The Real Reason Why the Frog Population "Exploded" Recently

The change that made a difference.

Good environmental news is not in huge supply these days, but scientists in Switzerland report that the population of endangered tree frogs and other amphibians has "exploded" after they made one key change. Read on to find out what it was, and why researchers hope it will go global. 

The Change That Made a Difference


BBC News reports that in Aargau, Switzerland, after environmentalists dug hundreds of new ponds, the numbers of endangered frogs, toads, and newts rose significantly. The European tree frog population "exploded," scientists said. They hope the method can be used worldwide to boost amphibian populations, which are on the decline because of humans infringing on their habitats, urban development, disease, and predators.

How It Came About


In 1999, Aargau launched a conservation program to address the declining numbers of amphibians. The European tree frog seemed to be in terminal decline. Over 20 years, government agencies, nonprofits, and hundreds of volunteers built 422 ponds in five areas of the state, creating new spaces for the species to live and reproduce. Two decades later, 52% of the endangered species had larger populations, and 32% were stabilized.

"Species Will Come," Says Study Author


Dr. Helen Moor, lead author of the study, told BBC News she was excited to see "such a clear increase" in endangered populations considering how simple the solution was. "Species will come, they will settle and start using the space if you offer it to them," she said.

Tree Frog a Positive Case Study


In particular, researchers targeted the European tree frog, an unusually mobile species that jumps from shrubs to trees and can travel for several miles. It thrives in a certain habitat—shallow ponds created by rivers or flood plains. But those areas had largely disappeared in Switzerland, decimating the species' numbers. But the pond construction had a noticeable effect: In one area, the tree frog population quadrupled. In 1999, it could only be found in 16 sites, but by 2019 it was spotted in 77.

"It Pays to Do Something"


Like many countries, Switzerland has seen rural areas increasingly developed and intensely farmed. The country has a high population density, and development, including the formation of large road and rail networks, has encroached on natural habitats. "Habitat loss is one of the main problems, and just by addressing that we could see the difference it made, and begin the recovery of these species," Moor told the BBC. "The key message is that it pays to do something, even if it feels overwhelming."

Michael Martin
Michael Martin is a New York City-based writer and editor. Read more
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