USF: Climate Change Can Be Deadly for Frog Populations

A new study by the has identified climate change as a culprit in dwindling frog populations.

“Laboratory experiments … and field data on disease-associated frog declines in Latin America support the framework and provide evidence that unpredictable temperature fluctuations … decrease frog resistance to the pathogenic chytrid fungus,” states the study published Aug. 12 in Nature Climate Change.

Chytrid fungus is considered a top threat to amphibians around the globe, according to USF.

Using 80 incubators, scientists housed frogs at either 15 degrees or 25 degrees Celsius. Half of the populations at each temperature were then switched to the other temperature, according to USF. After introducing the fungus, it was found that the frogs that were switched had higher rates of fungal growth as well as higher rates of “fungal-induced mortality” than those that were kept at the same temperature all along.

The reason?

“We suspect the drop in temperature affects (the frogs’) immunity,” Jason Rohr, a co-author of the study and associate professor of integrative biology at USF, told Patch. “In addition, we have hypothesized that drops in temperature might benefit pathogens … because pathogens are always smaller and therefore have faster metabolisms.”

Rohr said the study shows that temperature variability — and not just mean temperature — is likely having an impact on pathogen growth caused by climate change.

“This might suggest that climate change is an under-appreciated link between global disease emergence and biodiversity losses,” he added.

What do you think of the study's findings? Let us know in the comments section.

On the web:

• USF's Department of Integrative Biology
• Full text of the study: "Disease and thermal acclimation in a more variable and unpredictable climate."