The day of the dolphin

The deliberate killing of these aquatic mammals may have declined, but inadvertent drowning in fishing nets alarmingly continues

Published - February 05, 2022 04:45 pm IST

A dead dolphin. Photo: Sushant Dey

A dead dolphin. Photo: Sushant Dey

Nachiket Kelkar, as an undergraduate studying zoology, became intrigued on reading about the Ganges river dolphin. The species cannot see its fishy prey or even its own young. Reduced to tiny pits, the eyes at the most detect light or its absence. Virtual blindness is not a disability nor does it slow the animal in the silt-laden turbid Ganges and the Brahmaputra rivers. The aquatic mammal locates its meal with its inbuilt sonar, emitting high-frequency clicks and using its fluid-filled melon-shaped head to detect their reflection off objects. In shallow waters, it swims on its side, a rare ability for a member of the family of whales, porpoises, and dolphins. Kelkar thought it seemed so different from its popular relatives, the seafaring dolphins.

Why do these streamlined animals swim on their sides? Do the calves find prey with echolocation or by some other means? The researcher studied the river dolphin for his master’s thesis, but what he discovered in the lower Gangetic floodplains of Bihar changed the trajectory of his enquiry.

“I went from sensory ecology to studying political ecology of the species,” he says.

When social and political issues on land affected these aquatic animals, understanding those impacts gained more urgency than studying their biology.

Threats to the sleek mammals zing from many directions: declining fish stocks, competition with fishermen, and death in fishing nets. The river dolphin, locally called soans, is more valuable dead than alive to fishermen, who use the stinky oil from the blubber to catch catfish. In the past, they hunted the animals, but conservationists convinced them to stop the practice. The deliberate killing of these aquatic mammals may be declining, but inadvertent drowning in fishing nets continues.

Entangled

A 65-kilometre stretch of the waterway called the Vikramshila Gangetic Dolphin Sanctuary, the only one of its kind for India’s national aquatic animal, is a reserve only in name. Catching fish is not allowed within a conservation area, where fishermen can’t help fishing.

Dependent for generations on the river and with no other means of subsistence, they cast their nets in the same spots where dolphins hunt, competing for the same catch. The commonly used gillnets with less than 40-mm mesh size are illegal, making the local enterprise an offence twice over. But the legal large-gap nets entangle dolphins that then drown. The fine-mesh gillnets create an invisible curtain underwater that the aquatic mammals can detect and then swerve.

Besides these immediate dangers, pollution, dams, and the vagaries of climate have a much more telling impact on fisheries and the soans.

It’s a wonder that any Ganges river dolphins survive in this abused and densely human-populated waterway. “Conservation and livelihoods are at serious and violent odds,” says the researcher.

To give the species a fighting chance, Kelkar and his colleagues could have lobbied for fishing to be shut down, poachers prosecuted, and nets confiscated. That would be the way of conventional conservation. But they sympathised with the poor fishermen who had few other options. Criminal gangs threatened these marginalised people and appropriated much of their meagre catch. They beat and even killed anyone who resisted. Caught between thugs and paltry returns, many fishermen set aside their nets and migrated to cities to work on construction sites and factory production lines.

A struggle

“Studying river dolphins led me to engage with fishing communities, their history, and how they relate with the animals,” says the researcher. “Typically, this is not what a biologist is taught to do. It’s been an enriching struggle.”

Instead of further victimising the remaining fishers, Kelkar and his team recommend that the authorities allow fishing nets in which soans are least likely to drown. Offering incentives for reporting dolphin by-catch could open an opportunity for dialogue with these communities. Regular monitoring of the river by wildlife authorities may curtail gang activities and keep an eye out for dead dolphins.

Perhaps these measures would offer a glimmer of light that even the soans can see.

Janaki Lenin is not a conservationista but many creatures share her home for reasons she is yet to discover.

0 / 0
Sign in to unlock member-only benefits!
  • Access 10 free stories every month
  • Save stories to read later
  • Access to comment on every story
  • Sign-up/manage your newsletter subscriptions with a single click
  • Get notified by email for early access to discounts & offers on our products
Sign in

Comments

Comments have to be in English, and in full sentences. They cannot be abusive or personal. Please abide by our community guidelines for posting your comments.

We have migrated to a new commenting platform. If you are already a registered user of The Hindu and logged in, you may continue to engage with our articles. If you do not have an account please register and login to post comments. Users can access their older comments by logging into their accounts on Vuukle.