The Hilsa crisis in West Bengal may not last forever as the Union Water Resources Ministry is planning to install fish ladders in the river Ganga near the Farakka Barrage in the State to help the fish breed in freshwater. Following the construction of Farakka Barrage, the Hilsa population in the Ganga went down drastically as the fish found it difficult to cross the barrier and reach its freshwater breeding ground. Much like the Salmon of North America, the Hilsa enters the river from the sea to swim upstream for hundreds of kilometres and spawn in freshwater, following which it returns to its salty abode. A fish ladder is a series of pools built like steps to enable the fish to migrate upstream for breeding. The fish normally swim and leap up a series of these pools that have fairly high velocity of water to attract them to the ladder and push them upstream. However, the force of the water cannot be so great either that it washes the fish back downstream or exhausts them to the extent that they are unable to continue their journey upstream. Water Resources Minister Uma Bharti told the Lok Sabha on Thursday that the proposed installation of fish ladders will ensure that Hilsa gets freshwater to breed in. If the project is successful, the delectable fish that is a delicacy in Bengal will be available even in the Chambal region of Madhya Pradesh and Uttar Pradesh, as was the case in the past, she said. She added the thriving of other aquatic life like goldfish and dolphins in the river would also be further indicators of the improving ecological health of the river and its tributaries. Hilsa fisheries experienced a severe setback after the commissioning of the Farakka Barrage in 1972, when as per experts, the average catch dropped from 159.5 kg/km to 9.4 kg/km of the stretch. In West Bengal, the spawning grounds of Hilsa are located in the Hooghly River. The Hilsa breeds in the monsoon season and the migration of the fish starts from July and ends in October, during the first phase and from January until March in the second phase. Peak breeding of Hilsa happens during full moon in October. According to experts, overexploitation and siltation of riverbeds, construction of barrages, decrease in water flow upstream and fragmentation of rivers in the dry season have been majorly impacting the migration of the Hilsa. However, the proposed fish ladders are expected to boost its migration and encourage breeding in its native sites.
2016 The Pioneer.