Clawed Frogs and Surinam Toads: Pipidae

Clawed frogs and Surinam toads spend much of their time floating in the water with their legs held out from the sides of their bodies. Their dark colors blend in with the water, which makes them difficult for predators to see. They are also quite skittish. The common plantanna, for example, will dive to the bottom of its watering hole as soon as it feels the least bit threatened. Clawed frogs and Surinam toads almost always stay in the water, but sometimes, on very rainy nights, these frogs may leave the water and move short distances from one pond to the next. If they happen to live in a pool of water that dries up during part of the year, clawed frogs and Surinam toads typically bury themselves in the muddy bottom and wait for drenching rain to wet the ground again. This underground waiting period is called estivation (es-tih-VAY-shun). During this time, they do not eat and instead live off fat and other stored energy in their bodies. They may estivate for several months at a time.

Although scientists have not studied these water-loving species very closely, they believe the frogs may mate at any time of year, as long as a heavy rain has soaked the land. Both males and females have the throat disks that allow them to make underwater clicking noises. Each species can make three to six different types of clicks, at least one of which is used to signal that mating time has started. Males climb onto the backs of the females to mate. If a male accidentally climbs onto the back of another male, the second male will click differently to tell the other to get off. As the males and females mate, the females of most species drop their eggs in the water. The eggs hatch into tadpoles, some of which have tiny bits of flesh dangling from the edge of the mouth. These fleshy bits, called barbels (BAR-bulls), are feelers.

Female Surinam toads lay and raise their eggs in a more bizarre way. She flips over while she is laying her eggs, and the eggs settle onto her back, where they stick. Her flesh then swells up around the eggs, turning her back into a sponge-like cradle for them. Depending on the species, the eggs may hatch into tadpoles, or they may skip the swimming tadpole stage and hatch right into froglets. Scientists know this type of back cradle occurs in all but one of the Surinam toads. This is the Myers' Surinam toad, and scientists still are not sure how and where its eggs hatch.