Amphibians are disappearing around the globe. They are under pressure because of habitat loss, climate change and the deadly chytrid fungus. Scientists are trying to stop “the new extinction”
By Emanuele Biggi and Francesco Tomasinelli
Amphibians landed the first time about 400 million years ago and found a rich and not so demanding habitat to live in, so they rapidly reached big body sizes and the top of the food chain, remaining enthroned on it for about 100 millions years. At the end of the Permian new land invaders – the crocodiles “prototypes” – began to compete with Amphibians both for food and place to live.
This phenomenon led to the miniaturisation of Amphibians and their spreading to colder regions, where crocodiles couldn’t survive for their impossibility to hibernate.
Since that first radiation these animals changed their lives thousand times, powering up their skin with venoms and antimicrobial substances and adapting to nearly every habitat in the globe except the poles.
Now they are probably facing their worst period ever.
Hundred of species are close to extinction or they already disappeared mostly because of habitat loss and new aggressive diseases. The human species is probably the main cause of their drop: climate changes, habitat loss and the spreading of the chytrid fungus are devastating many populations. This last disease, that causes skin damage and suffocation to the infected animal, is even a bigger mystery: it’s widespread all over the world but it has the same genetic code everywhere.
This probably means that it had a very fast propagation in a few years and humans are probably the main vector.
The 70% of Atelopus toads is already extinct or in the brink of extinction and many species like Telmatobius frogs and other Central and South American species are in the same danger.
Hylomantis lemur, the Lemur Leaf frog is disappearing from most sites and all the higher altitude populations are already extinct.
The Peruvian Amazon is one of the hot spot of world biodiversity, both in cloud forests and into the flat, lush lowlands. Over there, into the Manu National Park and into the Madre de Dios area, we had the opportunity to document the effort of different researchers, like Alessandro Catenazzi‘s team, to save Amphibian populations. They compare data from the past with present data collected in the field and try to understand which is the impact of the chytrid fungus. Despite some bad news, new species are discovered almost each year and the Amphibian population remains in good health in some parts of their region, with the disease limited to some montane areas.
Many thanks to Alessandro Catenazzi and his team, Rudolf Von May, prof. Maureen A. Donnelly, Nigel and Renata Pitman and all the crew of the CICRA Los Amigos biological station in the Peruvian Amazon.