USF study shows evidence of frogs getting sick from climate change listen11/15/12 Olivia Kabat
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A study conducted by the University of South Florida shows evidence that frogs are getting sick more often because of climate change. The research found that fluctuations in temperature decrease frogs’ resistance to a deadly pathogen that is linked to worldwide amphibian declines.
Jason Rohr, co-author of the study and associate professor of Integrative Biology at USF, says the study provides an understanding of how climate change plays a role in the global well-being of amphibians.
“We hypothesized that these temperature shifts would benefit the pathogen more than the host. We found some field evidence linking amphibian declines associated with this chytrid fungus to temperature shifts. We then conducted some experiments in the laboratory and showed that frogs exposed to a temperature shift had higher loads and were more likely to die of those infections than frogs kept at a constant temperature.”
Frog declines can be linked to global warming. Rohr says warmer years had larger drops in temperature and more frog extinctions than cooler years.
“The area where they were finding lots of dead frogs was in Panama. So there’s a well documented spread of the pathogen through Panama. Now Panama is a very narrow country and there were researchers that were able to actually get in front of this spreading pathogen and they documented that the frogs were all fine before the pathogen arrived and then they started dying once the pathogen got there. There’s other evidence, especially evidence in the Sierra Nevada’s of California where they’re able to show the pathogen is spreading and the frogs are fine before the pathogen gets there and then they start dying when the pathogen arrives.”
According to Rohr this is one of very few studies that have considered how inconsistencies in temperature affect disease risk in amphibians.
“I am unaware of any frog species that’s been found that is completely resistant to this pathogen; they all seem to be capable of getting infected. Climatic shifts could indeed facilitate fungal population growth rates so it can cause extinction. We are actually looking into some potential solutions to amphibian declines associated with the chytrid fungus in my lab right now. But they're more focused on either eliminating the pathogen or increasing the resistance or tolerance of the host to the infections.”
Rohr says the frogs continue to suffer from the deadly parasite but research will continue to try to find a useful solution.