A Guide to California's
Reptiles and Amphibians
Sounds of
California Red-legged Frog - Rana Draytonii
Baird and Girard, 1852
Adult male, Fresno County|
Male frogs and toads sometimes make a variety of sounds. These calls can have different functions. Advertisement Calls The advertisement call is the most well-known call of a frog or toad. It is made by a male during the breeding season to establish his territory and repel rival males and to attract females as potential mates. Males usually make the call in or near bodies of water near areas that are attractive to a female as a good place to lay her eggs. Advertisement calls can be heard during the evening and at night, and often during daylight at the peak of the breeding season. Sometimes an advertisement call will be heard outside of the breeding season and away from water. The reason for this is not understood. Each species has its own unique advertisement call. This is necessary to differentiate them when there is more than one species calling. The evolution of this specific male advertisement call and its recognition by females is considered to be an important isolating mechanism in the evolution of a species. The advertisement call of the California Red-legged Frog can be described as a weak series of 5 - 7 notes, sounding like uh-uh-uh-uh-uh, lasting 1 - 3 seconds that do not have a lot of volume. After the series there is sometimes a last note which is similar to a growl or groan.The calls are made during the day and at night in the air and underwater. |
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The following sounds were all recorded on a sunny morning in early March at the edge of a pond in Monterey County. The pond at the time of the recordings is shown below. Air temperature was around 48 degrees with a light wind. Birds, wind noise, and water flowing into the pond from a small seep can be heard in the background. Thanks to Susan Whitford and David Keegan and the Santa Lucia Conservancy for their generous assistance in helping me make these recordings. |
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 This is a 5 second recording of a series of two advertisement calls of a single male frog. |
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| This is a 2 second recording of one advertisement call of a single frog, which includes the growl at the end that is characteristic of this species. (Compare to Rana aurora.) |
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| This is a 29 second recording of the calls of two or three frogs, including some ending growls. |
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| This is a 27 second recording of the calls of one frog who is joined at the end by another. |
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| This is a 29 second recording of the calls of two or three frogs, including some ending growls. A loud Red-winged Blackbird sings in the background. |
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| This is a 30 second recording of the calls of two or three frogs, including some ending growls. |
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The following sounds were all recorded on a sunny afternoon in early March at the edge of a pond in Contra Costa County. The pond at the time of the recordings is shown below right. Air temperature was around 60 degrees with a moderate wind. |
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| This is a 22 second recording of the calls of two frogs, including an ending growl. Red-tailed hawks can be heard calling in the background along with other distant singing birds, insects, and wind noise. This is a 4 second recording of one call and an ending growl. |
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The following sounds were recorded at night in early February at the edge of a coastal marsh in Marin County. The location as it appeared the following morning is shown below right. Air temperature was 47 degrees. Sierra Treefrogs can be heard in the background. |
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| This is a 1 minute and 31 second continuous recording of the sounds of several California Red-legged Frogs, with one frog in the foreground, another slightly farther, and a few in the distance. |
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| Short Video | |
| This video shows breeding habitat on a sunny day in late January with several male frogs calling along with some birds singing. You'll probably have to turn the volume all the way up to hear the frogs, but you won't see them. I've tried to photograph frogs calling here but without any luck. It appears that at this location they call from locations hidden within the reeds, or maybe even under the water. |
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| Waveform and Sonogram | |
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| This is a recording of the advertisement calls of a California Red-legged Frog recorded during the day in Contra Costa County. The image above is a visual representation of this call. Click on it to see a larger image. Click here for information about how to read the waveform and sonogram images. |
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Release Calls A release call is produced by a male frog or an unreceptive female frog when a male frog or other animal gets on its back and grabs its sides in the position used for mating or amplexus. It's a frog's way of saying "Get off my back! Let go!" |
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| This is an 11 second recording of two frogs giving their release calls on a pond in Contra Costa County when they were in amplexus with California Toads (sex uncertain.) Other male toads were trying to wrestle them away from the other toads. The picture on the right shows the scene, and you can also see them in the video directly below. California Toads, red-winged blackbirds, and a Sierran Treefrog are also heard in the background. |
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| Short Video | |
| Two male California Red-legged Frogs are seen here in a Contra Costa County pond in March in amplexus with California Toads (possibly female.) Male toads attempt to wrestle the frogs off their prospective mates. When they grab the frogs, the frogs give their low chuckling release call, while the toads make their peeping release call. The video also starts and ends with the frog release calls. |
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You can listen to more recordings of California Red-legged Frogs on this cd: Carlos Davidson - Frog and Toad Calls of the Pacific Coast  and on the cd that comes with this book: Lang Elliott, Carl Gerhardt, and Carlos Davidson - The Frogs and Toads of North America - Houghton Mifflin Harcourt.  |
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