The Arizona toad, or anaxyrus microscaphus, is an amphibian native to the southwestern United States. It is found in Arizona, New Mexico, Utah, and Nevada. Arizona toads have one pale stripe across the head and are usually gray, green, or brown with smooth, warty skin and pale bellies. Coloration of this toad varies depending on the location, helping it to blend into its surroundings. The Arizona toad reaches a length of 2 to 3.25 inches (5 to 8.25 centimeters) at maturity, and the tadpoles are around 1.5 inches (3.8 centimeters) long.
These amphibians prefer water courses in rocky terrain and spend their lives near the water. They are found in canyons, freshwater marshes, and flood plains. The Arizona toad also frequents irrigated fields, washes, and watery ditches. It prefers spaces open to the sky without dense tree cover.
Arizona toads breed in slow-moving water and side pools. The males croak out a call to attract females. If there is no response, the male Arizona toad may snatch a female that goes by. Breeding can take place anytime between February and July, depending on the temperature and elevation.
Females lay clutches of approximately 3,000 to 4,000 eggs along the edges or bottoms of shallow pools and streams. Most eggs hatch successfully after around 3-6 days, and the young remain in the tadpole stage anywhere from 1 to 4 months. Almost 100% of the hatchlings survive and undergo metamorphosis.
The tadpoles subsist on a diet of plants, while the adult toads are mostly carnivorous and thrive on snails and insects that they catch by flicking out their long, sticky tongues. Tadpoles and young toads are more active during the day, and then become mostly nocturnal as adults. The toads commonly move by hopping, although they sometimes navigate with a slow walk or crawl. Adults generally spend the days underground, venturing out only to seek mates and breed.
Many children like to catch frogs and toads, but the Arizona toad is one amphibian that they should avoid handling. It has glands behind the eyes capable of excreting a poisonous fluid. When this poison touches the mucous membranes of the mouth, it can cause nausea, inflammation, irregular heartbeat, and can sometimes be fatal.
Although most Arizona toads survive metamorphosis, their numbers decrease afterward due to predation by birds, snakes, raccoons, and other small mammals. Habitat loss due to human development can also decrease a local population of the Arizona toad. There is no scarcity of this toad, however, and it doesn’t appear on any endangered species lists.