A freshwater Gangetic dolphin (in the foreground) in the Kulsi. Telegraph picture

Guwahati, Oct. 26: A unique conservation scenario emerged in Kukurmara in 1991 to make this small area on Guwahati’s outskirts a safe haven for the endangered Gangetic river dolphin, or xihu, as it is called in Assamese.

In 1991, a resident of the area had allegedly killed a dolphin in the Kulsi and upon returning home, he found his son dead under mysterious circumstances. The news had spread like wildfire and since then, the area had become a safe haven for the Gangetic dolphin — a species listed in the IUCN red list and Schedule I of India’s Wildlife Protection Act, 1972.

Kukurmara, located about 25 km from Guwahati, is the confluence of two rivers — Kulsi and Kuiya — and is thus an ideal habitat for the river dolphins, which prefer deep waters in and around the confluence of two or more rivers.

Till today, the residents, who are mostly fishermen or sand miners, believe that if anyone kills a xihu, he will lose a family member, and hence, take utmost care to never harm the blind aquatic mammals.

Abdul Wakid, head of the Gangetic dolphin research and conservation initiative of Aaranyak, an NGO, said, “Whether sand mining in Kulsi is a boon or bane, is not yet confirmed, but the ease with which these mammals move around in the area is very surprising. It is an unusual situation.”

A sand miner from Kukurmara, Deepak Das, 28, who rows through Kulsi, fears that his oars might some day accidentally harm a dolphin. Such is the fear that the fishermen of Kukurmara do not use gillnets. “The idea of not using these nets is because we do not want to harm the dolphins. In fact, such is our bond with the xihu that it helps us fish,” Das said.

According to the last census conducted by Aaranyak, the number of Gangetic river dolphins, which were found in abundance in the state earlier, had come down considerably owing to various human activities like fishing, poaching, construction of dams and pollution.

Raj Amin, an ecologist with the Zoological Society of London, said, “These mammals face a greater threat though. Of the four types of freshwater river dolphins, one has already gone extinct. The population of the rest is also depleting.”

The Gangetic river dolphin (platanista Gangetica) is primarily an inhabitant of the Ganga and Brahmaputra river systems of India and Bangladesh. At present, there are less than 2,000 dolphins across the world. Of these, 30 swim around at the confluence in Kukurmara.

Das, 28, said, “Like me, there are hundreds of families in Kukurmara who survive on sand mining and a few on fishing. But, even though boat traffic is high at the confluence, the dolphins have still not migrated to a different location. We feel lucky.”

The Gangetic dolphins are blind, but the loss of vision is compensated by their highly developed sonar sense. They catch their prey by a process called echolocation. They emit an ultrasonic sound and by processing the reflected sound wave, they can judge the size and location of their prey. They navigate through water using the same process.