Produced by Katie Garrett
Chytrid fungus (Batrachochytrium dendrobatidis [Bd]) and the disease it causes has wiped out countless populations of frogs throughout the world. While its exact origins aren’t known, recent estimates suggest that chytrid disease has contributed to the decline of more than 500 amphibian species and led to as many as 90 extinctions globally. This devastation has wreaked havoc on entire ecosystems and left scientists and conservationists baffled and uncertain as the species and environments they’ve worked so hard to understand and protect have simply winked out.
While the disease is by no means under control, especially in Central and South America, some frogs appear to be at least somewhat resistant to it. And now researchers in Brazil and their collaborators at the California Academy of Sciences are studying some of these populations and conducting an ambitious field experiment designed to better understand factors that influence how chytrid fungus spreads and the severity of disease it causes.
Their research focus in this, the largest tract of Atlantic Forest in South America, less than 60 kilometers from Brazil’s largest city, is one of the region’s tiniest amphibian species and one of its most abundant: the pumpkin toadlet (Brachycephalus pitanga). The hope is that what they learn from studying this diminutive species will ultimately help them and other scientists and conservationists around the world predict and possibly prevent major chytrid outbreaks in the future.

Serra do Mar State Park, Brazil
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