American Bullfrog

Media
Image of American Bullfrog
Scientific Name
Lithobates catesbeianus (formerly Rana catesbeiana)
Family
Ranidae (true frogs) in the order Anura (frogs)
Description

The bullfrog is Missouri’s largest frog; it ranges from green to olive to brown. The back may have small brown spots or dark, indistinct, irregular blotches. The hind legs are marked with distinct dark brown bars. The belly is white, and the throat may have some gray mottling. The external eardrum is large and round. On adult males this tympanum is much larger than the eye; on females, it’s about the same size as the eye. This species has been known to reach 8 inches from snout to vent. Call is a deep, sonorous “jug-a-rum, jug-a-rum” that can be heard from half a mile away or more.

Size
Length (snout to vent): 3 to 6 inches.
Where To Find
American Bullfrog Distribution Map
Statewide.
The bullfrog is our most aquatic species of frog. Individuals spend most of their time in or very near lakes, ponds, rivers, large creeks, sloughs, and permanent swamps or marshes. Because permanent water is required, bullfrog populations can suffer during drought years. When disturbed, bullfrogs escape by powerful jumps into the water. Young bullfrogs will often give out a short, high-pitched yelp as they leap to safety. Bullfrogs sometimes move overland during heavy summer rains.
Bullfrogs will try to eat just about any moving creature they can get their mouths around. The size and age of the frog, the season, and the type of habitat influence their diet. Frogs in farm ponds have different foods available than ones in impoundments or in rivers. In general, foods include insects, spiders, crayfish, fish, amphibians, birds, and even small mammals. Bullfrogs commonly eat other frogs, and they don’t hesitate to eat their own kind.
Common. The American bullfrog is a game animal in Missouri and is protected by a season and bag limit. Consult the Wildlife Code of Missouri for regulations.
Life Cycle
In Missouri, bullfrogs are active from late March to October. To overwinter, they burrow into bottom mud of rivers or ponds. Breeding is in mid-May to early July. Males are highly territorial and physically aggressive to each other as they defend calling stations. Eggs are laid in shallow water in a wide, floating mass. Females can lay over 20,000 eggs per clutch; these hatch in 4–5 days. Tadpoles turn into froglets in about 11–14 months, but adult size isn’t reached for another 2–3 years.
The bullfrog is the official Missouri State Amphibian. The legs are edible and considered by many to be a delicacy — which in common language means “good eating!” Bullfrogs are classed as game animals in Missouri and are protected by a season and bag limit under the state’s Wildlife Code.
Although these large, powerful amphibians will gulp down practically any creature that will fit in their mouths, they also become food for many other organisms. Even if female bullfrogs lay about 20,000 eggs, most of the eggs, tadpoles, and froglets are chomped by other animals.
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Where to See Species

The Conservation Department purchased 366 acres in 1965 to preserve unique wetlands and habitats associated with the Missouri River and to provide public lands and recreational opportunities in northw
This area which was named for the late Robert A. Brown, a St. Joseph conservationist, consists of 3,307 acres of bottomland and is bounded by the Missouri River for three miles.
About Reptiles and Amphibians in Missouri
Missouri’s herptiles comprise 43 amphibians and 75 reptiles. Amphibians, including salamanders, toads, and frogs, are vertebrate animals that spend at least part of their life cycle in water. They usually have moist skin, lack scales or claws, and are ectothermal (cold-blooded), so they do not produce their own body heat the way birds and mammals do. Reptiles, including turtles, lizards, and snakes, are also vertebrates, and most are ectothermal, but unlike amphibians, reptiles have dry skin with scales, the ones with legs have claws, and they do not have to live part of their lives in water.