It started off as an enigma. Biologists at field sites around the world reported that frogs had simply disappeared. Costa Rica, 1987: the golden toad, missing. Australia, 1979: the gastric brooding frog, gone. In Ecuador, Arthur’s stubfoot toad was last seen in 1988. By 1990, cases of unexplained frog declines were piling up. These were not isolated incidents; it was a global pattern – one that we now know was due to chytridiomycosis, a fungal disease that was infecting and killing a huge range of frogs, toads and salamanders.
Our research, published in Science, reveals the global number of amphibian species affected. At least 501 species have declined due to chytrid, and 90 of them are confirmed or believed extinct.