Amphibian Pandemic Decimates Darwin's Frog Population

They are one of the world's most iconic amphibians, named after the famous evolutionary scientist Charles Darwin. 

 

Darwin's frogs (Scientific name: Rhinoderma darwinii) found in Chile and adjacent parts of Argentina are under 2 centimetres long and are recognisable by their distinctive, pointy noses. In fact, Darwin’s frog is the only amphibian in the world where the male carries tadpoles in its vocal sac.

 

They are considered vulnerable by the International Union for Conservation of Nature. 

 

Tantauco Park, in southern Chile, was home to the largest known populations of Darwin’s frog. In 2023, a team led by the Ranita de Darwin NGO and Andrés Bello University discovered that the chytrid fungus (Scientific name: Batrachochytrium dendrobatidis), which causes chytridiomycosis, had reached this natural paradise, previously free from the disease. In just one year, their numbers have plummeted by 90%.

 

[According to New Scientist on March 28, 2019, chytridiomycosis contributed to the decline of more than 500 species of frogs, toads and salamanders, or nearly 7 percent of all amphibian species, since the fungal disease first emerged in the 1980s].  

 

 

 

 

 

 

 

 

 

 

 

Faced with this devastating pandemic, a coalition of organizations quickly formed to launch an ambitious project aimed at rescuing and restoring this critical refuge for the species. One of the first emergency actions taken to address the imminent disappearance of Darwin’s frogs in Tantauco Park was the creation of a national and international network of captive breeding centers to safeguard the species while seeking a solution to the chytridiomycosis threat. 

 

And in October this year, conservationists organized a rescue mission which included capturing and flying 53 of the tiny frogs to the world's oldest scientific zoo in the UK.

Dr Andrés Valenzuela Sánchez (left) from London Zoo's Institute of Zoology who leads the project, said: "Moving 53 Chilean frogs to London was no small feat – it took meticulous planning and more than a few sleepless nights!" 

 

Ben Tapley, Curator of Amphibians and Reptiles at London Zoo added: “Transporting Darwin’s frogs to another continent was no easy task, especially as we were racing against time in a complex operation involving 51 people from 9 different institutions. Thanks to a dedicated global team and a strict biosecurity protocol, all the frogs survived the journey, which spanned 13,000 km by sea, land, and air”.

 

In addition to contributing to research on chytridiomycosis, offspring of Darwin’s frogs in the UK will be returned to Chile to support the reintroduction of the species in Tantauco Park. 

 

“We have built a dedicated facility for Darwin’s frogs at London Zoo, capable of replicating the light and humidity cycles of Chilean forests to ensure these tiny visitors feel secure and remain healthy during their stay” explained Sánchez. “I am convinced that the integration of research and conservation, both in captivity and in the wild, will allow Darwin’s frogs to repopulate Tantauco Park and thrive in their ancient native forests”.

 

Osvaldo Cabeza, a project member from Chile’s National Zoo, emphasized: “Captive breeding centers may be the last resort to safeguard amphibian populations facing imminent extinction due to chytridiomycosis”.