There are 21 different types of toad and frog sounds in Illinois. These include eight true frog calls, nine tree frog sounds, two true toad trills, one spadefoot toad call, and one narrow-mouthed toad noise.
Frog calls in Illinois are most prevalent during the breeding season, which starts in early spring. Males gather in ponds and wetlands to call, often creating loud choruses, with the intent of attracting a female to mate. Females use these calls to discern the attractiveness of a potential suitor (longer and louder calls are preferred among females in many species).
Spring Peepers and Wood Frogs kick things off as the snow melts, and are soon joined by Leopard Frogs and American Toads. Later in the spring, gray tree frogs, Fowler’s toads, cricket frogs, and green frogs will take over as the most common croakers.
An American Toad (Anaxyrus americanus), which makes a high-pitched musical trill. Source: iNaturalist.
For all the species below, I have included only the males’ mating (or advertisement) calls, as these are by far the most often heard. While frogs make other noises, including alarm, release, and territorial calls, these are often short, tough to identify to species, and not as frequently recorded.
There are eight species of tree frogs in Illinois. These creatures share several physical characteristics, including small, narrow bodies and enlarged toe pads that help them climb trees or bushes. However, there are several types of tree frogs, including chorus frogs and cricket frogs, and their sounds can vary quite a bit, as you’ll see below.
Blanchard’s Cricket Frog
Acris blanchardi
Blanchard’s Cricket Frog makes a set of repeated and rapid clicks, which resemble the sound of two small rocks being tapped together.
Cope’s Gray Treefrog
Hyla chrysoscelis
The mating call is a trill that sounds harsher than the call of the Gray Treefrog. The pulse rate is faster compared to the Gray Treefrog when both are calling in the same area at the same time.
American Green Treefrog
Hyla cinerea
The mating call is a short, nasal “honk!” made once or twice per second. This recording of Green Treefrog sounds from the National Park Service shows a faster call compared to the video.
Eastern Gray Treefrog
Hyla versicolor
The advertisement call of the gray treefrog is a musical trill that lasts about half a second and is repeated every few seconds. While it is similar to the Cope’s Gray Treefrog call, the pulse rate (speed of the call notes) is significantly slower if both frogs are calling in the same temperature.
Spring Peeper
Pseudacris crucifer
One of the most well known sounds in the Eastern United States, the spring peeper’s mating call is a loud, ongoing “peep” that repeats once a second or slightly faster.
Upland Chorus Frog
Pseudacris feriarum
The frog makes a clicking trill that rises at the end. This noise can be tough to tell apart from Boreal, New Jersey, and Midland Chorus Frogs, which sound very similar.
Boreal Chorus Frog
Pseudacris maculata
The advertisement call is a metallic-sounding trill that lasts a little more than a second and rises in pitch at the end. Calls are typically a couple seconds apart. This frog sounds similar to Midland and Upland Chorus Frogs.
Strecker’s Chrorus Frog
Pseudacris streckeri
The advertisement call is a metallic-sounding “peep”, very similar to the Ornate Chorus Frog. The call is slightly lower in pitch, but can be difficult to differentiate in areas where the species overlap.
Midland Chorus Frog
Pseudacris triseriata
The Midland Chorus Frog mating call is a rapid clicking trill that lasts less than a second and rises slightly in pitch at the end. It sounds a little like running your finger along the teeth of a comb.
True Frog Sounds and Calls in Illinois
Eight amphibians in Illinois are considered “true frogs”, meaning they are members of the Ranidae family. These are the typically medium to large-sized “classic” frogs, the ones that most fit the image that pops up in your mind when someone says “frog”.
In Illinois, true frog soundscome from the Crawfish Frog, Plains Leopard Frog, American Bullfrog, Green Frog, Pickerel Frog, Northern Leopard Frog, Southern Leopard Frog, and Wood Frog.
These frogs feature a range of physical and vocal differences. Read on to learn about the differences among these true frog sounds and calls.
Crawfish Frog
Lithobates areolatus
The mating call of the Crawfish Frog is a one-second-long, low-pitched, nasal snore.
Plains Leopard Frog
Lithobates blairi
The mating call of the Plains Leopard Frog is made up of between two and four chucking notes, repeated quickly several times. Each set of chucks rises slightly in pitch, and may end with a grunt.
Bullfrog
Lithobates catesbeianus
The bullfrog mating call is a loud, low-pitched “ruuum, ruuum, ruuuum.” They also have a high-pitched alarm call when they suddenly jump into the water if startled.
Green Frog
Lithobates clamitans
The Green Frog makes a sudden, loud “gunk!”. Many liken it to someone plucking a loose banjo string. They usually call in a few times in a row, with volume and pitch decreasing each time.
Pickerel Frog
Lithobates palustris
Pickerel Frogs make a soft snore that lasts about two seconds, sometimes with a few garbled notes or “gunk!” that sounds similar to the Green Frog. The snore of the Pickerel Frog is much shorter than that of the Northern Leopard Frog.
Northern Leopard Frog
Lithobates pipiens
The Northern Leopard Frog’s mating call is a long snore that lasts at least three seconds, and is often followed with grunts or chuckles. The call usually increases in volume until trailing off at the end.
Southern Leopard Frog
Lithobates sphenocephalus
The Southern Leopard Frog quickly repeats a set of five to ten “chucking” notes, often followed by grunts. These chucks get faster in warmer temperatures.
Wood Frog
Lithobates sylvaticus
The Wood Frog’s call is a series of explosive clucks; some have compared this to the sound of hoarse duck quacks.
Toad Calls in Illinois
There are two true toads (members of the Bufonidae family) in Illinois: the American Toad and Fowler’s Toad. There is also a spadefoot (Scaphiopodidae family) toad, which has a protrusion on its foot to help it dig, which true toads do not have.
Finally, there is the Eastern Narrow-mouthed Toad, which is actually in the narrow-mouthed frog (Microhylidae) family, and so not a complete fit with other toads. However, their call is similar enough to other toads that I have included them here.
American Toad Calls
Anaxyrus americanus
The mating call is a musical trill that typically lasts between five and thirty seconds. During the breeding season, males’ make sounds that often alternate or overlap, and have slightly different pitches.
Fowler’s Toad Sounds
Anaxyrus fowleri
Fowler’s Toads make a buzzy trill that lasts between one and five seconds. Some people liken the sound to that of a crying baby or a woman screaming. Fowler’s Toads sometimes hybridize with American Toads, and calls end up sounding like a mix of the two species.
Eastern Spadefoot Calls
Scaphiopus holbrookii
The mating call of the Eastern Spadefoot is an explosive noise that sounds a bit like a person gagging. It’s not the most pleasant sound. The noise is repeated every five to ten seconds.
Eastern Narrow-mouthed Toad
Gastrophryne carolinensis
The Eastern Narrowmouth Toads makes a loud, sometimes startling high-pitched “weeeeee!” It can sound similar to the bleat of a baby animal.
References and Further Reading
Some of the best quality information online about individual frogs can be found at AmphibiaWeb and Animal Diversity Web. These provide some details on calls, among a host of other valuable content.
A whole variety of YouTube channels provide great examples of sounds and calls, several of which are included here. These creators range from passionate individuals to state agencies. If you liked a video embedded here, check out more from these channels.
