American Bullfrog (Rana catesbeiana)
What do they look like? Bullfrogs are typically green or greenish brown, and can be a light or dark shade. The back and sides may be plain or may have dark spots. The arms and legs are spotted or barred with dark. Underparts are white, distinctly or obscurely spotted and mottled.
The bullfrog is a powerful swimmer, with strong, long back legs that may measure from seven to ten inches and having very large webbed feet.
Both male and female bullfrogs can reach a body length of 6 to 8 inches. A bullfrog's head is broad and flat. The eye color is either golden or reddish bronze (see photo).
How can you tell a male from a female? The male and female bullfrogs are distinguished by the size of the external eardrum (tympanum). The female's eardrum is approximately the size of the eye, while the male's is much larger than the eye.
The sexes may also be distinguished by their throat color – males have yellow throats, often quite bright, while females have paler cream or white throats.
Take a close look at the top photo. Is this a male or a female bullfrog?
Where do they live? Bullfrogs range naturally from the eastern to central U.S., north to Nova Scotia, and south to Mexico.
In Washington, this frog is an introduced species commonly found in many lakes, reservoirs and sloughs. It is highly aquatic and stays close to the borders of lakes. Its spread throughout Washington State may be due more to illegal releases and floral nursery sales for insect control that its ability to spread on its own.
What do they eat? Carnivore. They like to eat crayfish, water beetles, snails and dragonfly larvae. The also eat fish, small turtles, young water birds, and even other frogs!
Reproduction: The bullfrog is generally a solitary animal except during breeding season which runs from late May into July.
Large bullfrog tadpoles can be found any month in the year, but June and July are when the final transformations are made. Bullfrog tadpoles do not develop into frogs during the first season, as do those of the leopard frogs. It is not until the second season, and sometimes the third, that a bullfrog tadpole makes its final transformation.
Behavior: Adult bullfrogs can generally leap about 1 meter (3 ft), but they are able to jump a distance of 2 meters (6 ft) without difficulty.
Did you know?
Animal silhouettes available to purchase »
Photo Credit: Natures Pics
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