Scientists wielding thermal imaging tools are taking aim at rainforest depletion and its effect on vulnerable amphibian populations. It’s the pursuit of the Coburn Professor of Environmental Science at John Carroll University, Dr. James Watling, who leads a team of investigators in Columbia’s Magdalena River Valley. In the big picture, human activity has altered 43% of the earth’s terrestrial land, mostly, for agricultural uses.
“We’ve converted more (land) than the last time glaciers covered the earth,” he said during a presentation to staff of the Cleveland Museum of Natural History. “We’re losing a football field size to deforestation per minute.”
Dr. Watling brings the statistic closer to home by telling a story of his favorite cookie; it contains palm oil, a major contributor to rainforest conversion in Indonesia and South America. Palm oil is ubiquitous in snack foods; connection made to consumer behavior (Americans have increased their palm oil consumption ten fold in the last decade).
Thermal biology opens a window into the temperature difference between the cleared forest now pasture and the deep canopy where diurnal temperature fluctuates at about half the rate of change. The pasture, as a modified landscape, produces the most variation in temperature, Watling says. This is critical to ectothermic organisms like amphibians who have a very small “CT Max” or top end of their temperature range. He studies toads, tree frogs, lizards and geckos —species on the “red list” or most vulnerable to temperature change—because they perish within minutes of the temperature exceeding their CT Max.
Land use change in Columbia—which is the “most biodiverse place on the planet”— produced a 10 degree swing in temperature in the field, Watling observed. Climate change is forecast to produce an additional 1 to 2 degree Celsius increase. Combined, 5 to 30% of the Columbian rainforest could become “thermally unavailable.”
Asked if studies of “temperate” zones like Northeast Ohio would produce similar results, Watling commented that temperate species may be in a better position because tropical species have adapted to a narrower range of temperature. Though, certain human populations may be at greater risk.
“There’s an effort to look at climate change and the segment of the population that is aging and economically precarious. Heat waves are the worst natural disaster.”