Toad Identification: Warts, Crests and Parotoid Glands

Most toads in the eastern US are one of three look-alike species, American, Fowler's or southern toad, and they are told apart by five close-up checks rather than by color. Herping Virginia and the Kentucky Organization of Amphibian Watchers (KOAW) use these:

• Warts in the dark spots. American toads usually have fewer warts per dark spot; southern toads often have several enlarged warts per spot (KOAW).
• Calf warts. Herping Virginia calls this the most helpful check: on Fowler's toad the warts on the calf (tibia) are the same size as those on the thigh; on the American toad several calf warts are much larger.
• Cranial ridge and parotoid gland. The parotoid glands are the two large lumps behind the eyes. On Fowler's the ridge behind the eye runs into the gland; on American it misses the gland; southern toads usually have raised knobs on the ridges.
• Belly. Fowler's: plain, with just one dark spot in the center of the chest. American: often dark spots on the chest. Southern: plain and often paler.
• Call. Southern toads trill for about 8 seconds, American toads for more than 11 seconds, and Fowler's gives a groan rather than a trill.

Fowler's toads also have smaller heads and rarely exceed 2.5 inches. Where ranges overlap the species hybridize, so some individuals cannot be named with certainty (Herping Virginia).

Froglife, the UK amphibian charity, separates them this way: frogs have smooth, moist skin and long legs and hop; toads have warty skin and golden eyes and prefer to crawl. A threatened toad can puff itself up to look bigger. Toads also cope better with dry places and spend less time in water. In Britain there are two toads: the widespread common toad, with rough warty skin, golden eyes and two parotoid lumps behind the eyes, and the rare natterjack, smaller, often with a thin stripe down the back, short legs used for short runs, and a very loud call, found only on sand dunes, sandy heath and coastal grazing marshes.

In Florida and South Texas the question that matters most is whether a big toad is a cane toad. Wikipedia describes cane toads as 10 to 15 cm long, occasionally far larger, with distinct bony ridges above the eyes and a large parotoid gland behind each eye. They occur naturally in South Texas, are established in Florida from the Keys to north of Tampa and still spreading, and live in Hawaii. The native southern toad is separated by the pair of raised knobs on its head in front of the parotoid glands (Wikipedia).

Treat every toad as toxic to pets. Pet Poison Helpline states that all toads have skin glands that release toxic chemicals (bufotoxins) when threatened, and names the cane toad and the Sonoran Desert (Colorado River) toad as the two that cause life-threatening signs in pets: severe drooling, difficulty breathing, irregular heart rate, stumbling, seizures and death. Wikipedia describes dogs that mouth a cane toad drooling heavily, with very red gums, head-shaking, crying, loss of coordination or convulsions.

If a dog or cat bites or licks a toad, call your veterinarian or Pet Poison Helpline at (855) 764-7661 ($89 incident fee) right away. If a child mouths a toad or gets its secretion in the eyes or mouth, call Poison Control at 1-800-222-1222. Wash your hands after touching any toad.

A single photo of a toad's back often cannot separate American from Fowler's toad, because the deciding marks are on the head, legs and belly. Take four photos, then let the toad go where you found it:

• Top of the head, showing the ridges behind the eyes and whether they touch the parotoid glands
• The back up close, so you can count warts inside the dark spots
• A hind leg from the side, comparing calf warts with thigh warts
• The belly and chest, for the single central spot of Fowler's or the scattered spots of American

A short audio recording of a calling male settles many cases, since the three species' calls differ in length and sound (Herping Virginia).

Yes. NatureLens identifies toads and frogs from a photo, with free scans every day. For American, Fowler's and southern toads, and their hybrids, confirm the suggestion with the four photos above, because the separating marks are small. Wash your hands after handling any toad, and keep pets from mouthing them.

Research and drafting for this page used AI assistance. Every measurement, date and claim was then checked against the sources listed below, which were opened and read on 2026-09-25. Where two sources give different numbers, both are shown.