In the Northeast, sometime in September or October you realize that you’re no longer seeing American Toads. This is because they are taking steps that allow them to survive over the winter. These steps consist of either finding another animal’s burrow or digging their own (up to 20 inches or so deep) in order to hibernate below the frost line.
As the photograph illustrates, toads dig their tunnels facing forward, using their hind legs to do the digging. Special hardened knobs on their hind feet assist them in this endeavor. As they dig deeper, the tunnel in front of them collapses. When deep enough to hopefully avoid being frozen, they stop digging and hibernate until the soil begins to warm. Come April or May, American Toads dig their way up to the surface of the ground and head for breeding ponds. (Photo by Ashley Wolff)
Frogs and toads that hatched from eggs laid this past spring are now two to four months old, and are growing rapidly. Like snakes, frogs and toads shed their skin as they grow — unlike snakes, they eat their skin. Periodically toads and frogs stretch their bodies and then pull their loosened skin off in one piece, much like we pull off a sweater. Using their feet, they then stuff their skin under their tongue and swallow it. When frogs and toads are young and growing fast, they usually shed their skin more often than when they are older and their growth slows down. Not only is their skin a valuable source of nutrients and protein, but if it’s eaten, there is no sign left behind for predators to find.
Most young toads and frogs, with the exception of the Gray Treefrog, look like miniature adults. (Gray Treefrogs are emerald green in their youth, unlike the mottled gray/green adults they will become.) There is one characteristic at this stage that they don’t share with their elders, however, and that is their snub noses. If you’re wondering if the frog or toad you saw is a small adult or a youngster, take a closer look at its nose! If it’s unusually short and blunt, there’s a bit of growing left to do.
Most of us are familiar with the American toad’s breeding call – a long trill that advertises his presence to potential mates in the area. However, American toads have three other calls, as well. A shortened version of the courtship trill, which sounds like a chirp, is given by male toad with its vocal pouch just slightly inflated. A second, release call, is often heard when a male is clasped by another male. (If you want to hear it, just pick up a male toad during the breeding season – it will vibrate as it chirps right in your hand. The combination of the call and the vibrations usually causes a clasping male to release his grip.) A fourth call, which has been recorded in the lab but not in the field, is a series of quiet clicks given by the male while clasping a female.
Like all amphibians, toads breathe through their skin as well as with their lungs. When a toad is inactive the skin usually absorbs enough oxygen to meet its needs. During and after activity a toad often supplements its supply of oxygen by actively breathing air into its lungs. Unlike mammals, amphibians do not make regular and rhythmic breathing movements but bring air into their lungs spasmodically as the need arises. Air enters the toad’s mouth through its nostrils, and by raising the floor of its mouth, the toad forces the air into its lungs. (Photo is of an American Toad.)