# American Bullfrog (*Lithobates catesbeianus*)

> The American bullfrog (Lithobates catesbeianus) is North America's largest frog, reaching 9 to 20 cm in body length and weighing up to about 0.5 kg. It lives in and around ponds, lakes, marshes and slow streams, where the male's deep, resonant call carries far across the water. A voracious carnivore, it will eat almost anything it can swallow, from insects to fish and small vertebrates. In the wild bullfrogs live around seven to nine years.

- **Category:** Amphibian
- **Conservation status (IUCN):** Least Concern
- **Range:** Native to eastern and central North America; widely introduced elsewhere as an invasive species.
- **Canonical page:** https://globalanimalguide.org/animals/bullfrog/
- **Last reviewed:** 2026-07-16

## Scientific classification

- **Kingdom:** Animalia
- **Phylum:** Chordata
- **Class:** Amphibia
- **Order:** Anura
- **Family:** Ranidae
- **Genus:** Lithobates

## Facts at a glance

| Attribute | Value |
| --- | --- |
| 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) |

## Size and appearance

The American bullfrog is a heavyweight among frogs, with a body 9 to 20 cm (3.5 to 8 inches) long and a weight of up to about 0.5 kg (1.1 lb). Its skin is olive-green to brownish, often mottled, with a pale, sometimes yellow throat in breeding males. A prominent fold of skin curves around each large, exposed eardrum, or tympanum, which in males is noticeably bigger than the eye. Powerful, fully webbed hind feet make it a strong swimmer and an impressive jumper.

## Diet and feeding

Bullfrogs are ambush carnivores with an enormous appetite and famously indiscriminate tastes. They eat insects, fish and small vertebrates, and larger individuals will take anything they can cram into their mouths, including other frogs, small snakes, mice, and even ducklings. The frog sits motionless until prey comes within range, then lunges forward and engulfs it, using its bulging eyes to help push the meal down its throat. This willingness to eat almost anything has helped it thrive across a wide range of wetlands.

## Movement on land and water

On land the bullfrog travels in long, powerful hops, launching itself with muscular hind legs that let it clear several times its own body length in a single leap. In the water it is an accomplished swimmer, its webbed feet driving it forward with strong kicks and its top speed reaching around 16 km/h (10 mph). When startled at the water's edge it will make a rapid dive, kicking down into mud or vegetation to hide. This ability to both hop and swim lets it move easily between land and water to hunt and escape danger.

## The bullfrog's call

The bullfrog takes its name from the male's deep, booming call, often written as a resonant jug-o-rum that carries far across a pond on warm nights. He produces the sound by pumping air back and forth over his vocal cords while inflating a large throat sac, and the low pitch travels much further than the calls of smaller frogs. Males call to defend territory and to attract females during the breeding season, and a chorus of many bullfrogs can be heard from a considerable distance. Each male's call also signals his size, since bigger frogs produce deeper notes.

## Life cycle and tadpoles

Bullfrogs breed in late spring and summer, and a single female can lay a film of up to twenty thousand eggs across the water's surface. The tadpoles are exceptionally large and can take one to three years to complete their transformation into froglets, depending on climate. During this long larval stage they graze on algae and plant matter before switching to a carnivorous adult diet. Adult bullfrogs typically live around seven to nine years in the wild.

## Frequently asked questions

### How big do American bullfrogs get?

They are North America's largest frog, with a body 9 to 20 cm (3.5 to 8 inches) long and a weight of up to about 0.5 kg (1.1 lb). Females tend to be slightly larger than males.

### What do bullfrogs eat?

Bullfrogs are carnivores with a huge appetite, eating insects, fish and small vertebrates. Large individuals will swallow almost anything that fits in their mouths, including other frogs, small snakes, mice and even ducklings.

### Why are bullfrogs so loud?

Male bullfrogs make a deep, resonant call by pumping air over their vocal cords and inflating a large throat sac. The low pitch carries far across water, helping them defend territory and attract females.

### How long do bullfrogs live?

In the wild American bullfrogs live around seven to nine years. Their tadpoles alone can take one to three years to transform into froglets before adulthood.

### Can bullfrogs jump far?

Yes. Their powerful hind legs let them leap several times their own body length in a single hop. In water they are also strong swimmers, reaching speeds of around 16 km/h (10 mph).

### Are bullfrogs invasive?

Outside their native eastern North America they can be highly invasive. Their enormous appetite and rapid breeding let them outcompete and eat native amphibians where they have been introduced, making them a problem in parts of the western United States and beyond.

## Sources

- [IUCN Red List — Lithobates catesbeianus.](https://www.iucnredlist.org/search?query=Lithobates%20catesbeianus&searchType=species)
- [Animal Diversity Web — Lithobates catesbeianus. University of Michigan Museum of Zoology.](https://animaldiversity.org/accounts/Lithobates_catesbeianus/)

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Source: Global Animal Guide (https://globalanimalguide.org/animals/bullfrog/). Licensed CC BY-NC 4.0 — free for non-commercial reuse with attribution.