African Treefrogs: Hyperoliidae

Physical characteristics: The bubbling kassina, also known as the Senegal running frog, is a light greenish gray to tan frog with wide, dark, often brown or black striping or spots on its head and back and dark blotches on its front and rear legs. In many, the markings on the back and head include one long stripe beginning between the eyes and continuing almost to the rump, one broken stripe on each side, a stripe from the tip of the snout to at least the shoulder, and another blotch or several spots low on each side. On its head, the large eyes may look light olive gray to tan or gold, and each has a vertical pupil. Most other African treefrogs have horizontal pupils. Its front legs are not overly long, and its hind legs are only a bit lengthier than the With its small hind legs, the bubbling kassina does not hop but instead walks or runs, which is why it is sometimes called the Senegal running frog or simply a running frog. (© K. H. Switak/Photo Researchers, Inc.) front pair. Both have a pattern of dark bars on lower legs and onto the feet. The front toes have no webs between them; the rear toes have a little webbing. Its belly is white.

Males and females are about the same size. They each reach about 1 to 1.9 inches (2.5 to 4.9 centimeters) long from the tip of the snout to the end of the rump. In some areas, the size of the frogs is on the small side, but in others, most grow closer to the maximum size of 1.9 inches (4.9 centimeters) in length.

Geographic range: It lives over the southern two-thirds of Africa from South Africa north to parts of Sudan, Mali, Ethiopia, Senegal, Niger, and Chad.

Habitat: These frogs are terrestrial (te-REH-stree-uhl), which means they live along the ground. For much of the year, they are usually found in grassy areas, although some make their homes in more shrubby areas, in pastures, or in country gardens. They mate in shallow spots in ponds or swamps, usually those places with a good deal of plants living in the water.

Diet: These frogs probably eat arthropods.

Behavior and reproduction: With its small hind legs, the bubbling kassina does not hop but instead walks or runs, which is why it is sometimes called the Senegal running frog or simply a running frog. When it sits still, this small striped frog almost disappears against the blades of grass in the grasslands where it lives. It becomes much more noticeable when the rainy season arrives and the males begin calling. The male's call is a high "poink" sound that is rather similar to a bubble bursting or a drop of water landing in a small, metal tub. The male only makes one "poink" sound at a time, usually waiting a while between the sounds. Males call at night while sitting in grass, often on the shore of a pond or swamp and under an overhang, such as a low, dirt cliff. They may also call from a spot in shallow water and surrounded by grass. Females join the males to mate with them in the water. A female lays her eggs one at a time on underwater plants. Each egg has a gel coating, and groups of them may stick together in a clump on the plants. The eggs hatch into tadpoles, which have wide fins, and pointy tails.

Bubbling kassinas and people: Many people in the grasslands of Africa enjoy the call of the bubbling kassina. Yet they very rarely actually see one. As a person nears a calling frog to find it, the frog stops calling and sits still. When the frog is not moving, its color and pattern help it to blend into the grass and make it very difficult to spot.

Conservation status: The IUCN lists this species in the category of "least concern," which means that it is under no known threat of extinction and the animal does not qualify for any of the Threatened categories. The bubbling kassina is a common species that lives over a large part of Africa, including numerous parks and other protected areas. ∎