A Guide to California's
Reptiles and Amphibians
Sounds of
American Bullfrog - Lithobates catesbeianus
Shaw, 1802(= Rana catesbeiana)
Adult Male Calling |
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 American Bullfrog can be described as a very loud low-pitched two-part drone or bellow. This is one of the loudest frog calls heard in California. The calls are made during the day and at night. An older female American Bullfrog will also vocalize sometimes along with males, which creates more competition among the males, allowing the female to further choose the most dominant male. |
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| Two males calling in daytime in Santa Clara County with small waves made by the vibrations of their throat sacs visible on the survace of the water. © Yuval Helfman |
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 This is a 3 second recording of two advertisement calls of one male made at night on the Colorado River in Imperial County (shown to the right.) |
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| This is a 9 second recording of a short series advertisement calls of one male made at night on the Colorado River in Imperial County (shown to the right.) |
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| This is a 14 second recording of a short series advertisement calls of two males made at night on the Colorado River in Imperial County (shown to the right.) |
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| This is a 22 second edited recording of the advertisement calls of three males made at night at an irrigation canal in Imperial County (shown to the right.) |
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| Short Videos of American Bullfrog Advertisement Sounds | |
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large male American Bullfrog makes advertisement calls at night from a lake in Arizona. |
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| A big male American Bullfrog calls from the edge of a lake in the daytime. He sat making single calls every few minutes, until suddenly lots of other bullfrogs began calling all around him and then he made his full calls. Here we see him start with a full series of calls, then wait a bit before making a second series of calls, but this time starting with some longer notes before doing his typical calls. There was a second male about 10 feet from him who was silent, but after the first male makes his second full series of calls, the second male begins calling at 1 minute 10 seconds into the video. We can't see him, but his calls sound about as loud as the first frog, but you hear them when you can see that the first frog is silent. This calling disturbed the first frog so much, he made a short, sharp, territorial call and leaps in the air in the direction of the second frog. When I finally found him again, he was closer to the second frog, but the second frog hadn't moved. |
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| Waveform and Sonogram of Advertisement Call | |
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| This is a recording of the advertisement calls of an American Bullfrog recorded during the day in Imperial 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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Alarm Calls American Bullfrogs, primarily juveniles, produce an alarm call, a fast squeak, which is usually made before a frog jumps into the water to escape from danger. |
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| This is an edit of three sequences of alarm calls recorded at the edge of a pond in Grant County, Washington (shown to the right.) The first is a single call and splash; the second is two calls and splashes; and the third is one call followed by the sound of the frog jumping over a mat of dry reeds. |
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| This is a 1 second recording of the alarm call of a juvenile American Bullfrog jumping into an irrigation canal in Sacramento County during daylight (shown to the right.) |
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| This is a 2 second recording of the alarm call of an adult American Bullfrog jumping from the shore into a small creek in Stanislaus County during daylight (shown to the right.) (Background sounds include rustling clothing and a flying insect.) |
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| This is a 1 second recording of the alarm call of a juvenile American Bullfrog jumping from the shore into a small creek in Stanislaus County during daylight (shown to the right.) |
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| Short Video of Alarm Calls | |
| Hundreds of American Bullfrogs make their chirping alarm call as they jump in and out of the water or run across the surface to escape from danger. |
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Encounter Call and Territorial Sounds A male American Bullfrog will make a sharp short call when another male bullfrog gets too close to his territory. American Bullfrogs also make chirping and grinding or rasping sounds when interacting with each other, including their alarm chirp. |
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| This is a short recording of an encounter call heard at night at an irrigation canal in Imperial County where males were calling. Bullfrog advertisement calls are heard in the background. |
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| Short Videos of Territorial Calls | |
| In this very short video, we see a frog make the short sharp territorial call, then jump towards a rival calling male. |
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| American Bullfrogs sitting around a crowded pond interact with each other, making chirping sounds and what appear to be low raspy territorial sounds. |
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Release Call The following sound was made by a large adult female American Bullfrog (shown below) found on a dirt road at night in San Diego County. She was handled for a few minutes after which she began to struggle to escape, making a low growling sound. |
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| This is a short recording of the sound made by a struggling adult female American Bullfrog (shown to the right) when she was handled. |
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Distress Scream When an American Bullfrog is under extreme stress, it may emit a loud open-mouthed screaming sound, which is very disturbing to hear. There is a good Youtube video of a bullfrog screaming here. |
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You can listen to more recordings of American Bullfrogs 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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