American Toad (Anaxyrus americanus): Facts, Call and Habitat

What does an American toad look like?

An American toad has a stout, rounded body, short legs and thick, dry skin covered in warts. Behind each eye sits a large, kidney-shaped parotoid gland, which produces the toad’s defensive toxin. The eyes have horizontal oval pupils and a golden iris, and bony ridges called cranial crests run along the top of the head.

Color varies a great deal. Most American toads are some shade of brown, but individuals can be reddish, olive, gray or almost brick red, often with lighter patches and a pale stripe down the back. Dark spots on the back usually contain just one or two warts each, and these spots may be ringed with white or yellow. The warts on the lower hind legs are noticeably enlarged. The belly is cream or pale yellow, often with dark speckles on the chest.

Toads can lighten or darken their skin with temperature, humidity and stress, so the same animal may look different from one day to the next. Males are smaller than females and have dark throats, especially in the breeding season, while females have pale throats.

American toad or Fowler’s toad?

In much of the eastern United States, the American toad shares its range with Fowler’s toad (Anaxyrus fowleri), and the two can look very similar. The most useful clues are:

• Warts per spot: American toads usually have one or two warts in each dark spot; Fowler’s toads have three or more.
• Belly: American toads usually have a speckled chest; Fowler’s toads have a plain whitish belly, often with a single dark spot.
• Leg warts: American toads have enlarged warts on the lower hind leg; Fowler’s toads do not.
• Head crests: in American toads the cranial crests usually do not touch the parotoid glands, or are joined only by a short spur; in Fowler’s toads they touch.
• Call: a long, sweet trill in the American toad, but a short, nasal “waaah” lasting a few seconds in Fowler’s toad.

The two species sometimes hybridize, so a few toads show a mix of features. For the general differences between toads and frogs, see frog vs toad.

How big do American toads get?

American toads are medium-sized for toads. Most adults measure 5–9 cm (2–3.5 in) from snout to vent, the opening at the base of the body, and the record for the eastern subspecies is about 11.1 cm (4.4 in). Females are larger and heavier than males. Most adults weigh somewhere around 20–50 g (0.7–1.8 oz), depending on size and condition.

The dwarf American toad (A. a. charlesmithi), found in the south-central part of the range, is smaller, reaching about 6 cm (2.4 in), and is often reddish. For comparison, the European common toad can grow larger, with big females reaching about 12 cm (4.7 in).

Where do American toads live?

American toads live across eastern and central North America. Their range stretches from southern Manitoba, northern Ontario and Quebec to the edge of Hudson Bay and Labrador, and south through New England and the Great Lakes states to about northern Georgia, Alabama and Mississippi, reaching west into the Great Plains in states such as Kansas and Oklahoma. They are mostly absent from the warm coastal plain of the Southeast and from Florida, where the southern toad takes their place.

Three subspecies are recognized. The eastern American toad covers most of the range, the dwarf American toad lives mainly in the Ozark region and nearby states, and the Hudson Bay toad (A. a. copei) is a rare northern form known from isolated populations in northern Ontario and nearby areas.

American toads are habitat generalists. They need only two things: shallow, fairly still water such as ponds, ditches, flooded fields or slow stream edges in which to breed, and land with cover and plenty of insects for the rest of the year. As a result they live in deciduous and mixed forests, meadows, farmland, parks, suburban backyards and vegetable gardens, and they are often among the first amphibians people notice near their homes.

What do American toads eat?

American toads are insectivores in the broad sense: they eat almost any small invertebrate that moves and fits into their mouth. Beetles, ants, crickets, moths, caterpillars, spiders, centipedes, slugs and earthworms are all regular prey. Toadlets start with tiny insects and mites, then move on to ants, small spiders and worms as they grow.

Toads hunt by sight and respond mainly to movement. They sit still or creep slowly toward prey, then flick out a sticky tongue that is attached at the front of the mouth and can be extended quickly. Larger prey such as earthworms are pushed into the mouth with the front feet. Toads often wait under porch lights or along paths where insects gather on warm, humid nights.

Tadpoles feed very differently. They graze algae, plant material and organic debris from the bottom and from submerged plants, and only switch to animal food at metamorphosis. More detail on diet is in What do toads eat?

Behavior and daily life

Adult American toads are mostly nocturnal, coming out at dusk and on rainy or humid nights, while young toadlets are often active in daylight. During the day they shelter under logs, flat stones, boards, porches and leaf litter, or in shallow burrows they dig themselves. They are creatures of habit and often return to the same hiding places for weeks.

To dig, a toad backs into loose soil, pushing earth aside with the hard, dark “spades” on its hind feet until only the top of its head shows or it disappears completely. Burrowing keeps the toad cool and moist, since its skin loses water easily in dry air. You can read more in Where do toads go during the day?

In regions with cold winters, American toads hibernate. In fall they dig deeper, below the level the frost reaches, and stay dormant until spring. They do not tolerate freezing in the way some frogs do, so the depth of the burrow matters.

Like other toads, they shed their skin regularly as they grow. The old skin splits and is pulled off in one piece, and the toad usually eats it. American toads move with short hops or a slow walk, in contrast to the fast bursts of hops typical of Fowler’s toad.

Call and breeding

American toads breed in spring, mainly from March to July depending on latitude, with northern populations starting later. Breeding is triggered by warming temperatures, rain and longer days. Males reach the breeding ponds first and call to attract females.

The call is one of the most pleasant sounds of a North American spring: a long, high, steady trill produced by inflating a round vocal sac under the chin. Each trill lasts about 6–30 seconds. Females appear to prefer males that call longer and more often. Males call for only a few nights each, and a chorus may continue for a week or two at a pond.

When a female arrives, a male clasps her from behind in a mating hold called amplexus, using dark nuptial pads on his front toes for grip. As she lays her eggs, he fertilizes them in the water. The eggs come out in two long strings of clear jelly, often wrapped around plants in shallow water, and a single clutch typically holds 4,000–8,000 eggs and sometimes many more. Each tiny egg is black on top and pale below.

Eggs hatch in about 3–12 days, faster in warm water. The small black tadpoles often gather in dense groups in the shallows and complete metamorphosis in about 40–70 days, usually in early to midsummer. Huge numbers of tiny toadlets then leave the water at the same time, sometimes covering paths and lawns around ponds after rain. American toads reach breeding age at about 2–3 years old.

Lifespan

Most American toads never reach adulthood. The great majority die as eggs, tadpoles or newly transformed toadlets, and the average wild lifespan is under a year. Adults that survive can live for several years, and some wild toads are known to have lived about 10 years. In captivity, one American toad lived 36 years before it died in an accident. Our article How long do toads live? compares American and European toads.

Predators and defenses

The American toad’s main defense is chemical. The warts and especially the parotoid glands release a thick, milky secretion containing bufotoxins, which taste bad and can make predators ill. When threatened, a toad may puff up its body, lower its head to point the parotoid glands at the attacker, or play dead. Even the tadpoles are distasteful, and many fish learn to avoid them.

Some predators get around these defenses. Eastern hognose snakes specialize in eating toads and are resistant to their toxins, and garter snakes also take them. Raccoons, skunks, crows and other birds sometimes eat toads, and tadpoles fall prey to aquatic insects such as dragonfly larvae and giant water bugs, as well as to birds.

For people, the toxin is mild. It can irritate the eyes, mouth and other sensitive areas, so it is best to leave toads alone or wash your hands after touching one. More on toad toxins is in Are toads poisonous?

Conservation status

The IUCN Red List classifies the American toad as Least Concern. It has a very large range, a large total population and a high tolerance of farmland and suburbs. Local threats include the loss and drainage of breeding ponds, road traffic during spring movements, pesticides and pollution, and amphibian diseases. In some areas, ponds that dry out too early in hot summers can kill whole cohorts of tadpoles.

Myths and facts

Myth: touching a toad gives you warts. Human warts are caused by a virus, not by toads. A toad’s bumps are glands and thickened skin, not something it can pass on.

Myth: toads are slimy. Unlike many frogs, American toads have fairly dry, leathery skin that feels rough to the touch.

Fact: toads help gardeners. By eating slugs, beetles, caterpillars and other invertebrates night after night, American toads are welcome visitors in vegetable and flower gardens, and leaving some cover and a shallow pond nearby helps them.