More than 20 species of frogs and toads in Costa Rica may be on the path to extinction traveled by the golden toad, and national biologists are working to prevent their disappearance, explained Federico Bolaños, a herpetologist at the University of Costa Rica (UCR) in San Pedro, east of San José.

Scientists are concerned about the drastic decrease in amphibian populations across the Central Ame rica since the 1990s, but to date they have only a few hypotheses to explain the cause of those dwindling numbers.

At least 2,000 of the almost 6,000 species of toads, frogs, salamanders and caecilians worldwide are at risk of extinction. Costa Rican scientists are working to design a national strategy to guarantee the survival of many of these species over the next 25 years, Bolaños said.

Research to date points to two main causes of this alarming situation: global warming and a common fungus known as chytrid. Apparently, climate change in recent years has altered living conditions for amphibians and caused new diseases to appear and existing ones, such as the chytrid, to modify, Bolaños said. “The number of species under threat could climb to 3,000, or half of the world’s amphibian species”.

Costa Rica is home to 181 species of amphibians. The small, shiny golden toad that once thrived here has not been seen anywhere in the world since 1989 and is classified as extinct by the Switzerland-based International Union for Conservation of Nature and National Resources.

Apparently traveling down the same path are 23 other multi-colored and exotic species like the Harlequin frog, some venomous frogs and most of the toad family, with six of 14 species gravely endangered, said herpetologist Gerardo Chaves.

-ACAN-EFE