Enclosure status
Temporarily closed
Population in the wild
IUCN status
Critically Endangered
Scientific name
Leptodactylus fallax
Dominica and Montserrat

World's biggest frog

Mountain chickens are one of the biggest frogs on the planet, weighing in over 40 times the size of European common frogs which can be regularly be seen in gardens. There are now just around 21 mountain chicken frogs remaining in the wild, as an amphibian fungus epidemic wiped out over 99% of their population when it arrived in 2002. 

At the Zoo we're breeding mountain chickens to help recover their populations, while carrying out scientific research to discover the solution to the deadly fungus that nearly wiped them out forever. 

 Frog parental care

These frogs care for their young, as pairs produce a foam nest to lay their eggs into. The tadpoles are then fed unfertilised eggs by the female to feed on during their development, producing between 10,000-25,000 eggs. 

Mountain chicken conservation

Our conservationists along with other conservation zoos helped save the species from extinction in 2009, by airlifting them to the safety of a dedicated breeding facility. Today we're continuing to work to restore mountain chicken frogs, through leading scientific research and breeding them at a Secret Life of Reptiles and Amphibians.

Our work at ZSL

Mountain chicken frog in a persons hand
ZSL conservation in action

Mountain chicken conservation

We are a part of the collaborative Mountain Chicken Recovery Programme, which is leading cutting-edge mountain chicken conservation.

Secret Life of Reptiles and Amphibians

  • Mallorcan midiwfe toad sitting on a rock
    Alytes muletensis

    Mallorcan midwife toad

    They were first described from fossils in 1977 and presumed to be extinct. The first living toads were found in 1979. They are threatened by invasive species that were introduced by the Romans. 

  • Chinese giant salamander being held during a health check at London Zoo
    Andrias davidianus

    Chinese giant salamander

    Chinese giant salamanders are the world's biggest amphibian, at full size they are around the size of a fully grown man at 1.8m in length.  

  • Mangshan pit viper with forked tongue out
    Protobothrops mangshanensis

    Mangshan pit viper

    One of the rarest of all snakes and were only identified by the scientific world in 1990.

  • Philippine Crocodile at London Zoo
    Crocodylus mindorensis

    Philippine crocodile

    There are one only around 120 left in the wild, but we are working to recover Philippine crocodiles at the Zoo and in the field.

  • Secret Life of Reptiles and Amphibians