A report published today in the October 4 issue of The Public Library of Science, includes findings that may give important new clues concerning this pathogenic organism's behavior in the wild, and a step towards understanding how it spreads.
The paper, written by Arizona State University biologist Richard Retallick, Hamish Ian McCallum from the University of Queensland, and Richard Speare from James Cook University, finds evidence for the persistence of the fungus in surviving populations of Taudactylus eungellensis, a species that had suffered a massive decline.
The species largely disappeared from rainforest streams in the mid-1980's, but surviving remnant populations sampled in the mid-1990's show the continued presence of the fungus in 15% to 18% of the sampled frogs. Later investigation showed that infected frogs had similar survival to uninfected frogs.
"This shows that frog populations can persist with an endemic infection of the chytrid fungus," said Retallick. "The presumption until now has been that when a population is hit by this pathogen it is wiped out. It doesn't appear to be that simple.
"In Central America and Eastern Australia, the same pattern has occurred the frog populations have been healthy and all of a sudden there is a crash and some species are wiped out entirely. In Eastern Australia several species crashed to extinction, among them the Northern Gastric Brooding Frog, which lived in the same environment as T. eungellensis." Retallick said.