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Named for its distinctive, loud call, the bullfrog is an aquatic frog belonging to the Ranidae family.


The bullfrog is the largest North American frog, commonly weighing up to one pound and measuring more than 8 inches in length. Bullfrogs are green or brown in color with a white or yellow belly and dark legs.

One of the most powerful features of this large frog is its legs. Commonly measuring 2 inches longer than its body, the bullfrog's powerful, muscular legs are often 10-12 inches long. It is these legs that keep the bullfrog mobile, allowing him to swim, run, walk, or jump. It is not uncommon for bullfrogs to leap 3-6 feet at a time when moving.

This frog is known for its voracious appetite. Bullfrogs do not have a special diet and will most often eat almost anything that moves and that they can swallow. Invertebrates, small vertebrates, birds, reptiles, fish, turtles, and other frogs are all common prey of the bullfrog. There are very few things the bullfrog cannot eat, thanks to its unique mouth and tongue. The bullfrog's teeth are located in the roof of its mouth, which allows it to trap prey. The long, muscular tongue of the bullfrog can effortlessly flip large prey into its mouth in milliseconds, where the prey is then chomped upon with the frog's sharp teeth.

Bullfrogs are territorial and work hard to protect their space. Loud calls, physical displays, chases, attacks and wrestling maneuvers are all tactics used by the bullfrog to claim, keep, and protect its territory. Female frogs are most often attracted to males who live in territories that provide the most food.

The bullfrog has no natural predators, thanks in part to the toxic secretions its skin produces when touched, and animals that manage to capture the bullfrog often release them due to the unpleasant taste. Coupled with the strength of its long legs, the bullfrog very often never concerns himself with danger.

The most important sense to a frog is hearing. Male bullfrogs often chorus at breeding ponds for several hours a night. Female frogs give reciprocal, aggressive calls, as well. Frogs use their incredible hearing to avoid capture, to listen for other frogs moving into their territory, and to protect their young.


In many areas of the United States, bullfrogs help to keep populations of insects in check. Those states with unusually high volumes of mosquitoes will often ship in bullfrogs, which they add to waterways, rivers, streams, and lakes to help control overgrowth.


The female bullfrog can lay as many as 25,000 small eggs in a day. After breeding in the spring, the adult female releases the eggs in the water to hatch into dark, greenish brown tadpoles. This cluster of eggs remains together at the surface of the water until they metamorphize. Unlike other frogs, growth and development of the young bullfrog is unusually slow. Bullfrog tadpoles often remain in the tadpole stage for up to 3 years, depending on the climate. Those that remain tadpoles the longest most often grow to be larger in size.


The population of the bullfrog has never been a concern. This aggressive frog cares for itself quite well and has never been in danger of extinction. Today, the bullfrog is used in several countries to test medical drugs and procedures, and control insect population. The bullfrog is also a common pet. Several Southern states and parts of Asia still consider frog legs a delicacy, and in these parts, the bullfrog is actively hunted, bred, and fished.