They mainly prey on earthworms but will also sometimes prey on salamanders and frogs.
7. Plains Garter Snake (Thamnophis radix)
Another garter snake in the state is the plains garter snake. Plains garter snakes reach approximately 36 inches long and are greenish to dark brown. They have three yellow or orange stripes, with the two side stripes being located on scale rows three and four. Plains garter snakes only inhabit the northwestern region of Indiana. They typically live close to slow-moving bodies of water, such as streams, ponds, and marshes. When disturbed, they will typically flee into the water. However, plains garter snakes may sometimes be defensive if they are threatened and may bite to defend themselves, although they are not considered to be dangerous.
8. Common Garter Snake (Thamnophis sirtalis)
The next water snake in Indiana is the common garter snake. Common garter snakes are typically 20 to 30 inches long. They have dark brown to black bodies with three stripes which are typically yellow, orange, or white. They have one stripe down the center of their back and a lateral stripe down each side which is located on scale rows two and three. Common garter snakes also typically have a series of black or red spots on their sides between their stripes. Common garter snakes occur statewide and usually live close to a permanent source of water. They mainly prey on fish and frogs which they immobilize using a venom-like substance. Despite this, there are completely harmless to humans.
9. Eastern Ribbon Snake (Thamnophis saurita)
The eastern ribbon snake has a similar appearance to the garter snakes in the state, with a dark ground color and three brightly-colored yellow stripes. However, eastern ribbon snakes typically have a much thinner body and a longer tail which can be as much as one-third of their total body length. In total, they are approximately 20 to 32 inches long. Eastern ribbon snakes live in scattered locations across the state. They typically prefer to live near the edges of lakes, ponds, streams, and swamps where there is plenty of low vegetation for cover. They are quick to flee back into the water at the first sign of danger but tend to remain at the surface instead of submerging themselves.
10. Western Ribbon Snake (Thamnophis proximus)
The final snake and the second ribbon snake in the state is the western ribbon snake. Western ribbon snakes are approximately three feet long and have dark brown or black bodies with bright orange dorsal stripes. Their lateral stripes may be light orange, yellow, or cream. They also have a white spot on their head which can be used to distinguish them from the eastern ribbon snake. Western ribbon snakes are a species of special concern within Indiana and mainly live in the northwestern corner of the state. They live close to water and prey on a variety of amphibians and small fish.
Summary of the 10 Water Snakes Lurking in Indiana Waters
|#||Water Snake||Length||Danger Level|
|1||Queen Snake||15 – 24 inches||Low – avoids conflict|
|2||Cottonmouth||24 – 36 inches||High – venom can cause tissue damage and death|
|3||Northern Water Snake||24 – 42 inches||Moderate – bites are usually not fatal but require immediate medical attention|
|4||Plain-Bellied Water Snake||24 – 40 inches||Low – avoids conflict|
|5||Diamond-Backed Water Snake||30 – 48 inches||Low – avoids conflict|
|6||Butler’s Garter Snake||15 – 20 inches||Low – avoids conflict|
|7||Plains Garter Snake||Up to 36 inches||Low – will bite in self-defense|
|8||Common Garter Snake||20 – 30 inches||Low – avoids conflict|
|9||Eastern Ribbon Snake||20 – 32 inches||Low – avoids conflict|
|10||Western Ribbon Snake||Up to 36 inches||Low – avoids conflict|
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