Hilsa returns to upper Ganga after years, signals revival of river ecosystem

The hilsa has been recorded in the middle and upper reaches of the Ganga after being virtually absent from these stretches for decades, in what officials described as a significant milestone in river restoration and aquatic biodiversity conservation.

According to the Central Inland Fisheries Research Institute (ICAR-CIFRI), two hilsa weighing a combined 740 grams were found near the Markandey Mahadev Temple in Chandauli district of Uttar Pradesh, nearly three decades after the species disappeared from the upstream reaches.

Historically, hilsa migrated from the Bay of Bengal through the Ganga system to Varanasi, Prayagraj and beyond. However, the commissioning of the Farakka Barrage in 1975 severely disrupted its migratory route, resulting in a sharp decline in hilsa populations in the middle and upper Ganga and affecting riverine communities dependent on the fish for their livelihoods.

Recognising the ecological, nutritional, cultural and economic significance of hilsa, ICAR-CIFRI, Barrackpore, and the National Mission for Clean Ganga (NMCG) launched a long-term scientific programme to restore the species.

Between 2019 and June this year, ICAR-CIFRI implemented an integrated strategy involving river ranching, stock enhancement, artificial breeding, the release of fertilised eggs and hatchery-produced spawn, tagging, post-release monitoring and stakeholder participation, the institute said in a statement.

More than 3.85 lakh juvenile and adult hilsa were ranched, while over 40 lakh fertilised eggs and around 9.4 lakh hatchery-produced spawn, aged between two and six days, were released upstream of the Farakka Barrage.

Tagging and systematic monitoring provided data on the fish's migration, survival and movement. Monitoring between 2023 and 2025 had earlier recorded ranched hilsa moving upstream as far as Mirzapur, indicating a gradual restoration of the species' historical range.

As a sensitive migratory species, the presence of hilsa is an important ecological indicator of river connectivity and habitat suitability, the institute said, describing its return as a sign of improving ecological functionality in the Ganga.

Officials said the ICAR-CIFRI-NMCG partnership, which brings together fisheries science, river conservation, field interventions and community participation, demonstrates what sustained scientific effort, institutional commitment and collaborative public policy can achieve.

The return of hilsa offers hope for restoring other native and migratory aquatic species and reinforces the principle that rivers should be managed as living ecosystems rather than merely as channels for water management, the institute said.

With PTI inputs