Size: 9 to 20.3 cm long (3 ½" to 8") (largest frog in N. America)
General Description: Skin plain green to yellow or gray or with random or netlike darker mottling. Large tympanum. Cream to white or yellowish, often with gray mottling on belly. Patterning tends to be heavier or darker in southeastern part of range. No dorsolateral ridges on trunk of body but may have ridges near eardrum. Hind feet fully webbed except for last joint of longest toe.
Similar Species: Green and Bronze Frogs, R. clamitans and R. clamitans clamitans, are differentiated by the presence of their dorsolateral ridges. River Frog, R. heckscheri, has light spots along its jaw producing a scalloped effect on its lips. Pig Frog, R. grylio, has webbing to the tips of the toes on its hind feet, compared to the Bullfrog which has less extensive webbing and the longest toe (4th toe) tip extends beyond the webbing.
Reproduction: Breeds February to October.