American bullfrog
American bullfrog (Lithobates catesbeianus)
Illinois Status: common, native
Features and Behaviors
FEATURES
The American bullfrog averages three and one-half to six inches in length. It lacks dorsolateral folds on the back. The webbing on its feet extends to the toe tips. The body is brown, olive or green with dots or blotches. The tympanum (eardrum) is wider than the eye in males and nearly the same size as the eye in females. The vocal pouch is in the middle of the throat.
BEHAVIORS
The American bullfrog may be found statewide in Illinois. It lives in lakes, rivers, marshes, ponds and creeks. The adult bullfrog is solitary and wary. It is usually found at the water’s edge. Breeding occurs from late April through August. The male’s call is “jug-o-rum” or “br-wum.” A male will defend its territory from other male bullfrogs. The female deposits about 20,000 eggs in water. Hatching occurs in less than a week. Tadpoles metamorphose (change to the land-based form) after about 14 months. Tadpoles may grow to more than six inches in length. The bullfrog eats almost any living thing that it can catch and swallow, although crustaceans and insects make up most of the diet.
Illinois Range
Taxonomy
Kingdom: Animalia
Phylum: Chordata
Class: Amphibia
Order: Anura
Family: Ranidae
Habitats
Aquatic
bottomland forests; lakes, ponds and reservoirs; Lake Michigan; marshes; peatlands; rivers and streams; swamps; wet prairies and fens
Woodland
bottomland forests; southern Illinois lowlands
Prairie and Edge
black soil prairie; dolomite prairie; edge; gravel prairie; hill prairie; sand prairie; shrub prairie