Recently, we read an intriguing article in the Deccan Herald (India), about how a team of scientists in India are literally listening to frogs to understand the effect of climate change on amphibian populations.

Three scientists, K.S. Seshadri with T. Ganesh, and S. Devy, were doing research 100 feet above the ground in the canopy of the evergreen forest in the Kalakad Mundanthurai Tiger Reserve. While getting drenched with rain, they heard a cacophony of frog songs. Intrigued by the songs that the rains triggered, they initiated a program to study frog calls to both monitor populations and to study the affect of climate change on frogs.

Volunteer examines the monkey-proof enclosure for equipment to record frog calls. Photo credit: K. S. Seshadri

Amphibian Meterologists

Frogs can tell us a lot about the weather. Their skin is extremely thin and sensitive; they respond to even small changes in atmospheric moisture and temperature. The scientists reasoned that an analysis of sound recordings, combined with readings from climate data loggers, could help improve our understanding of the impact of climate change.

Climate change seems to underlie many of the threats facing frogs worldwide. By monitoring the frog calls, an activity calendar for each of the indicator species can be made. This long-term monitoring will be invaluable in understanding the greater impact of climate change and also might help to save frog species.

Work station studying frog calls, high up in the forest canopy. Photo credit K. S. Seshadri

As the Deccan Herald put it: “Will the croak alarm finally wake us from our ignorant slumber? The answer lies in the future.”

For more information:

“What Frogs Tell Us About the Planet,” Decclan Herald, India

“Frog song and climate science,” Ashoka Trust for Research in Ecology and the Environment

photo courtesy National Park Service. Department of the Interior

According to the Center, the population of Sierra Yellow legged frogs has decreased by 75% in recent decades. Reading about these frogs, we were struck by how they are a symbol of the challenges that frogs face worldwide. But they aren’t facing one challenge—they seem to be facing almost all of them:

Introduction of nonnative species: Stocking of nonnative trout in high-elevation Sierra lakes has been the main cause of the species’ decline. The trout eat tadpoles and juvenile frogs and alter the food web of the aquatic ecosystems on which the native frogs depend. The Department is recommending no trout stocking in the state without a fish management plan, and no further stocking of trout in areas that would conflict with protecting yellow-legged frogs.

Pesticides: Recent research has linked pesticides that drift from agricultural areas in the Central Valley to declines of native amphibians in the Sierra Nevada. Pesticides and other pollutants can directly kill frogs and also act as environmental stressors that render amphibians more susceptible to diseases, including a chytrid fungus that has recently ravaged many yellow-legged frog populations.

Loss and degradation of habitat: Grazing, logging, water diversions, off-road vehicles and recreational activity are allowed in frog habitat.

Climate change: Climate change has brought warmer temperatures, decreases in runoff, shifts in winter precipitation in the Sierra from snow to rain, and habitat changes that are rendering frog populations more vulnerable to drought-related extinction events.

A recent settlement agreement with the Center for Biological Diversity, which will also speed protection decisions for 756 other species, requires the U.S. Fish and Wildlife Service in 2013 to make a decision about whether to add the Sierra frog to the federal endangered list.

See the Center for Biological Diversity for more information about these frogs and about the other endangered species they are working to protect.