Illinois is home to a wide variety of frog species and people commonly find frogs around their homes because of it. Because of the number of frog species that can be found in Illinois, some people may confuse their names and characteristics.
There are about 23 species of frogs you can find in Illinois. Across the State, you can find frogs like the American Bullfrog, Bird-Voiced Tree Frog, Blanchard’s Cricket Frog, Crawfish Frog, Gray Tree Frog, and Green Tree Frog.
Here is a table of 10 frogs you can find in Illinois:
|Frog Species||Illinois Location||Habitat|
|Blanchard’s Cricket Frog||Statewide||Aquatic|
|Gray Tree Frog||Statewide||Arboreal|
|Bird Voiced Tree Frog||South||Arboreal|
|Green Tree Frog||South||Aquatic|
|Illinois Chorus Frog||Central, South-Central||Terrestrial|
|Pickerel Frog||North, East, South-West||Aquatic|
|Plains Leopard Frog||West, Central, South||Aquatic|
Some of these frogs are native to Illinois. However, a few of the 23 species were introduced and became invasive. That said, I have seen a lot of these frogs and know how to differentiate them and would like to help you do the same!
It is a lot of fun to go looking for them in the wild and to observe them in their natural habitat. So let’s dive into the frogs you can find in Illinois and my top tips on spotting them.
1. American Bullfrog
American Bullfrogs are native to Illinois and you can find them in every part of the state. They, usually green or gray-brown with a yellow belly for males, and a few brown spots. American Bullfrogs are the biggest frog in North America, generally weighing about 1.5 pounds and growing up to 8 inches from snout to vent as adults.
You can find an American Bullfrog in stagnant water surrounded by vegetation. They make an intense and loud below-sound during mating season. If you hear these frogs at night, or any others for that matter, find out how to get a good night’s sleep despite their loud croaking on our blog.
The American Bullfrog, usually green or gray-brown, with few brown spots, is the biggest frog in North America. This frog weighs about 1.5 pounds and usually grows up to 8 inches.
You can find an American Bullfrog in stagnant water surrounded by vegetation. Furthermore, the sound an American Bullfrog makes is intense and loud. The male and female American Bullfrogs make this sound (called a call).
2. Blanchard’s Cricket Frog
Blanchard’s Cricket Frog is a little tree frog that has a variable skin color depending on its environment. It can switch between brown, green, gray, and reddish-brown thanks to camouflage. This change is based on specific environmental conditions and the presence of predators.
Blanchard’s Cricket Frogs are found all over the state of Illinois. Being aquatic, generally, they live near ponds, lakes, and streams. Like most aquatic frogs, they choose to breed in calm freshwater.
Blanchard’s Cricket Frogs cannot withstand the cold and are not tolerant of freezing. They hibernate like most aquatic frogs at the bottom of ponds, below the ice, but only live for about a year.
3. Gray Tree Frog
The Gray Tree Frog ranges in color from green, brown, or gray depending on their surroundings. During the daytime, the frog usually sleeps on tree branches or leaves. Their toes have sticky pads that help them climb trees and stick to branches.
Since they climb so well and are active at night, they are often found on people’s windows or sliding doors. Gray Tree Frogs are found all over Illinois and make a very short call during mating season which is generally from April to June (CTNF).
4. Wood Frog
Wood Frogs are typically rust-colored, brown, or tan and are generally easy to recognise thanks to their dark eye masks. They are fairly tiny, only growing to approximately 2 – 2.8 inches as adults, and primarily live in forests, freshwater wetlands, and woodland vernal pools. They are easy to hear as well, as their distinct mating calls sound like a quacking duck.
Wood Frogs are fairly tolerant of colder habitat conditions and even extreme colds in some cases. Wood Frogs will freeze approximately 65% of its body to hibernate during Winter. Their heart stops beating, their blood freezes, and their breathing and muscle movements temporarily cease. Once the early spring arrives, Wood Frogs begin returning to life as they thaw and start calling to mate.
5. Bird-voiced Tree Frog
The Bird-Voiced Tree Frog derived its name from the sound it produces which sounds like a bird chirping. Bird-Voiced Tree Frogs are primarily found in the southern tip of Illinois, hanging on tree branches above small bodies of freshwater.
Bird-Voiced Tree Frogs vary in color yet they are generally grey or green. A distinctive feature of this tree-dwelling frog is the yellow area between the creases of its legs.
6. Crawfish Frog
The Crawfish Frog got its name from its most popular diet, crawfish. Other than crawfish, the Crawfish Frog also eats beetles, smaller amphibians, and reptiles. The frog has a large and thick body with many spots, but a clean white abdomen.
The Crawfish Frog can be found in lowlands, meadows, brush fields, and crawfish holes. In the state of Illinois, you can find them in the southern region. The call of a Crawfish Frog is profound and loud.
7. Green Tree Frog
The Green Tree Frog is not always green although its name may give that impression. Green Tree Frogs range from light green to dark green with a white line along its sides. This frog can grow to 2.5 inches remaining fairly small to be able to stick to leaves and branches.
You can find them naturally in the southern part of Illinois, in marshes, swamps, little ponds, and streams.
8. Illinois Chorus Frog
Illinois Chorus Frog is a tan gray-colored frog with many dark brown or gray irregular spots and marks. It has a V-shaped mark in-between the eyes, a dark dot below each of its eyes, and a dark line from the nose to the shoulder.
This tree frog has a few similarities with toads since they enjoy burrowing underground in sandy soil. Therefore, the Illinois Chorus Frog spends most of its time underground and is hard to spot. The frog is found in the central and south-central parts of Illinois.
9. Pickerel Frog
Pickerel Frogs are distinguished by two parallel lines of square-shaped spots which run down their backs. This frog species is in the greatest need of conservation in Illinois, as they struggle with complex habitat requirements.
These frogs move habitats depending on the climate changes. They enjoy cold, oxegen-filled streams in Winter, after which they move to warmer water to reproduce in the Spring. Adult Pickerel Frogs then seek out forests, where they can scavenge for food during the Summer.
The Pickerel Frog is found in the North, East, and Southwest parts of Illinois, generally near the borders.
10. Plains Leopard Frog
The Plains Leopard Frog is brown and has extensive and rounded dark dots with light outlines. The Plains Leopard Frog is well known for its broken and irregular skin ridges running down the back.
These amphibians can be found close to streams, ponds, creeks, and even ditches. However, in wet or moist weather, they usually migrate away from the water. The Plains Leopard Frog is spread all over the central and southern regions of Illinois
More About Frogs in Illinois
I love to go out looking for frogs and if you are in Illinois, by all means, make frog searching a part of your trip! Illinois is a great place to capture photos of a diverse variety of frogs.
Learn more about where to find frogs in the USA in our guides below:
- 12 Types of Frogs You Can Find in Michigan
- 11 Types of Frogs You Can Find in Wisconsin
- 8 Types of Frogs You Can Find in Maine
- 13 Frogs You Can Find In New Jersey
- Where Can You Find Toads in the USA?
- Where Can You Find Frogs in the USA?
- 10 Tips to Find Aquatic Frogs
- 8 Tips to Find Tree Frogs
- 4 Easy Ways to Find Toads