NEW DELHI: For much of the past century, the Ganga has carried more than water. It has sustained livelihoods, fed communities, and anchored a dense web of biodiversity along its course. In recent decades, however, the river’s native fish have thinned—casualties of habitat degradation, altered flow regimes, pollution and relentless, often unregulated fishing pressure.
Over the last 10 years, a quieter effort has been underway to reverse that decline. Under the Government of India’s Namami Gange Programme, the ICAR-Central Inland Fisheries Research Institute (ICAR-CIFRI) has carried out a large-scale programme of scientific river ranching—an intervention designed not merely to restock the river, but to restore its ecological balance.
THE SCALE OF THE INTERVENTION
Between 2017 and 2025, ICAR-CIFRI organised 169 river ranching programmes across ecologically critical stretches of the Ganga and its tributaries. In that period, 205.5 lakh seeds of indigenous fish species were released into selected river segments. The emphasis has remained firmly on native species conservation, preservation of genetic integrity, and the long-term sustainability of riverine fisheries.
To improve survival rates after release, the institute stocked the river with fingerlings and advanced fingerlings measuring 10–15 centimeters in length, with an average body weight of 100–120 grams. These were not generic hatchery fish. The seed were artificially bred from wild brooders collected directly from the Ganga, a step intended to safeguard native genetic lines. Before release, the fish were reared under controlled hatchery and nursery conditions to enhance their adaptability in natural waters.
A TARGETED GEOGRAPHIC STRATEGY
The spatial distribution of these efforts reveals a deliberate strategy. Ranching was concentrated in stretches where ecological value and livelihood dependence intersect most sharply.
State-wise distribution of the 169 interventions during the reporting period shows:
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West Bengal: 68%
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Bihar: 17%
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Uttar Pradesh: 9%
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Jharkhand: 5%
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Uttarakhand: 1%
The concentration in West Bengal reflects both the ecological importance of its river stretches and the intensity of fishing activity in the lower reaches of the basin.
MEASURABLE GAINS
While ecological restoration is often measured over generations, early results suggest tangible gains. Fish landings of Indian Major Carps, a key indicator species group, have risen noticeably at major riverine centres.
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Prayagraj recorded a 24.7% increase
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Varanasi recorded a 41% increase
These improvements are largely attributed to sustained ranching interventions combined with associated conservation measures implemented under the Namami Gange Programme.
Beyond numerical increases, the initiative has helped rebuild native fish populations, strengthen the resilience of riverine ecosystems, and support the livelihoods of dependent fishing communities. It has also reinforced the role of science-based management in the stewardship of open-water fisheries.
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ICAR-CIFRI has developed the technique of artificial breeding of hilsa with cryopreserved milt and brood females collected from Hooghly estuary in 2025.
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A total of 3.82 lakhs of Hilsa adults were released in upstream of Farakka barrage in river Ganga. Of these, 6031 fishes were tagged.
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54.91 lakhs of fertilized Hilsa eggs and 8.06 lakhs of hilsa spawn were released for improvement of natural Hilsa population.
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With the efforts of the Institute yielding dividends, India has become the world’s top producer of inland capture fishes with an annual production of 1.39 million tonnes, surpassing China.
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In a landmark first, the institute estimated annual fish catches in major rivers, including 15,134 tonnes in the Mahanadi and 18,902 tonnes in the Krishna.
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Sustainable management protocols were developed for four major estuaries – Hooghly-Matlah, Rushikulya, Mandovi-Zuari and Netravathi-Gurupur and three brackishwater lakes, strengthening science-based governance of these ecosystems.
Leadership, Visibility and Public Engagement
Several of the ranching events were conducted in the presence of senior public representatives and policymakers, a signal of the national importance attached to restoring riverine biodiversity. These occasions doubled as platforms for:
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Public awareness
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Stakeholder engagement
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Promotion of sustainable fisheries practices across the Ganga basin
An Institution with Deep Roots Established in March 1947 at Barrackpore, West Bengal, ICAR-CIFRI has long been central to the evolution of inland fisheries research in India. What began as production-oriented research has matured into a broader ecosystem-based approach that integrates sustainability, conservation, livelihoods and nutritional security.
A Legacy of Scientific Stewardship
ICAR-CIFRI has developed enclosure culture technologies with diversified high value fish species like Ompok bimaculatus, Labeo bata, Systomus sarana Labeo rohita, Labeo rohita (Jayanti), Labeo gonius, Osteobrama belengeri, Cyprinus carpio haematopterus and Etroplus suratensis etc. at different geographical locations for increasing profitability and adoptability of cage farming.
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Three technologies ICAR-CIFRI-GI model cage, ICAR-CIFRI HDPE circular cage (16 m diameter, 5 m depth, 1005 m3 volume), and ICAR-CIFRI CAGEGROW feed have been developed and commercialised for promotion of cage culture.
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Cage culture produces an average of 3-4 MT of fishes per cage (96 m3) dimension with fast growing fish species like Pangasianodon hypophthalmus and Oreochromis niloticus.
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CIFRI CAGEGROW, BSF Floating Fish Feed, RESHMEEN are three fish feeds developed by the institute in last couple of years which are nutritionally balanced with better digestibility.
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CIFRI Fish Tarawhari and CIFRI ARGCURE are the two health care products released by the institute with the objectives of reducing disease loss and harnessing higher returns.
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CIFRI GI cage, CIFRI Circular Cage, CIFRI FRP Coracle, CIFRI FRP Ornamental tank were the other technologies recently commercialised by the institute.
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Two patents namely ‘Vertical gel electrophoresis’ and ‘Portable Split Beam Transducer Assembly on Water Craft for Measuring Exact Transducer Position Below the Water’ were obtained.
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The institute is doing research on developing IoT (Internet of Things)-based technologies for:
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Real-time monitoring and management of water quality parameters like DO, ammonia and turbidity
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Drone-based technology for water sampling, floating macrophyte coverage area estimation, underwater fish behaviour studies using ROV (remotely operated vehicle), water-body mapping using space technology etc.
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THE ROAD AHEAD
The experience of the past decade suggests that river restoration is neither rhetorical nor symbolic. When evidence-based interventions are aligned with ecological principles and supported by long-term monitoring, they can produce measurable outcomes.
Scientific river ranching under the Namami Gange Programme demonstrates that depleted native fish stocks can be replenished without compromising genetic integrity or ecological balance. The task now is continuity—scaling such initiatives, sustaining research, deepening stakeholder participation and refining adaptive management. The future of river Ganga’s biodiversity and fisheries potential will depend not on one season of stocking, but on persistent stewardship grounded in science.
