American Bullfrog
Lithobates catesbeianus
Quick answer
The American bullfrog is the largest frog native to North America, reaching up to 20 cm (8 in) long and weighing around 0.5 kg (1.1 lb). Named for the deep, resonant call of breeding males, it is a voracious ambush predator that will eat almost anything it can swallow. Bullfrogs typically live 7 to 9 years in the wild.
American Bullfrog facts at a glance
| Scientific name | Lithobates catesbeianus |
|---|---|
| Diet | Carnivore (insects, fish, small vertebrates) |
| Habitat | Ponds, lakes, marshes, slow streams |
| Lifespan | 7–9 years in the wild |
| Weight | Up to 0.5 kg (1.1 lb) |
| Size | 9–20 cm (3.5–8 in) body length |
| Conservation status | Least Concern (IUCN) |
| Kingdom | Animalia |
|---|---|
| Phylum | Chordata |
| Class | Amphibia |
| Order | Anura |
| Family | Ranidae |
| Genus | Lithobates |
Where it lives
Native to eastern and central North America; widely introduced elsewhere as an invasive species.
Behavior and calls
Male bullfrogs are best known for their loud, low-pitched 'jug-o-rum' call, used to defend territory and attract mates during the warm breeding season. They are mostly active at night and spend the day floating among vegetation or resting at the water's edge. Bullfrogs are powerful jumpers and strong swimmers, diving quickly when threatened.
Diet and feeding
Bullfrogs are sit-and-wait ambush predators with enormous appetites. They eat insects, worms, fish, crayfish, small snakes, rodents, and even other frogs, lunging with a sticky tongue and swallowing prey whole. If it moves and fits in their mouth, a bullfrog will usually try to eat it.
Habitat and range
Native to eastern and central North America, the American bullfrog lives in warm, still or slow-moving freshwater such as ponds, lakes, and marshes. It has been introduced to many regions worldwide, where it often becomes an invasive species. Tadpoles can take one to two years to fully transform into adults.
Conservation
The American bullfrog is listed as Least Concern and remains abundant across its native range. Outside North America, however, introduced bullfrogs threaten native amphibians by preying on them and spreading disease. In its homeland it is hunted both for sport and for its edible legs.
Frequently asked questions about the American Bullfrog
How big do American bullfrogs get?
American bullfrogs can reach about 20 cm (8 in) in body length and weigh up to 0.5 kg (1.1 lb), making them the largest frog native to North America.
What do bullfrogs eat?
Bullfrogs are carnivores that eat almost any animal they can swallow, including insects, worms, fish, crayfish, small snakes, rodents, and even other frogs.
Why are bullfrogs so loud?
Male bullfrogs produce a deep, carrying 'jug-o-rum' call to defend their territory and attract females. The sound is amplified by a large vocal sac and can be heard from a long distance.
How long do bullfrogs live?
In the wild, American bullfrogs usually live about 7 to 9 years. In captivity, with steady food and no predators, they can live longer.
Are bullfrogs invasive?
Yes, outside their native North American range. Introduced bullfrogs are considered invasive in many parts of the world because they outcompete and prey on native amphibians and can spread disease.
