Lithobates (Rana) castesbeianus                              Photo Chris Burney ©

The largest native frog in North America, the bullfrog reaches a maximum length of 20 cm (8 in).  Its body is dark olive-green, and the hindlegs may be banded with darker stripes.  On each side of the back there is a prominent ridge that extends from the rear of the eye, over the top of the tympanum (eardrum), and ends above the front leg.  The webbing on the hind foot does not extend to the tip of the longest toe, as it does on pig frogs.

Bullfrogs are found in lakes, ponds and ditches or floating in shallow water.  Breeding begins in April, and eggs often form huge floating rafts of up to 20,000 eggs, which hatch into highly conspicuous and long (7 cm) tadpoles.  The tadpoles do not become frogs until April of the following year.  This may seem like a long time, but Florida bullfrogs actually develop quite fast compared with their northern relatives.  In the northern US, where waters are cooler and the growing season is shorter, bullfrog tadpoles can take 2 years to become frogs.

The bullfrog’s call is a deep, two or three syllable, ‘jug-o-rum’ or simply ‘orum.’

Bullfrogs are found in the northern two-thirds of the state, but are absent from wetlands south of Lake Okeechobee.

top of page | back to frogs / toads