American Bullfrog
Lithobates catesbeianus

The American Bullfrog (Lithobates catesbeianus) is probably one of the best known anurans in North America.  It was a wide range across North America, as a native in some areas and an introduced pest in others.

It's call has been various described as resonant "rah-uhm" or as "jug-o-rum".  The general sound of its call is fairly consistent and different than other native species although there is some variation in the type of call, even within a single pond.

Bullfrogs typically call from the shallow edge of a pond.  They are notoriously shy about calling compared to other species and I have had a hard time getting a photo of their vocal sac.  You can just see it extended in this individual.

All of these Bullfrogs were photographed and recorded at a single pond at Aransas National Wildlife Refuge, Texas.

The basic call is a two part "rah-uhm" call  with the first pitch higher than the second -

Although there are variations that have more syllable, some of which can increase in pitch -

© Chris Harrison 2012

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