Shovel-Nosed Frogs: Hemisotidae

The strong body, muscular legs, heavy skeleton, and shovel-like snout together help these frogs to be excellent diggers. They all dig head first into the muddy banks near water pools or small ponds, moving the head up and down to take advantage of the "shovel nose" to push away soil. Even the tubercles on the heels of their hind feet give them an added push when they are forcing their front ends into the ground. Most other burrowing frogs use their rear legs as the main digging limbs and dig themselves backward into the soil. During the dry season of the year, the frogs stay in their burrows and rest. This resting period during dry weather is called estivation (es-tih-VAY-shun). When the rains come, the frogs come out to look for food or to mate.

When the mating season starts, the males call to attract females. They call from the ground in a hiding spot under plants next to a pool of water or small pond. The call is a long buzzing sound. The call of a male marbled snout-burrower, for instance, is a buzz that lasts about two seconds. When a female pairs up with a male, he crawls onto her back and holds on as she starts digging head first into the ground to make a burrow under a log or stone. With the male still on her back, she continues tunneling. When the pair are completely buried, she lays a clump of one hundred fifty to two hundred eggs, although some females only lay about three dozen eggs. Each egg is about 0.1 inches (2 to 2.5 millimeters) in diameter and has a capsule around it.

After mating, the male digs back out of the ground and leaves, but the female stays behind with her eggs. As the eggs develop, rains continue to fall, eventually filling the pools and ponds. Water overflows and soon rises to cover and soak into the underground chamber where the female is staying with her eggs. By this time, usually less than two weeks later, the eggs begin to hatch into tadpoles. The female may dig a tunnel out of the burrow. The tadpoles use the tunnel to swim in the flooding water, out of the chamber, and into the pools and ponds. If the tadpoles hatch before the nest chamber is flooded, or in a year when the rains are not hard enough to overflow the pool or pond and flood the nest, the tadpoles in some species scramble onto the female's back, and she carries them out of the nest and to the water.