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 vocalizations of Rana pretiosa can be described as a quiet series of rapid lo-pitched clicks or knocks. They are typically produced during the day while the frog is floating on the surface. Frogs may also call underwater.
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The following sounds were recorded on a sunny afternoon in late February in Thurston County Washington at the study site of Kelly McAllister with the Washington Department of Fish and Wildlife (shown below right.) This is one of the last remaining populations of this frog in Washington state. The air temperature was around 45 degrees with occasional wind gusts. The habitat (shown on the bottom left) was a flooded field next to a slowly-moving drainge. The frogs called while floating in shallow water (middle left) with only the top of their head visible above water. Background sounds consist of birds, including crows and red-winged blackbirds, wind in dry grass, and distant traffic.
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This is a 5 second recording of two advertisement calls.
This is a 28 second continuous recording of the advertisement calls of a small group of male frogs, recorded from a short distance.
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This is a 21 second continuous recording of the advertisement calls of a small group of male frogs from a short distance.
This is a 9 second recording of one frog calling two times from underwater at the end of the day in Klickitat County. Distant Pacific Treefrogs are heard in the background. Courtesy of Marc Hayes and Chris Rombeaugh. |
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Waveform and Sonogram |
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This is a recording of the advertisement calls of an Oregon Spotted Frog recorded during the day in Thurston County, Washington.
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!" |
The following release calls were recorded in Klickitat County, Washington, courtesy of Marc Hayes, who maintains several study sites for this frog at a National Wildlife Refuge. Marc gently grasped a frog across the back, and it produced the release call until it was released.
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This is a 4 second recording of the release calls of an adult male frog.
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This is a 5 second recording of the weaker release calls of a sub-adult frog.
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You can listen to more recordings of Oregon Spotted 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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