After spending two years in the Cloud Forests of Costa Rica, I became keenly interested in amphibians and their recent dramatic declines. According to the 2004 Global Amphibian Assessment, 43 percent of all amphibian species are experiencing some form of population decrease, 32.5 percent are threatened, and 122 species have possibly gone extinct since 1980. Recent research has centered on a chytrid fungus, Batrachochytrium dendrobatidis (Bd) as one of the major contributors to these declines. This fungus has been found worldwide, and it has been hypothesized that climate change, host behavior, and life histories may play important roles in its virulence. Here in Arizona, I use populations of infected chorus (Pseudacris maculata) and leopard (Rana spp.) frogs to investigate the dynamics of Bd in wild amphibian populations. This host-pathogen system represents a rare opportunity to study how environment, host behavior, and pathogen virulence interact to create population declines and extinctions. What conditions allow for Bd to persist in a host population? Why does Bd drive certain host populations to extinction while others persist? These questions are key to understanding the spread of Bd and its dynamics in host populations. Along with making significant contributions to amphibian conservation, knowledge of Bd dynamics will also add to our understanding of multi-host pathogens in wild animal populations and help to devise strategies to prevent pathogen spread and host declines.
<< back to main people page