Background
The authors write that "considerable controversy exists concerning whether or not climate changes (particularly global warming) are causing outbreaks of a lethal amphibian pathogen, the chytrid fungus Batrachochytrium dendrobatidis (Longcore, Pessier & Nichols 1999)," although the vast bulk of evidence clearly suggests that global warming is not the culprit many have tried to make it out to be. See, for example, many of the items listed under the general heading of Frogs and Toads in our Subject Index.

What was done
In a further exploration of the issue, Bustamante et al. exposed groups of Panamanian golden frogs (Atelopus zeteki Dunn, 1993) -- a critically endangered amphibian thought to be nearly extinct in Panama -- to varying dosages of zoospores of Batrachochytrium dendrobatidis or Bd, as well as to different temperatures and hydric environments, in order to determine if the frogs were susceptible to the pathogen and, if so, how environmental factors might affect the frogs' survival.

What was learned
The three researchers report that (1) "frogs exposed to a dosage of 100 Bd zoospores survived significantly longer than those that had been exposed to 10⁴ or 10⁶ zoospores," that (2) "exposed frogs housed at 23°C survived significantly longer than those that were housed at 17°C," and that (3) "exposed frogs held in dry conditions survived significantly longer than those in wet conditions."

What it means
Since their study was conducted in a laboratory, Bustamante et al. acknowledge that their results "do not directly test hypotheses about the relation between climate change and the decline of the frogs in the field," but they note that their data nevertheless "do not support the contention that rising global temperatures are necessary to cause the death of amphibians infected with this pathogen, because the pathogen was equally lethal at 17 as at 23°C, and frogs at the warmer temperature lived significantly longer than those at the cooler one." Hence, their work provides yet another substantial nail to drive in the coffin of the recently-expired climate-linked epidemic hypothesis of Bosch et al. (2007) and Pounds et al. (2006), of which latter paper Bustamante had been the second of fourteen coauthors. (You got to love a person who rejects her own hypothesis when the data stack up against it.)

References
Bosch, J., Carrascal, L.M., Duran, L., Walker, S. and Fisher, M.C. 2007. Climate change and outbreaks of amphibian chytridiomycosis in a montane area of Central Spain: Is there a link? Proceedings of the Royal Society B 274: 253-260.

Pounds, J.A., Bustamante, M.R., Coloma, L.A., Consuegra, J.A., Fogden, M.P.L., Foster, P.N., La Marca, E., Masters, K.L., Merino-Viteri, A., Puschendorf, R., Ron, S.R., Sanchez-Azofeifa, G.A., Still, C.J. and Young, B.E. 2006. Widespread amphibian extinctions from epidemic disease driven by global warming. Nature 439: 161-167.