Physical Characteristics, Behavior, and Life Cycle

American toads are common throughout most of Iowa, with the exception of the far-western counties, where their preferred habitats are less abundant.​

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Adults have a short, squatty appearance and typically measure between 2 and 3.5 inches in length. Color varies, but American toads are most often brown or gray, with occasional olive, tan, or reddish hues. Males have a dark throat during the breeding season, while females have a lighter throat and are larger overall.

Their backs are covered with dry, rough skin and dark spots, each typically containing one or two prominent warty-looking glands. Their bellies are creamy, white, or yellowish and marked with dark grey or black spots. Coloring can change depending on temperature, humidity, and stress.

After spending the winter underground in a state called brumation (similar to hibernation), American toads emerge as early as April in Iowa. They head straight for fishless water sources, where males begin their evening serenades. During the breeding season, which runs from April to June, males produce a long, high-pitched musical trill that lasts 5 to 30 seconds. Some say the call sounds like a whistle blown underwater. When many males sing together, their calls create a harmonious chorus. For reference, Jeff LeClere at HerpNet offers a video featuring a male American toad singing, with other males joining in the background.

Females, attracted by the calls, lay between 2,000 and 20,000 eggs in long gelatinous strings, which can be up to several feet in length. The male fertilizes the eggs externally after latching on to the female. Eggs hatch in 3–12 days, and tadpoles transform into tiny toads in 40–70 days. By mid to late summer, juvenile toads emerge onto land and feed on insects for the remainder of the season.

In summer, American toads are most active at night when the weather is warm and humid. While adults are more terrestrial after breeding, they still require access to moist environments, such as damp soil or shallow water sources, to prevent dehydration. They do not drink water from their mouths but absorb it through their skin.

Toads are voracious eaters, consuming a wide variety of invertebrates, including ants, snails, slugs, earthworms, beetles, and moths.

When temperatures cool, toads burrow below the frost line using their hind legs and produce natural “antifreeze” compounds to survive harsh winters.