Fowler's toad (Anaxyrus fowleri, formerly Bufo fowleri ) is a species of toad in the family Bufonidae. It is native to North America, where it occurs in much of the eastern United States and parts of adjacent Canada. It was previously considered a subspecies of Woodhouse's toad (Anaxyrus woodhousii, formerly Bufo woodhousii).
The specific name, fowleri, is in honor of naturalist Samuel Page Fowler (1800–1888) from Massachusetts, who was a founder of the Essex County Natural History Society, which later became the Essex Institute.
Fowler's toad is usually brown, grey, olive green and rust red in color with darkened warty spots. If the toad has a pale stripe on its back it is an adult. The belly is usually uniformly whitish except for one dark spot. The male may be darker in overall color than the female.
The toad is typically 5 to 9.5 cm in length. The tadpole is oval with a long tail and upper and lower fins. It is 1 to 1.4 cm long.
Fowler's toad reproduces in warmer seasons of the year, especially in May and June. It breeds in open, shallow waters such as ponds, lakeshores, and marshes. The male produces a call which attracts not only females, but also other males. The calling male may attempt to mate with one of the other males, which will then produce chirping "release call", informing him of his mistake. When he finds a female the pair will initiate amplexus and up to 7,000 to 10,000 eggs are fertilized. They hatch in 2 to 7 days. Based on observations in Providence Rhode Island Fowler's Toads breed repeatedly through the spring. As many as 10 different age classes separated by several days have been observed over the course of a breeding season in one small pond. A new tadpole may reach sexual maturity in one season, but the process may take up to three years.
Predators of the toad include snakes, birds, and small mammals. It uses defensive coloration to blend into its surroundings. It also secretes a noxious compound from the warts on its back. The secretion is distasteful to predators and can be lethal to small mammals. The toad is also known to play dead.
Fowler's toad lives in open woodlands, sand prairies, meadows, and beaches. It burrows into the ground during hot, dry periods and during the winter.
The adult eats insects and other small terrestrial invertebrates, but avoids earthworms, unlike its close relative, the American toad (Anaxyrus americanus). The tadpole scrapes algae and bacterial mats from rocks and plants using the tooth-like structures in its mouth.
An important conservation measure for the toad is the protection of its breeding sites. Off-road vehicles commonly used in beach and dune habitats are damaging to this species. Agricultural chemicals have caused declines in some areas. It is considered a species at risk in Ontario.