rana toro (Lithobates catesbeianus) is a wild animal medium in size. Its name comes from the noisy sounds similar to a cow. Currently, like the edible frogs, bullfrogs are eaten by humans in parts of North America and are also raised as pets. But they have been introduced in other countries around the world, altering the natural ecosystem by becoming an invasive species that has no natural predators.

Bull frog
Bull frog


The bullfrog is a vertebrate animal, belonging to the group of amphibians. It is the largest in North America, measuring from 10 to 17,5 cm to about 46 cm and its larvae range from 15 to 18 cm. Some specimens weigh 1 kg. Their color varies from brown to different shades of green and they frequent darker colored spots or patches on the back.

It has a broad, flat head and a fold of skin on both sides that runs from behind the eye to the eardrum, bordering it. The eardrum of the male has a greater diameter between the eye and has a dark border, the female is the same size as the eye. The toes of its hind legs, except for the fourth (toe) have interdigital webs.

It is an extremely resistant amphibian and can live up to 10 years in the wild. Some bullfrogs in captivity have reached the age of 16.


The bullfrog is of daytime habits. They can be extremely aggressive, so it is a very dangerous animal for other weaker species. Males have been observed to have three types of vocalizations. Territory calls are used to threaten other males invading the territories of other males. You can also hear calls to attract females in mating season and calls to provoke combat with other individuals.


It can be found in many areas of high non-salt water temperatures such as lagos, swamps or ponds, as it prefers to be in closed waters.


The bullfrog is a carnivorous amphibian and night hunter, which means they are very active at night. They hunt a wide variety of insects (including their larvae and their eggs) Spiders y small fish. While they are tadpoles they feed on various aquatic plants, small vertebrates and detritus.


The bullfrog has many predators in its natural habitat due to its size and noise. Its most common predators are aquatic animals incluyendo big fish, river turtles y snakes.


The bullfrog is an oviparous animal. The breeding season begins in late spring and early summer, when the frogs begin to court the females. Once mating is complete, the females lay around 20.000 eggs that float together on the surface of the water.

In less than a week, the eggs of the bullfrog hatch thousands of tadpoles emerge in the adjacent water. Their limbs begin to develop and begin to look like adult frogs. The whole process can take 3 to 3 years, depending on where the frog develops.

State of conservation

The bullfrog is marked Least Concern (LC) because its native populations have not been threatened and growth of these has also been detected.

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