What comes to mind at the mention of Varanasi? The peals of temple bells in this ancient pilgrim town; people performing puja at the ghats and elsewhere; bodies being cremated at the banks of the river Ganga. Do dolphins come to mind?

Dolphins?! That happy looking performing artist which looks more like a shiny inflated balloon toy? Yes, and this freshwater dolphin is a rare specie, found in Indian and Pakistan – in the Ganga and in the Indus. It is a blind dolphin.

Where is the Rare Blind Dolphin Found?
Where is the Rare Blind Dolphin Found? [Illustration by Shiju George]

That is not to say that this dolphin does not have eyes. It has eyes but no lenses. Thus all that it can see is day and night. Beyond that, the world is an unknown sight to the mammal. Like many other sightless creatures of the animal kingdom, they, too, judge distances through sounds and their echoes.

Ten years ago, there were over 6000 dolphins who often gave the grave and sober mood of Varanasi a playful twist with their flips through the air, says a report in ‘Exploring the River Front of My Town’, a beautiful information and activity book produced by well-known Indian theatre personality Feisal Alkazi and Priti Jain.

Today, barely 3000 dolphins remain in the Ganga and its tributaries and the reasons are not far to guess. For no river has been talked about so much in recent years for the rising pollution in it than the Ganga.

One reason is the increasing level of toxic pesticides in the river into which the water from agricultural fields merges at various points. And farmers have been using greater amounts of pesticides over the years. The pesticides gather in the fat layer of the mammal, leading to a slow death.

freshwater dolphin, Indus river, Pakistan
Volunteers rescue a freshwater dolphin that was stuck at Rohri Canal in Sukkur on the west bank of river Indus in Pakistan. Asianet-Pakistan / Shutterstock.com

Earlier, the dolphins would migrate during the breeding season. But since the construction of the Farakka barrage, their journeys have been halted. So they breed less too. A barrage is an artificial dam created to divert the flow of water to new channels.

The introduction of nylon nets by fishermen has meant that more and more dolphins are getting caught in them and being killed. Dolphin oil is used by the fishermen as a bait for catfish.

The story is not very different in Pakistan either. Earlier, the mammal was lord of a watery territory that stretched across 2,800 km, in the Indus river. Now its home has shrunk to barely 170 km, between two dams.

They are hunted creatures here as well, states the report, which has been published by Centre for Environment Education, Ahmedabad, Gujarat.

There is a very important fact that is being missed out. The dolphin occupies pride of place or the topmost position in the food chain. Below it are the smaller creatures down to the smallest, all of whom are food for the creature a little bigger than them.

As long as the dolphin stays healthy, it is a signal that nothing has disturbed the food chain and the delicate balance in nature is being maintained. It means that the river system and the nearby ecosystem, too, are in good shape.

The worry starts when the big boss of the food chain starts showing signs of wasting and dies. It means that something has gone terribly wrong in the environment.

It means that we must not be blind to the fate of the “blind” dolphins.