If there’s a pond nearby, chances are you’ll find a bullfrog. Bullfrogs are easily recognizable by the sounds they make. The deep calls are reminiscent of the mooing sounds cattle make, which led to them being called “bull” frogs. Although bullfrogs play a beneficial role in controlling mosquitoes and other pests, importing them to other countries has threatened native species of frogs.
Bullfrogs are the largest type of frogs and are found in North America and South Africa. North American bullfrogs also live in other parts of the world, such as Europe and Asia. Bullfrogs aren’t native to these countries and have been imported from North America. North American bullfrogs range in size from 3 ½ to 9 inches and weigh as much as 1.5 pounds, while African bullfrogs weigh as much as 4 1/2 pounds and grow to 9 inches in length or more. Both types of bullfrogs have large heads, strong hind legs and bumpy skin.
North American bullfrogs live in in the warm, shallow areas of freshwater ponds, swamps, lakes or rivers. Animal Diversity Web notes that North American bullfrogs are often found in areas that humans have modified; pollution helps creates ideal habitats for frogs because it can increase water temperature and the growth of aquatic plants. African bullfrogs live on hot, dry grasslands called savannahs. When the savannah is dry, the frogs dig into the soil, where they remain until the rainy season arrives. During the rainy season, the frogs live in flooded areas and puddles. African bullfrogs can remain underground for a year or more, depending on how long the dry season lasts. North American bullfrogs undergo a similar process when they hibernate in the mud during cold winters.
Both North American and African bullfrogs have strong jaws that help them prey on other reptiles. Their mouths are large, enabling them to eat a variety of bugs and animals. Bullfrogs patiently wait for prey to pass by and then use their long tongues to pull their meal into their mouths. A typical bullfrog diet consists of tadpoles, fish eggs, fish, mice, snakes, other species of frogs, insects and birds. Bullfrogs will even eat other bullfrogs and bullfrog tadpoles.
North American bullfrogs were imported from the Eastern United States to various other areas, including California, Europe and Asia, to satisfy the public's desire for frog’s legs, a delicacy on restaurant menus. Bullfrogs were introduced into the wild in these areas by bullfrog farmers. The bullfrogs soon began eating native species of frogs, depleting food sources and spreading disease. The Save the Frogs website notes that bullfrogs can spread chytridiomycosis, a fungal disease that has resulted in the extinction of 100 frog species.
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