New evidence details spread of amphibian-killing disease from Mexico through Central America

Museum specimens help tell the story

Using museum specimens from Mexico, Guatemala and Costa Rica, a team of researchers from San Francisco State University and University of California at Berkeley has documented evidence of a Batrachochytrium dendrobatidis (Bd) epidemic wave that wiped out native amphibians, according to research to be published on May 3 by the Proceedings of the National Academy of Sciences. (PNAS).

More than 40 percent of all amphibian species are currently in decline, with many species having already disappeared, even in protected areas. The suspected culprit has been the emergence of a fungal pathogen, Bd, which coincided with the decline of the amphibian community

Using samples collected before, during and after the decline, Cheng, et al., documented the spread of the infection from southern Mexico southward in the early 1970s to western Guatemala in the 1980s and 1990s and to Costa Rica by 1987.

The technique used may help determine whether the disease is the cause for the collapse of the amphibian populations in Australia, South America and North America.

Nan Broadbent
San Francisco State University