A little before the monsoon rains pour down, a piscean journey of gastronomical significance originates in the Bay of Bengal. The hilsa leaves its home in the ocean and spawns in the estuarine waters where the rivers from India and Bangladesh meet the ocean. Large shoals of the silver-scaled fish also move slowly upstream the Padma in Bangladesh and the Ganga in India. The flavours of river and sea mingle to give the hilsa its unique sweet-salty taste. The fish that travel the farthest upriver are said to be the tastiest. Till about 40 years ago, this meant a nearly 1,200-km journey to Allahabad. But the completion of the Farakka barrage in 1975 disrupted the hilsa’s westward migration. A navigation lock in the barrage hindered the fish’s free movement. Hilsa aficionados in India are never tired of lamenting that the last hilsa was caught at Buxar, near Allahabad, more than 30 years ago. On February 8, Union River Development Minister Nitin Gadkari inaugurated a project that aims to assuage their hurt feelings. The lock will be redesigned, at a cost of Rs 360 crore, to let the hilsa return to its spawning grounds of yore.
The new fish pass is expected to be complete by June, when the bony fish begins its journey to the river. Its gates will be opened between 1 and 5 pm, which is known to be the time for peak hilsa movement. The trouble, however, is that the fish-way will span no more than eight metres of the Ganga’s nearly 2 km width at Farakka. It’s anybody’s guess if that is enough to sustain the hilsa’s mass migration.
US ecologist John Waldman’s study in 2013 showed that only 3 per cent of a shoal use a pass to get past a dam. In what should be of salience to the ministry’s new project, one of the fish studied by Waldman is the American shad, a species closely related to the hilsa. A few silver-coloured fish may still sneak in through the new pass. But that is unlikely to undo the culinary damage caused by the Farakka barrage.