American Bullfrog (Lithobates catesbeianus) in the wild — Catch'Um species field guide

American Bullfrog (Lithobates catesbeianus) wildlife photograph

Overview

American bullfrogs are the largest true frogs in North America, inhabiting permanent ponds, lakes, and slow rivers. Males boom a deep jug-o-rum call on summer nights, and adults will eat almost anything they can swallow.

For US collectors, the bullfrog is a common pond giant — booming nights, huge tadpoles, and a familiar — if invasive outside its native East — wetland species.

Scientific nameLithobates catesbeianus
Length9–17 cm body
Weight200–500 g
LifespanAround 7–10 years in the wild
DietAlmost any animal that fits
ConservationLeast Concern
RegionUS Ponds & Lakes

Habitat

Permanent pond
Lake margin
Slow river
Reservoir edge

Permanent freshwater ponds, lakes, reservoirs, and slow streams with vegetated banks across eastern and central North America; widely introduced farther west.

Countries found

American Bullfrog in United States

Field notes

Field scale for the American Bullfrog: length around 9-17 cm body; weight 200-500 g. Typical lifespan: Around 7-10 years in the wild.

When you are scanning habitat, prioritise permanent pond, lake margin, slow river, and reservoir edge. Those settings are where a clean look and a usable photo are most likely.

Quick ID anchor: Large green to brown frog without dorsolateral ridges running down the back. Confirm with behaviour and habitat before you log the discovery.

Diet

Almost any animal that fits — insects, crayfish, fish, frogs, snakes, and small mammals or birds.

Sit-and-wait ambush hunters at the water’s edge.

Behaviour

Males defend calling territories with deep booming choruses.

Mostly aquatic; leap into water when disturbed from the bank.

How to identify

Large green to brown frog without dorsolateral ridges running down the back.

Fold of skin curves from eye around a large tympanum; hind feet fully webbed.

Interesting facts

01
Largest North American true frog — adults often 10–17 cm.
02
Male call is a deep resonant ‘jug-o-rum’.
03
Tadpoles may take 1–3 years to metamorphose.
04
Voracious predators of insects, fish, frogs, and even small birds.
05
Tympanum (eardrum) is larger than the eye in males.
06
Invasive and harmful in many regions outside the native East.

Conservation status

LC: Least Concern

American bullfrogs are Least Concern in their native range and often abundant. Outside that range they are invasive predators that threaten native amphibians and aquatic wildlife.

Sources: IUCN Red List