Other sites are also yielding good news. Some amphibians aren't affected by the fungus or can carry it without being hobbled. Certain Costa Rican tree frogs have skin pigments that allow them to bask in the sun without drying out, killing the fungus with heat. Most encouraging, Reid Harris of James Madison University and colleagues have found an innate defense in salamanders and some frogs: symbiotic skin bacteria that inhibit chytrid infection. (Some naturally occurring skin proteins show similar fungus-fighting properties.) "If we can augment the good bacteria to help lower transmission, there may be time for the animals to ramp up their own immunity," Harris says. "And we wouldn't be putting anything into the environment that isn't already there. Perhaps we can stop the epidemic outbreaks of chytrid."

Upcoming Amphibian Ark projects may help researchers test these measures. In Panama, chytrid has only recently jumped the canal and begun a march eastward toward the still pristine Darién Province, where at least 121 amphibian species are known. One rescue facil­ity is already up and running there; U.S. and Panamanian partners are now planning another—in part for research into how to boost enough healthful skin microbes in wild populations to stop the fungus cold. If the strategy works, the golden frog, for one, may be returned in healthy numbers to Panama's forests. Meanwhile, in frog-rich Ecuador, Coloma and Ron have petitioned the government for an environmental audit of the Limón road project. Construction has ceased for now, and some habitat restoration may be done. Though perhaps too late to save the choked stream's animals, media attention there could help future land preservation efforts.

Why care about frogs? "I could give you a thousand reasons," says Coloma. Because their skin acts not only as a protective barrier but also as a lung and a kidney, they can provide an early warning of pollutants. Their insect prey carries human pathogens, so frogs are an ally against disease. They serve as food for snakes, birds, even humans, playing a key role in both freshwater and terrestrial ecosystems. "There are places where the biomass of amphibians was once higher than all other vertebrates combined," says David Wake. "How can you take that out of the ecosystem without changing it in a major way? There will be ecological consequences that we haven't yet grasped."

"The story is much bigger than frogs," says Vredenburg. "It's about emerging disease and about predicting, coping with, and fighting things we don't fully understand. It's about all of us. Everyone should care."