​In a canton in Switzerland, a long-term conservation program has resulted in the rescue of some species of frogs and the proliferation of others. Frogs and other amphibians are in serious decline worldwide, especially as the ponds where they lived no longer exist and are often replaced by construction.

In five regions of the Swiss canton of Aargau, 422 ponds were set up so that frogs had a place to live and breed.

The program lasted 20 years, and it was concluded that the number of half of the endangered species increased, and 32% stabilized. In some areas, the European toad could be found in 16 ponds two decades ago, but today there are 77.

The study is published in the journal PNAS under the title Bending the curve: Simple but large-scale conservation action leads to landscape-scale amphibian recovery.

The authors of the study say that the results are very good, considering the simplicity of the solution: setting multiple rates. The good thing is that people have stuck with it and followed the program for two decades.

Frogs have declined across Europe as they lose their habitat in a rapidly urbanizing world, with more and more wild areas disappearing, replaced by housing developments, shops or roads.

Sources: BBC, PNAS