Boundary Invasive Species Society
American bullfrog
(Rana catesbeiana)
There are no known infestations of American bullfrogs in the Boundary. There have been reports in the Okanagan, Central Kootenay and in Northern Idaho. There are a lot of bullfrogs at the coast.
Identification:
Impacts:
Bullfrogs are very large, robust, green or brown in colour with large golden eyes. Adult female Bullfrogs may reach 20 centimeters in length (not including legs!) and 750 grams in weight. Male Bullfrogs are somewhat smaller. Both sexes have a large and distinct tympanum (‘ear’) just behind and below the eye. The tympanum is partly surrounded by a fold of skin that runs from the eye down to the shoulder. Males have a tympanum roughly twice the size of the eye, while females have a smaller tympanum that is about the same size as the eye. The sexes may also be distinguished by their throat colour – males have yellow throats, often quite bright, while females have paler cream or white throats.
Bullfrogs will eat anything that they can fit in their mouth; including snakes, baby turtles, birds, fish and other frogs. They are aggressive predators and they have huge impacts on native animal populations.
Prevention:
You can help native frogs by not transporting Bullfrogs from one pond to another. The large tadpoles are tempting ‘pets’ for children or for gardeners who want some life in their backyard pond, but this kind of bucket-brigade transport seems to be one of the primary ways that Bullfrogs are spreading in the province. Bullfrogs are considered wildlife in B.C., and it is actually illegal under the Wildlife Act to capture, transport, keep or sell them.Please report it if you think you have seen or heard bullfrogs.