In a first for researchers, the endangered African Goliath frog has been observed ‘nest-building’ in the wild.
Described by the Journal of Natural History, adult Goliath frogs were found moving rocks weighing up to 2kg to build ponds for their young, which they then guarded. Goliath frogs themselves weigh up to 3.3kg, with bodies reaching over 34cm, not including their legs. These new findings could explain why the frogs have grown to be so big in size.
“Goliath frogs are not only huge, but our discovery shows they seem to be attentive parents as well,” says author Marvin Schäfer from the Berlin Natural History Museum. “The little ponds they make at the edges of fast-flowing rivers provide their eggs and tadpoles with a safe haven from sometimes torrential waters, as well as from the many predators living there. We think that the heavy work they put into excavation and moving rocks may explain why gigantism evolved in these frogs in the first place.”
Goliath frogs are found only in Cameroon and Equatorial Guinea and little is known about their biology. Numbers of the endangered species have declined by more than 50 per cent in just 10 years, due to overhunting and deforestation.
Scientists used time-lapse video to recorded the new Goliath frog behaviour in detail, which suggested that males carried out the construction of the ‘nests’ while females are the guards.
Dr Mark-Oliver Rödel, project leader and president of Frogs & Friends, says: “The fact that we’ve only just discovered these behaviours shows how little we know about even some of the most spectacular creatures on our planet. We hope that our findings, combined with further ongoing research, will improve our understanding of the needs of the Goliath frog so we can help support its continued survival.”