American bullfrog

The American bullfrog (*Lithobates catesbeianus*) is a large true frog native to eastern and central North America, including parts of Canada and the United States.

The American bullfrog (Lithobates catesbeianus) is a large true frog native to eastern and central North America, including parts of Canada and the United States. In French, it is commonly called the ouaouaron or grenouille-taureau. It has also been introduced widely outside its native range and is considered invasive in many places.

Description

The American bullfrog is a large ranid frog with a robust body and, in adults, a very large tympanum relative to the eye. Adults are typically green to olive above with a pale belly, and they can grow to about 15–20 cm in body length.

Distribution and habitat

The species is native to eastern North America and occurs naturally in parts of Canada and the United States. It prefers permanent freshwater habitats, especially ponds, lakes, marshes, wetlands, and calm river edges with abundant vegetation.

Behaviour and diet

American bullfrogs are opportunistic predators that eat a wide variety of live prey they can catch. Males produce a loud, low call, especially during the breeding season.

Introduced populations and invasiveness

The species has been moved widely beyond its native range, including to other parts of North America and overseas. In many introduced regions it is treated as invasive because of its ecological impacts.

Name and etymology

The English name comes from the male’s deep call, which resembles a bull’s roar. The French name ouaouaron is of Indigenous origin and is used especially in Canadian French.