Common name: American Bullfrog

INTRODUCED: Occurs widespread in the Eastern U.S.

Size: 5.12-8.27 in (13.0-21.0 cm)

Distinguishing characters: Largest frog in California; prominent sacral humps; olive, green or brownish dorsum with vague spots or blotches; lighter green head; whitish, grey-mottled venter; legs blotched or banded; conspicuous eardrums; lacks dorsolateral folds.

Juveniles: Similar to adults, but more spotting and more grey on the dorsum.

Dimorphism: Male has yellow throat; eardrum larger than eye; swollen thumb base.

Similar species: none

Additional notes: An introduced species; wary and difficult to capture. Male produces distinctive, deep-pitched vocalizations. Individuals will squawk when jumping into the water to excape. Usually found in association with permanent water, but can disperse over land at least several kilometers. These species require permanent water as their tadpoles over-winter.

Photos by Chris Brown