The Fowler’s toad (Anaxyrus fowleri) is one of only two toad species in Ontario. People cannot get warts from touching toads. In fact, the bumps on the skin of toads are not warts at all.
The Fowler’s toad is a large yellow, green or brown toad with a light stripe down the middle of the back and large dark blotches, each of which has three or more “warts.” The white belly lacks dark spots. Individuals can grow up to 8.5 centimetres in length. The call of this toad sounds like a crying baby or a nasal “waaa” and lasts about two to five seconds. Listen to the call of the Fowler’s toad (courtesy of Adopt-A-Pond Wetland Conservation Programme).
The Fowler’s toad looks very similar to the American toad. The best way to distinguish these two toads is by counting how many bumps are in each large dark blotch on the back. Fowler’s toads have three or four bumps per blotch, whereas American toads have one or two. The belly of Fowler’s toads tends to be white rather than white with black spots, as in the American toad. These two species can hybridize, making identification more difficult in areas where both may occur. During breeding season, these species can be identified by their calls.
In Ontario, the Fowler’s toad is found in sandy shoreline and peninsula habitat, and is adapted to the early stages of ecological succession in sand dune and lakeshore habitats. They are characteristically unstable, because of fluctuating lake levels and unpredictable floods and storms. These toads breed in backwater marshes and other shallow areas of permanent waterbodies, and may migrate up to several hundred metres between breeding areas and terrestrial habitats.
View an interactive map of the known ranges of Fowler’s toads in Ontario.
Fowler’s toads may begin calling in late April but usually breed in May, when evening temperatures are above 14ºC. Cool weather may interrupt the breeding season, resulting in staggered groups of tadpoles being born, which then complete their metamorphosis at different times during the summer. Each female may lay up to 2,000 to 10,000 eggs. At cool temperatures, tadpole development is a bit slower than that of the American toad. Tadpoles transform into juvenile toads after six to eight weeks. Females mature after two to three years, while males mature more quickly. Individuals up to five years old have been found in the wild.
Both adult toads and their tadpoles have poison glands in the skin that reduce their susceptibility to predators. A dog that picks up a toad will drop it and may foam at the mouth but will not be hurt. These toads eat insects and small creatures that live in soil, such as worms and slugs.
Other names: Bufo fowleri, Bufo woodhousii fowleri
Threats and Trends
The number of Fowler’s toads in a given area can fluctuate tremendously over time, because of the unstable nature of their habitat. Storms can create or destroy breeding habitat, as well as kill individuals. Even without such disturbances, normal ecological succession will slowly degrade a breeding area within five to 10 years. Extensive development of the Lake Erie shoreline leaves little opportunity for storm and flood events to create new habitat. Both adult Fowler’s toads and the tadpoles are known to be sensitive to pesticides, but to what extent these chemicals have contributed to this toad’s decline is unknown.
Current Status and Protection
The Fowler’s toad is currently listed as Endangered under both the Ontario Endangered Species Act, 2007 and federal Species at Risk Act. The species has also been designated as a Specially Protected Amphibian under the Ontario Fish and Wildlife Conservation Act. These acts offer some protection to individuals and their habitat. The International Union for Conservation of Nature lists the global status of the Fowler’s toad as Least Concern. The species’ status was last confirmed in February 2021.
Learn more about reptile and amphibian conservation and what you can do to help these species on our Reptile and Amphibian Stewardship page.
What You Can Do
- Report a sighting
- Get involved in reptile and amphibian conservation on your property, on the road and in your community
- Donate to support reptile and amphibian conservation
- Watch for reptiles and amphibians on the road
- Don’t release pet reptiles and amphibians into the wild
- Read more about the Fowler’s toad in the Ontario Reptile and Amphibians Atlas publication.