An American bullfrog photographed at Denver Zoo in Colorado
An American bullfrog photographed at Denver Zoo in Colorado
The baritone call of the bullfrog is so deep and resonant, it resembles the mooing of a cow, hence its name. Only males emit this trademark "jug-o-rum" bellow, and their choruses can be heard during the day or night.
The largest of all North American frogs, this giant can grow to a length of 8 inches or more and weigh up to 1.5 pounds. Even the tadpoles of this species can reach 6.75 inches in length.
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