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.