|A Fowler's Toad (Bufo fowleri) surprised me while I was walking along a sandy and rocky beach on the Little Miami River.|
I soon found out there were three Fowler's Toads hiding out in the sand and rocks. One was large, one medium, and one small. The smallest toad was young, and the white stripe that went down his back was barely visible, but other than that, all three had distinct markings. Fowler's Toads and American Toads (Bufo americanus) look a lot alike, but if you examine the "warts" in the largest dark spots on their backs you can tell them apart. Fowler's Toads usually have three or four warts per spot, while American Toads usually have only one or two...
|This toad had four "warts" in each of his larger dorsal spots, so I knew he was a Fowler's Toad (Bufo fowleri).|
Another way to tell the two toads apart is to look at their bellies. Fowler's Toads have mostly white bellies with a dark spot in the center...
|I laid down on the rocks so I could get a look at this fellow's belly. Sure enough, it was mostly white with a central pectoral spot. Again, confirmation that he was a Fowler's Toad. American Toads have a lot of dark spots on their bellies.|
...another way to distinguish a Fowler's Toad from an American Toad is to check the warts on their hind legs. On a Fowler's Toad, the warts on the tibia are usually just a little larger than those on the thigh and foot. On an American Toad, the tibial warts are a lot larger (source: "Amphibians & Reptiles of Indiana," Sherman Minton, Jr., pg 112)...
|...the tibial warts are just a little larger than those on the thigh and foot. Another clue points to a Fowler's Toad!|
The warts on a toad aren't warts at all. They are tiny glands that secrete a liquid toxin that burns the lining in the mouths of predators that try to eat them! The large bumps behind the toad's eyes are called parotoid glands, and they can secrete a lot of the toxin at once, causing the predator to drop the toads quickly. The toxin is strong enough to kill a dog that bites into them, but the toxin can't harm humans if it's secreted on the hands (source: "Amphibians of Ohio Field Guide" Division of Wildlife, pg 28 and Fast Facts).
Last year when I photographed an Eastern Hognose Snake going through all his antics (click here for that post), I remember reading that hognose snakes (whose favorite food is toads) are immune to toads' toxins.
p.s. A reader wrote me about an encounter he had with a toad, and it's a good warning. While sleeping a toad landed on his chest. Startled, he knocked it off. He then rubbed his eyes and started to go back to sleep. Suddenly it felt like his eyes were on fire, and they started watering like crazy! The toxin really can burn your eyes, so always wash your hands after handling a toad... (Thanks for letting us know, Robert!)