The disease is called chytridiomycosis - chytrid, for short. It's a type of fungus which eats away at the skin of frogs, toads and salamanders (amphibians that live their lives partly on land and partly in water). Their skins are porous so they take in some of the water they need through their skins rather than by drinking it. Diseased skins mean they can't take in the water so they die, sometimes of heart attacks. The research was carried out by Dr Ben Scheele and Dr Claire Foster of the ANU's Fenner School of Environment and Society. Lead researcher, Dr Scheele, said that the disease started in East Asia and then spread around the world as diseased animals got carried in cargos, perhaps of fruit. The global trade in wildlife didn't help. The ANU research is the first to identify an imported fungus as a devastating invader. Threatened. Southern corroboree frog (Pseudophryne corroboree). Credit:Corey Doughty.

There have been other destructions of animal populations when animals have crossed boundaries and defenceless native species suddenly have an unbeatable predator - cats, rats and red foxes brought from Europe have both devastated native species in Australia (red foxes were imported in the 1850s by Europeans who missed their traditional hunting of the fox). Dr Scheele said that the unprecedented number of declines of species caused by chytrid placed it "among the most damaging of invasive species worldwide – similar to rats and cats in terms of the number of species each of them endangers. “Highly virulent wildlife diseases, including chytridiomycosis, are contributing to the Earth’s sixth mass extinction,” Dr Scheele said. “We’ve lost some really amazing species.” “We’ve got to do everything possible to stop future pandemics, by having better control over wildlife trade around the world.”

Threatened. Mossy red-eyed frog (Duellmanohyla soralia). Credit:Jonathan E. Kolby, Honduras Amphibian Rescue & Conservation Center. One of the problems is that some species are resistant to the fungus - they get it but aren't harmed by it - so they continue to keep it in the eco-system. Both Dr Scheele and Dr Foster said that the best way of slowing the spread was to be extra tough at borders to prevent the import of infected animals. There are new strains of the fungus - like flu, it morphs into different types - so there needed to be a lot of vigilance to detect new strains and stop them getting to Australia. Dr Foster said the ANU-led study involved close collaboration with researchers in Belgium and 38 different amphibian and wildlife disease experts from around the world.