Chicago – A devastating fungus is sweeping the world, wiping out entire populations of amphibians at such a rate that biologists are helping pull together a massive “Noah’s Ark” to capture frogs, toads and salamanders and put them in safe places.
A variety of factors – global warming, pesticides and herbicides, acid rain and habitat destruction – already have combined to cause more than 120 amphibian species to vanish forever since 1980, in what one biologist has called “one of the largest extinction spasms for vertebrates in history.”
A third of the world’s nearly 6,000 amphibian species are threatened, their populations weak and susceptible to disease.
If they go, ecosystems will tilt out of balance and potential medical breakthroughs – such as potent painkillers or HIV inhibitors – could be lost.
It is hard to determine just how many species have been affected by the fungus because they cannot be assessed fast enough, but the organism has factored into most recent amphibian declines, said Bob Lacy, population geneticist at Illinois’ Brookfield Zoo.
There’s no no time for anything but a triage attempt to get some of the animals out of harm’s way, he said. “It is a race against time, and it’s a matter of months,” Lacy said.
Among zoologists, some have begun to face questions of which species should be saved.
“It’s terrible. I’ve never experienced anything like this,” said David Wake, a biology professor and curator of herpetology at the University of California at Berkeley, the first scientist to officially declare a pattern of global amphibian declines in 1989.
Some scientists point to the amphibians as bellwether animals for Earth’s health, more vulnerable to environmental changes. But chytridomycosis, caused by the chytrid fungus, is adding a confounding new peril that is pushing many species over the brink – even in areas mostly untouched by humans.
Chytridomicosis was first identified in 1998, and is not well understood. As it moves around the globe, it has caused massive amphibian die-offs in Australia and hit the population of boreal toads in the Rocky Mountains.
The disease is filtering down Central America – one of the most biologically diverse areas on the planet – at a rate of about 17 miles a year, faster than a frog can hop to the next pond.
