The Environment in Focus with Tom Pelton | Yesterday

A new study concludes that populations of frogs and other amphibians are declining across the U.S. at a rate of almost 4 percent a year, which is faster than previous estimates. One of the authors, David Miller, an ecologist at Penn State University, said the global spread of two mysterious pathogens--the ranavirus and chytrid fungus--are likely partly to blame for the deaths.