Artwork by

Bullfrog Notecard



Bullfrog (Rana catebeiana)

Bullfrogs are probably the most widely distributed amphibians in North America. They are found across most of the lower 48 states into Mexico, Cuba and Jamaica. Originally, however, they were not native to the western U.S. Bullfrogs may reach up to 8 inches in length. Their overall coloration is green or grey-brown with brown spots. Adults have a conspicuous round eardrum (tympanum) on either side of their head. Even the tadpoles are large; up to 5 inches in length! Bullfrogs may remain in the tadpole stage for as long as two years.

Bullfrogs live in permanent freshwater habitats such as ponds, rivers, lakes or marshes. Chorusing males produce a deep “jug-o-rum” during the day or night; the name “bullfrog” is derived from this bull-like sound. Males establish territories which they defend. Female bullfrogs generally lay eggs only once each year, producing as many as 25,000 eggs each time.

A bullfrog will eat almost anything that moves which it can swallow. They will sit and wait for a meal to pass nearby: insects, spiders and other invertebrates, as well as mice, small turtles, fish, snakes, birds and other amphibians. They have few natural predators, since their toxic skin secretions make them unpalatable to many animals. Where they occur naturally, bullfrogs help keep down mosquito and insect populations. But in some places where they have been introduced their appetite is so voracious that they can destroy local populations of native frog species.

Bullfrogs can live up to 5-6 years. They winter at the bottom of water bodies, burying themselves in the mud.

artwork by John Sill © 2004

text by Steve Sierigk