There are 17 types of toad and frog sounds in Delaware. This includes seven true frog sounds, seven tree frog calls, two true toad calls, and one spadefoot call. These species create a rich symphony on many spring and summer nights.
An American bullfrog, a common source of frog calls in Delaware.
For all these frogs, I have included only the males’ mating (also known as advertisement) calls, as these are by far the most often heard. While other frogs make other noises, including alarm, release, and territorial calls, these are often short, tough to identify to species, and not often recorded.
There are seven species of tree frogs in Delaware: Northern Cricket Frog, Spring Peeper, Eastern Gray Treefrog, Cope’s Gray Treefrog, Barking Treefrog, Green Treefrog, and Upland Chorus Frog. These are all members of the Hylidae family and share several physical characteristics, including small, narrow bodies and enlarged toe pads to help climb trees or bushes. However, Delaware tree frog sounds are clearly different across species, as you’ll see below.
Northern Cricket Frog
Acris crepitans
The advertisement call is a series of clicks than have been described as “two stones being tapped together”. The clicks start slow, then happen two or three at a time, building into a frenzy before slowing again.
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.
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.
Barking Treefrog
Hyla gratiosa
The call of the Barking Treefrog actually does resemble the sound of a barking dog! Mating calls are short “aarf” type sounds made every second or so.
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.
Delaware True Frog Sounds and Calls
Six amphibians in Delaware 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 Delaware true frog sounds come from the Bullfrog, Green Frog, Pickerel Frog, Atlantic Coast and Southern Leopard Frogs, Carpenter Frog, and the Wood Frog.
Closer examination can reveal a range of physical and vocal differences, however. Read on to learn about the differences among Delaware’s true frog sounds and calls.
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.
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.
Carpenter Frog
Lithobates virgatipes
The mating call is a set of sharp, paired notes, repeated frequently. It sounds like people hammering nails at a construction site.
Toad Calls in Delaware
There are two true toads (members of the Bufonidae family) in Delaware, one spadefoot toad (in the Scaphiopodidae family), and the Narrow-mouthed Toad (in the Microhylidae family). They make trills that vary in their length and musicality. You’ll likely find some of these sounds pleasing and relaxing, while others may feel harsh and unpleasant. Check out Delaware’s toad calls below.
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
This sound guide draws from a number of sources, including several of the following:
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.
Several books provide detailed and well-researched accounts of these frogs, including The Frogs and Toads of North America (2009) by Elliott, Gerhardt, and Davidson and Frogs and Toads of the United States and Canada (2013), by C. Kenneth Dodd.
