Species Fact Profile: African Bullfrog (Pyxicephalus adspersus

African Bullfrog

Pyxicephalus adspersus (Tschudi, 1838)

Range: Sub-Saharan Africa
Habitat: Grasslands, Wetlands, Woodland
Diet: Tadpoles eat vegetation and small invertebrates.  Adults eat invertebrates and small vertebrates, such as rodents, snakes, and small birds
Social Grouping: Solitary outside of mating congregations
Reproduction: Breed after heavy rains, gathering in bodies of water.  Males congregate and call for females, who usually mate with the biggest males.  Females lay 3000-4000 eggs, which are guarded by the males, even after hatching.  Metamorphosis takes place three weeks after hatching
Lifespan: 15 Years (up to 35 years)
Conservation Status: IUCN Least Concern

• Males may grow up to 23 centimeters in length and weigh up to 2 kilograms (usually about 1.5 kilograms).  Females are about half that size - unusual, as in most species of frogs, females grow larger than males
• The body is olive green (sometimes appearing brown, grey, or even blue) with ridges running down the length of the body.  The forelimbs turn bright yellow in breeding males.  Juveniles have a pale stripe running down the length of the spine, fading with age
• Both adults and tadpoles may practice cannibalism; larger males may eat smaller males during breeding congregations, and newly-hatched tadpoles may eat their siblings.  Guarding fathers may eat some of their tadpoles
• Males that are left to guard their tadpoles may find themselves in pools that are drying out before the tadpoles are ready to leave the water.  They may dig canals from their pools to larger bodies of water to save the young from drying out
• Found in a wide variety of climates, some of which only allow the frog to be active for a portion of the year.  In dry conditions, adults will bury themselves, using tubercles on the back legs.  Then, they may shed several layers of skin to form a cocoon, helping them preserve moisture, while bodily functions slow down to help conserve energy.  Frogs may stay underground for up to a year
• To hunt, the frog will often lie underground with only the nose exposed, waiting for small animals to approach