Frog of the Week

American Bullfrog (Rana catesbeiana)

American Bullfrog

Common Name: American Bullfrog
Scientific Name: Rana catesbeiana
Family: Ranidae – True Frog family
Native Locations: Canada, Mexico, and the United States of America
US State Locations: Alaska, Alabama, Arkansas, Arizona, California, Colorado, Connecticut, District of Columbia, Delaware, Florida, Georgia, Hawaii, Iowa, Idaho, Illinois, Indiana, Kansas, Kentucky, Louisiana, Massachusetts, Maryland, Maine, Michigan, Minnesota, Missouri, Mississippi, Montana, North Carolina, Nebraska, New Hampshire, New Jersey, New Mexico, Nevada, New York, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Utah, Virginia, Vermont, Washington, Wisconsin, West Virginia, and Wyoming
Introduced Locations: Argentina, Belgium, Brazil, China, Colombia, Cuba, Dominican Republic, Ecuador, France, Germany, Greece, Haiti, Indonesia, Italy, Jamaica, Japan, Malaysia, Peru, Philippines, Puerto Rico, Singapore, Spain, Taiwan, Thailand, Uruguay, and Venezuela
Size: Females: 4.7 – 7.2 inches (120-183 mm); Males 4.3 – 7 inches (111-178 mm)

The American Bullfrog is one of the largest frogs in the world. This has lead to it to being one of the most devastating invasive frogs in the world. The frogs are naturally found in North America but has spread to South America, Europe, and Asia. Their large size gives it an advantage over other frogs when it comes to catching prey and they also just eat other frogs. Invasive American Bullfrogs also can spread diseases and viruses.

Reproduction of the American Bullfrog

In its natural range, the American Bullfrog is one of the last frogs to come out of hibernation. It is also the last to start breeding. Their call is very noticeable and is one of the common sounds of the swamp.

The Bullfrog breeds in permanent bodies of water such as lakes and ponds. Males will select territory in the shallows of those water bodies. The females select a male to mate with, generally selecting the largest, oldest males. The male frogs have bright yellow throats, while the females have white throats. The male will grasp the female from behind the amplexus position. Then, the female will lay up to 20,000 eggs and the male will fertilize them. Neither parent will provide any care for the offspring.

The time it takes for the tadpoles to complete their metamorphosis vary. In the south, the tadpoles can complete their metamorphosis in 3 months. In the far northern part of their range, it can take 3 years!

The International Union for the Conservation of Nature (IUCN) Red List assesses the frog as Least Concern for Extinction. The bullfrog has a huge range that is expanding across the globe so it is not in danger at all of becoming extinct.

72 thoughts on “American Bullfrog (Rana catesbeiana)”

Leave a Reply