Female North American Bullfrog (Rana catesbeiana) resting in a log in Ludlow, Massachusetts. The Bullfrog is the largest true frog found in North America, weighing up to 0.5 kg and measuring up to 203 mm in length. Typical length ranges from 90 to 152 mm. Color varies from brownish to shades of green, often with spots or blotches of a darker color about the back. The hind feet are fully webbed. During the breeding season the throat of the male bullfrog is yellow, whereas the female's is white. They live in water from Nova Scotia to central Florida, from the East coast to Wisconsin, and across the Great Plains to the Rockies.