That's when ecologist Martha Crump, then at the University of Florida, reported that the famous golden toad of Monteverde, Costa Rica, had dropped from sight. Ever since, scientists have warned that human-caused environmental problems are hurting amphibians around the world, although the exact causes of some declines remain unknown. We need to be able to answer these questions to be able to successfully manage for amphibians. Still, there are plenty of obvious reasons for the creatures' problems. Even the arroyo toad's relative paradise on San Mateo Creek is far from a perfect home.
Roads run along both sides of the waterway, and traveling toads get squashed by passing cars.
Introduced bullfrogs, opossums and house cats prey on incautious toads. Exotic pest plants threaten to change the creek's open bed. In short, these toads face many of the dangers scientists agree contribute to amphibians' problems worldwide. These include habitat loss, habitat fragmentation, habitat degradation and pollution. Each of those environmental ills affects its amphibian victims in specific ways.