The Giant Bullfrog (Pyxicephalus adspersus) is the largest southern African frog. This species breeds in the shallows of temporary rain-filled depressions in grassland and savanna which it defends aggressively from intruders, even lunging at lions. It remains buried most of the year encased in a waterproof cocoon consisting of layers of shed skin. In Mozambique, this species breeds in rice paddies. The male's call is like the barking of a small dog and, by moonlight, its white vocal sacs are visible when inflated.
Populations of the Near-Threatened giant bullfrog have been poorly monitored due to the unpredictable appearance of this species aboveground. Animals move overland, forage at night, around full moon, after heavy rainfall, when cooler, and less windy conditions prevail. More animals are found at water, or on land during the day, and population spawn is more likely, earlier in summer, following heavier rainfall. Spawning occurs most frequently, in descending order, during December, January, and November, and is triggered by rain in 24 hours.
- Frogs and Frogging in Southern Africa. Vincent Carruthers
- The Book of Frogs: A Life-Size Guide to Six Hundred Species. Tim Halliday
- Spawning and non-breeding activity of adult giant bullfrogs (Pyxicephalus adspersus). African Journal of Herpetology 60(1):13-29 · April 2011