Nobody has really tried. The decline of the California red-legged frog is part of a larger mystery. Scientists report a global loss of amphibians including salamanders, newts and toads. So far, there is no conclusive explanation. Loss or change of habitat is part of the problem, DiDonato says.
Biologist say something else is happening, too.
Amphibians might be harmed by ultraviolet radiation from a thinning of the Earth's protective ozone layer, some say. Others suggest acid rain might be responsible. Research in Sequoia National Park indicates acid fallout from air pollution is stored in winter snowpack, then flushes into the ponds and lakes during the spring breeding season, DiDonato says. Jennings isn't so sure. If acid rain was affecting amphibians, it also would affect fish, Jennings says.