USGS - science for a changing world

Southeast Ecological Science Center

clear pixel clear pixel clear pixel clear pixel

Giant Toad -  Introduced
Bufo marinus
(click images to enlarge)

GIant Toad - (Bufo marinus) - click to enlarge
Appearance:  Giant Toads range in size from 4 - 6 in. (10 - 15.2 cm).  Females can weigh up to 3.3 lbs (1.5 kg). Giant Toads are huge brown toads that vary in color between brown and red and may have darker and lighter spots/marblings.  Females generally have more patterning that the males. The body tubercles of males are tipped with tiny spines. The distinguishing characteristic of the giant toad is the enlarged parotoid gland.  The immense parotoid glands extend far down the sides of the body.  These glands secrete highly toxic substances that can poison and even kill dogs and other animals that happen to bite into them.

Habitat: In Florida, Giant Toads can be found associated with urban and agricultural areas. This species breeds in canals, flooded ditches, shallow pools and fish ponds.  At night, Giant Toads have been known to congregate around house lights to feed on insects.  They will seek shelter beneath ground debris in dry and cold weather.  Giant Toads are a highly predacious exotic species that will eat all types of native frogs and toads. This species is skilled at locating all types of food, they have even been known to eat dog food.

GIant Toad - (Bufo marinus) - click to enlargeVocalization:  The Giant Toad call is a slow, low-pitched trill that has been compared to the sound of exhaust noise from a distant tractor. The largest males tend to have the deepest voices.

Reproduction/Eggs: Breeding depends on the occurrence of rains, but it may occur from early spring to autumn. A single, large female is capable of producing more than 20,000 eggs. The egg strings may float freely but are more often secured to surface or submerged vegetation.

GIant Toad - (Bufo marinus) - click to enlargeAbundance: The Giant Toad is primarily a native of tropical America.  The Florida population probably results from both introductions and pet trade escapes. The Florida Giant Toads are probably of Colombian origin.  These toads are abundant in Dade and some areas of Monroe Counties.  Giant Toads also occur in lesser numbers in Broward, Glades, Lee, Okeechobee, and Pinellas Counties. For the Florida toads, those in the southern part of the range generally attain a greater size (6 - 7 in.) than those in the northern areas (3 - 4 in.).

Range: Giant Toads range from extreme southern Texas and southern Sonora south to and through the Amazon Basin in South America. Giant Toads are introduced in and around Miami, Florida and Tampa on the Gulf Coast. Giant Toads are also found on Stock Island and Key West.

SE ARMI Index Sites: Everglades National Park, Virgin Islands National Park.



Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo logo U.S. Department of the Interior | U.S. Geological Survey
Page Contact Information: WARC Webmaster
Page Last Modified: Friday, 14-Dec-2012 13:08:46 EST