American Bullfrog

swimming american bullfrog, shown under GNU Free Documentation License

The bullfrog is a type of “true frog”. It is a member of the family Ranidae. When one says bullfrog, it usually means the American bullfrog. The bullfrog is named as such because their deep and loud croaks make them seem larger than they are. These large croaks are used to keep enemies at bay and help them survive the wild.

But this does not mean the bullfrog is a tiny delicate frog. In fact, the bullfrog is a humongous species. The bullfrog's body length ranges from around three to six inches with the legs adding around seven to ten inches more to the size of the frog. This leg length does not go to waste because these frogs could jump an astonishing length of three to six feet. This might not sound impressive, but take your one foot ruler and measure six of those on the floor to see the leaping prowess possessed by the bullfrog.

Bullfrogs could weigh up to one and a half pounds. Females, of course, are larger than their male counterparts. They generally sport earth colors such as brown and green with yellow, black or brown blotch accents on their underside. Studied carefully, a bullfrog's skeletal system consists of hyaline cartilage, calcified cartilage and bones. The calcified cartilage part is most pronounced in the epiphyses of some parts of the bullfrog. However, it is also present all throughout their skeleton.

The reason why bullfrogs are such powerful jumpers is because they have neither scapula nor suprascapula. This makes them extra agile. Like every frog, the end of the spinal column is the urostyle, which is a bump visibly present at the posterior part of frogs.

Bullfrogs, like all other frogs, breathe through cutaneous exchange. This means they not only use their buccal cavities and lungs to breathe but also their skin. Males have testes and ducts while females have ovaries which are used for reproduction. When sexually mature, a bullfrog can lay up to 25000 eggs that are laid right beneath the surface of the water. Of course, this only happens after intense courtship.

Males of the species tend to aggregate in ponds and croak simultaneously. Females answer to mating calls in the same aggressive manner. Females tend to choose partners depending on the amount of food accessible in a male's territory.

When the eggs hatch, they of course become tadpoles. These tadpoles which are quite large (around a hand's length in size), would then undergo subsequent changes -- premetamorphosis, prometamorphosis and finally, metamorphosis. Premetamorphosis is when an embryo develops and no thyroid gland is existent. Prometamorphosis is when the thyroid gland begins to form. Metamorphosis is the final stage wherein the tadpole tail and the gills are absorbed into the body and the frog innards undergo certain changes to ready the bullfrog for maturity. This cycle could last for one to two years. It might sound long but the longer a frog is in the tadpole stage, the better. It is perceived that those who transform later on are bigger, stronger bullfrogs. Bullfrogs could live more than a decade (around 13 to 14 years).

Feeding and Care

Bullfrogs are rapacious eaters. Their range of menu includes big insects, worms, other frogs, small birds, mammals, reptiles, and fish among many others. They have a sticky retractable tongue used to snatch prey into their mouths wherein a sharp row of teeth are used to trap prey. Feeding bullfrogs is as easy as leaving some live food on rocks or patches of earth on the habitat. Bullfrogs also have the tendency to cannibalize, so it is best to never raise more than one bullfrog inside a tank.

When raised in captivity, all the bullfrog needs is what the other members of the true frog group needs. Water and soil should be present in an aquarium setup with the water able to cover around half of the bullfrog's size while the soil should be enough to cover the frog when it wants to hide. Other hiding places such as logs, rocks and substrate should also be present. Because of their big appetite, insect infestation might never be a problem for an area with a healthy population of bullfrogs.

The scientific name of the American bullfrog is Rana catesbeiana. The tympanum or the ear drum of the female species is similar in size with their eyes. The males, however, generally have larger ear drums.

Back to the setup, temperature levels should be kept between 25-28 degrees Celsius. They should also be kept in a humid environment hence a humidifier would be in effect during some days of the year. American bullfrogs are native to the United States and are predominantly present on the eastern part of the country. In the wild, they tend to live beside bodies of water.