Dr Sinha accompanied him to the confluence of Ganga and Gandak where they saw families of Ganges dolphin. Through his tireless effort, dolphin was given the status of National Aquatic Animal by Prime Minister Manmohan Singh on October 5, 2009. A pioneer researcher and conservationist for this cetacean species, Sinha has spent the better part of his life sailing in rivers.

He was appointed an expert member of the National Ganga River Basin Authority. “It was a great honour, as Chief Ministers of those states through which Ganga flows, are its members,” said Dr Sinha, in a free-wheeling interview to Abhay Kumar of Deccan Herald.

Excerpts:

You have been doing research on dolphins for the last three decades. How and when did you get fascinated with this aquatic animal?

In the 60s, when I was in school, I came to Patna for the first time as my grandmother was to be cremated at Baans Ghat on the banks of Ganga. It was then I saw pods of dolphins, more than two-metre long, coming to water surface every 15-20 seconds. Since then, dolphin has become an integral part of my life.

How you were nick-named ‘Dolphin Man’?

I have spent more than half of my life doing research on Ganga ecosystem, river and wetland ecology, Ganges river dolphin, aquatic wildlife etc but it was Planning Commission member Dr Syed Z Qasim, who, while introducing me to Dr Stephen Leatherwood of International Union of Conservation of Nature (IUCN) in 1992, was the first one to have said, “Meet our Dolphin Man-- Dr RK Sinha”.

What is the exact figure of dolphins in India?

To be very honest, exact census of dolphin is not possible. We can only have sighting records. As per the latest figures, there are 2,587 dolphins in India. However, India, Bangladesh and Nepal together account for 3,061 dolphins.

But it is believed that the stretch of Ganga from Buxar to Katihar (in Bihar) has substantial dolphins?

Yes, it’s true. From Buxar to Maniharighat (Katihar), 808 dolphins have been sighted in the Ganga, while in Kosi it’s just 85. However, in Gandak, the figure is as high as 267. Altogether, there are 1,160 dolphins in Bihar. Jairam Ramesh saw many dolphins at the confluence of Ganga and Gandak.

But even Chilka lake in Odisha is famous for dolphins…?

It’s mostly Irrawaddy dolphin (Irrawady is a river in Myanmar). And it’s scientific name is Orcaella Brevirostris.

But Ganga river dolphins are one of the four surviving fresh water dolphins?

Yes, the Ganges river dolphin is a fresh water dolphin which never enters sea. It is found in Ganga-Brahmaputra-Meghna, and Sangu-Karnaphuli river systems in India, Nepal and Bangladesh. Besides Ganges river dolphin, the other two fresh water dolphins are Indus river dolphin (scientific name: Platanista gangetica minor), commonly known as Bhulan in Pakistan; and Amazon river dolphin (scientific name: Inia geoffrensis), which is commonly known as Boto in Latin America.

And the fourth one?

It’s Yangtze river dolphin (scientific name: Lipotes vexillifer), which is fondly called Baiji in China. Unfortunately, it became extinct in 2006.

The scientific name of Indus river dolphin sounds similar to Ganges river dolphin.

Yes, around 3,000 years back, their origin was the same. Both Ganges and Indus river dolphins are blind as they lack crystalline lens in their eyes, though they have remnants of retina in their vestigial eye. They cannot form image. However, they distinguish between light and dark.

Any other interesting facts?

Adult males grow up to 2.12 metres long and females up to 2.7 metres. A calf measures 70 cm and weighs about 4 kg at the time of birth. An adult female weighs up to 150 kg.

Is dolphin a slow breeder?

Yes. Female dolphin attains sexual maturity at 10 years, while male at about eight years of age. Gestation period is 9 to 10 months. One baby is born at a time. Next baby is born after 2-3 years.

What are the major threats to this aquatic animal?

The two main threats are poaching and habitat degradation. Earlier, dolphins were killed intentionally by the fishermen using fishing nets, harpoons etc. The harpooning has, however, now stopped but unintentional killings in fishing nets are still continuing. The fishermen use dolphin oil as fish attractant and massage to get relieved from joint pains. The habitat degradation is mainly due to reduced flow in rivers, pollution and construction of dams/barrages.

It is believed that the number of dolphins is an indicator of how clean or dirty the river ecology is?

Yes, it’s an indicator of health of rivers. In fact, the Ganges river dolphin is a legendary creature which has been mentioned in many of our mythological literature. You will be surprised to know that it was given legal protection by Emperor Ashoka in 3rd century BC by including this aquatic animal in a government decree in the Vth Pillar Edict. The Government gave it a legal protection by including it in the Schedule I of the Wildlife (Protection) Act 1972, while Dr Manmohan Singh declared this species as National Aquatic Animal on October 5, 2009.

How its killing can be stopped?

Fishermen will have to be educated that they can use alternate oil which can be extracted from the fish scraps. Besides, we have told the government that it should assist fishermen through micro-financing and help them involve in eco-tourism, fish culture etc as an alternate source of livelihood.

Having done so much of research, any regrets in life?

The only regret is that I have not been able to devote adequate time to my family although my two sons are now well settled in Bangalore, where they are working for a software firm TCS.