Grosselet Olivier and his wife Vauche Melina. Picture by Santanu Ghosh

Silchar, June 11: The once ubiquitous frog is struggling to survive in the marshes of south Assam’s Barak Valley, causing concern among conservationists not just here but also in faraway France.

Alarmed by the findings of the Environmental Society of South Assam, the France-based International School for Studies on Natural Science recently sent two experts to Cachar district for a “broad-based study” on the frog species found in the valley.

The duo, 35-year-old zoologist Grosselet Olivier and his 26-year-old conservationist wife Vauche Melina, spent a few days scouring the marshes for the 52 identified frog species that inhabit the area. They discovered that the exotic Indian bullfrog (rana togrina) had been affected the most by ecological changes.

“We travelled to almost all the frog habitats in the Barak Valley and recorded the distinctive croaks of each species. This will help us identify each species and arrive at a conclusion on the population,” Olivier, a graduate from the National Museum in Paris, said. The French couple conducted their research with a tape-recorder equipped with a highly sensitive microphone and a spectrogram, which is a gadget for analysing sounds.

Olivier, whose had previously studied frogs in Mexico and China, said frog species were under threat mainly from pesticides used in cultivation and unplanned urbanisation.

His wife, who is also a sociologist, added, “Frogs are essential to maintain the ecological balance as they help maintain nature’s food chain. They eat insects, which otherwise destroy crops.”

The duo will next visit Cachar after the monsoon sets in and the mating season of frogs starts. They hope to submit their recommendations immediately after completing the second round of research. “One of our suggestions will be to turn a portion of low-lying farmland into a frog-rearing farm,” Melina said.

The depletion of the frog population in Cachar and its adjoining districts was first highlighted by Aveek Gupta, reader of ecology in the Assam Central University and the driving force behind the Environmental Society of South Assam.