Wisconsin Native Snakes
Snakes play very important roles in many natural communities as predator and prey.
Snakes are extremely valuable to the agricultural community by keeping grain eating
mammals in check. Recent studies suggest that snakes are also valuable in reducing
disease threats posed by high rodent populations.
Many snake populations have declined in Wisconsin due to habitat loss and human persecution.
Even today, people who do not understand or appreciate their value continue to needlessly kill
them. Of Wisconsin's 21 species, 14 are considered rare and listed as endangered,
threatened or special concern.
Reptiles are a class of vertebrates made up mostly of snakes, turtles, lizards, and crocodilians.
These animals are most easily recognized by their dry, scaly skin. Almost all reptiles are cold-blooded
and most lay eggs, though some give birth to live young. Instead of possessing gills like fish or
amphibians, reptiles have lungs for breathing.
There are two species of rattlesnakes in Wisconsin, the Timber Rattlesnake and the Eastern Massasauga.
Both species are very rare.
But there are many non-venomous snake species that often mimic rattlesnakes. These mimics vibrate their
tails when they feel threatened. The sound of their tail “rattling” against vegetation, gravel or dry leaves
sounds almost identical to a rattlesnake.
Being cold-blooded (ectothermic) and thus unable to regulate their own body temperature
with metabolic activity, snakes are vulnerable to low temperatures. To deal with subfreezing weather, snakes
in Wisconsin hibernate during winter, although some scientists restrict that term to warm-blooded creatures
and instead refer to the overwintering dormancy of snakes as brumation.
After mating, the female snake stores the sperms in the oviduct for about 1 to 2 months.
The female then produces large eggs, which after releasing from the ovary are fertilized by the sperms
from the oviduct. It lays the fertilized eggs, about 10 to 15, in shallow holes or under the rocks. The
outer covering of snake’s egg is not hard, rather it resembles a soft leather.
The female snake guards and looks after the eggs till they hatch into young ones.
Some snake species warm the eggs by twitching their muscles, so as to speed up the hatching process.
The juvenile snake comes out of the egg, by biting the egg cover with the help of egg tooth. Until then,
it obtains nutrition from the egg yolk.
A young snake is known as a snakelet. A just hatched one can be called a hatchling.
Baby snakes feed on small reptiles and rodents. A young snake may shed its skin up to 4 times a year.
About 20% of the total snake species, especially those adapted to cold regions, give birth to live young
(viviparous). Some female snakes lay eggs even without fertilization, which is referred to as
parthenogenesis.
After the juvenile snakes emerge, they attain maturity, usually within 2 to 4 years. One of the major distinguishing
features between a young snake and an older snake is the frequency of molting per year. In case of a juvenile
snake, skin shedding takes place about 4 times a year, whereas an adult snake sheds only once a year, at the
most, 2 times per year. However, unlike insects in which molting allows the growth of the organism, renewal of
skin in snakes does not have a significant role in their growth.
All snakes are carnivorous (meat-eaters). Snakes eat rodents and other mammals, birds, reptiles,
fish, amphibians, insects and eggs. Some snakes, like rattlesnakes, are venomous and kill or paralyze
their prey by injecting poison through hollow fangs. The venom from venomous snakes paralyzes
the nervous system, causes heart and lung failure, or causes internal bleeding of their prey.
Catalog of Wisconsin Native Snakes
| Common Name |
Genus Species |
Status |
| Butler's Gartersnake |
Thamnophis butleri |
Special Concern |
| Common Gartersnake |
Thamnophis sirtalis |
Common |
| Common Watersnake |
Nerodia sipedon |
Common |
| DeKay's Brownsnake |
Storeria dekayi |
Common |
| Eastern Foxsnake (Pine) |
Pantherophis vulpinus |
Common |
| Eastern Hog-nosed Snake |
Heterodon platirhinos |
Common |
| Eastern Massasauga |
Sistrurus catenatus |
Endangered |
| Eastern Ribbonsnake |
Thamnophis sauritus |
Endangered |
| Gophersnake (Bullsnake) |
Pituophis catenifer |
Special Concern |
| Gray (Black) Ratsnake |
Pantherophis spiloides |
Special Concern |
| Lined Snake |
Tropidoclonion lineatum |
Special Concern |
| Milksnake |
Lampropeltis triangulum |
Common |
| North American (Blue) Racer |
Coluber constrictor |
Special Concern |
| Northern Ring-necked Snake |
Diadophis punctatus edwardsii |
Common |
| Plains Gartersnake |
Thamnophis radix |
Special Concern |
| Prairie Ring-necked Snake |
Diadophis punctatus arnyi |
Special Concern |
| Queensnake |
Regina septemvittata |
Endangered |
| Red-bellied Snake |
Storeria occipitomaculata |
Common |
| Smooth Greensnake |
Opheodrys vernalis |
Common |
| Timber Rattlesnake |
Crotalus horridus |
SpecialConcern |
| Western Ribbonsnake |
Thamnophis proximus |
Endangered |
| Western Wormsnake |
Carphophis vermis |
Special Concern |
Native Snakes Commonly Found In Wisconsin
Common Watersnake
This is a medium to large heavy-bodied snake, 24 to 40 inches in length. The background color
is gray, brown or tan and is marked with dark brown, red-brown or black transverse blotches,
which often fade with age. The underside is distinctive, white with bright red half-moons interspersed
irregularly with dark gray speckling.
Common watersnakes are usually found in or close to any
permanent waterbody but they prefer clean rivers.
DeKay's Brownsnake
This short thick-bodied snake, 8 to 15 inches in length, is gray or light brown in color, and is
marked with a light mid-dorsal stripe bordered by two rows of small dark spots. The underside
is white or light pink with dark pencil-point spots along the edges of the belly scales. Brownsnakes
live in the surface litter in many habitats, including oak savannas, prairies, southern lowland hardwoods,
marshes, old fields and under rubbish in vacant city lots.
Eastern Hog-nosed Snake
This medium-sized snake, 20 to 25 inches in length, also referred to as a "puff adder", has a sharply
upturned snout. The back has dark brown blotches on a brown-gold background color, and their underside
varies from mottled yellow to mottled gray or pink. Large, older adults are usually dark brown or gray and
may be patternless.
Most hognose snakes have a pair of dark black blotches on their neck that resemble "eyespots" when they
flatten their neck. Habitats include bracken grassland, oak savanna and sand prairies.
Milksnake
This snake which is 24 to 26 inches in length has a gray or light brown background color with three
rows of reddish-brown or brown blotches bordered with black. There is usually a whitish Y or V shaped
marking on the top of its head toward the neck. The underside is white with black rectangular markings.
Milksnakes live in oak savannas, northern and southern upland hardwoods, prairies and old woodlots
and pastures.
Northern Ring-necked Snake
A small, slender snake reaching a maximum total length 28 inches. Body uniformly bluish black to
slate gray or brownish, with a cream to yellow collar across neck. The snake's collar may be complete
or broken (or constricted) at middorsal line; venter cream to yellow and immaculate, or patterned with a single midventral row of small black spots to large half-moon-shaped spots; head black with white supralabials and a white chin.
Red-bellied Snake
Ring-necked snakes are small and thin, measuring from 9 to 15 inches in length. The body
is a dull blue-gray body, with a bright yellow belly that may have black spots. The black head is flattened,
and the scales are smooth and polished.
Ring-necked snakes are found in gardens, meadows, deciduous forests and rocky areas. Typical food
items of the ring-necked snake include small salamanders, snakes, and earthworms.
Smooth Greensnake
This species is often called the grass snake due to its color. The name "smooth" refers to the unkeeled
scales which give the snake a sleek, smooth texture and appearance. This beautiful little snake which is
14 to 24 inches in length is one of only five Wisconsin snakes to have unkeeled scales.
Smooth greensnakes frequent prairies, oak savannas, bracken grasslands, open areas in pine barrens
and grassy areas along forest edges. Greensnakes feed on insects, grubs and worms.
Eastern Foxsnake
The Eastern Foxsnake, which is 36 to 56 inches in length has many large reddish-brown, chocolate brown
or black mid-dorsal blotches along its back and other smaller blotches on its sides on a background color
of yellow, tan or olive gray. The head of adults is usually a dark copper, rust or orange color.
They live in a variety of open habitats including marshes, sedge meadows, prairies and old fields. Their diet
consists primarily of rodents and ground-nesting birds.
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Wisconsin Native Salamanders
Wisconsin Native Turtles
North American Native Turkey