First year: 1957
Established status: Populations are confirmed breeding and apparently self-sustaining for 10 or more consecutive years.
Estimated Florida range: 21 counties At least 10 years, 1 county Not reported breeding
Statewide trend: Unknown status
Threats to natives: Voracious feeders that will prey upon small vertebrates. They will feed on leftover cat and dog food in suburban areas and will even scavenge garbage and discarded vegetable matter (Alexander 1964, Krakauer 1968). Their skin-gland secretions are highly toxic and can sicken or even kill animals that bite or feed on them, including dogs, cats, and native mammals, birds, and snakes. The skin secretions may irritate the skin or burn the eyes of human beings who handle them. They compete with native frogs and toads for food and breeding areas. Consumption of toad eggs causes mortality of tadpoles of other Florida frog species, particularly the green treefrog and southern leopard frog (Punzo and Lindstrom 2001).
Species Account: The giant toad primarily occurs naturally from the Amazon Basin in South America north to the Lower Rio Grande Valley in Texas. The Florida population is probably of Colombian origin and is the result of pet trade escapes and deliberate introductions (Bartlett and Bartlett 1999). In 1936, the University of Florida’s Agricultural Experiment Station released 200 giant toads from Puerto Rico at Canal Point and Belle Glade in Palm Beach County to control sugar cane pests, but the toads disappeared in less than 1 year (Riemer 1958, Krakauer 1968). Two other attempted toad introductions in the 1940s by sugar companies at Clewiston, Glades County, and Pennsuco, Dade County, also failed (Duellman and Schwartz 1958, Riemer 1958, Krakauer 1970). The present population originated from the accidental release in 1955 of approximately 100 toads by an importer at the Miami International Airport (King and Krakauer 1966). These toads spread when a canal was constructed in 1958 linking the Blue Lagoon with South Florida’s extensive canal system. In south Florida populations, female toads are commonly up to 18 cm (7 in) long, but more northerly populations tend to have smaller individuals. The maximum recorded length for the species is 23.8 cm (9.4 in). The ground color varies from red to brown, and there may be a pattern. The immense parotid glands angle downward onto the shoulders and exude a milky white toxin when the toads are attacked. The mating call is a low-pitched, rattling trill that begins with spring rains and is given from canals, flooded ditches, shallow pools, and fish ponds in urban, suburban, and agricultural areas (Bartlett and Bartlett 1999).
Habitats: Exotic plant community, Low density suburban development, areas peripheral to core urban areas, and small towns, Agricultural habitat, Recently disturbed, early successional community, Rockland Hammock