As the name suggests, the American bull frog hails from America. The bullfrog was originally only found in the central and eastern parts of the US and southeastern Canada, but has now spread to other, more western states. In its native range, the frog occurs in a wide variety of habitats such as swamps, lakes and large river arms, but the species is also common in forests, gardens and parks. The species is strongly bound to water everywhere. Partly because of this, the natural enemies of the bullfrog mainly consist of aquatic animals such as alligators, snapping turtles and American otters. Raccoons have also been observed to eat bullfrogs and their tadpoles on occasion.
An alligator eating a bullfrog
Because of its size, the American bullfrog is considered as a good source for frog legs. Thanks in part to this trade in frog legs and the professional breeding of bullfrogs that accompanies it, the American bullfrog has spread to many other parts of the world. Unnoticed eggs piggybacking with aquatic plants or fish and trading as a curiosity in aquaculture bullfrogs have greatly helped the species’ spread to many other areas. The American bullfrog is currently present in the American archipelago of Hawaii, southern North America (Mexico), South America, Europe and Asia. The map below shows where the bullfrog originates, and in which areas the species is present as an invasive alien species.
The current range of the American bullfrog. Blue zones are considered to be the original, natural range and red zones are areas where bullfrogs occur as an invasive alien species.