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Pramod Kumar Pandey Dean College of Fisheries Central Agricultural University Agartala, Tripura Introduction India stands second in terms of fish production in the world with a production recorded at 9.3 million tones. 60% (5.8 m T) is contributed by inland fisheries (FAO, 2010). Inland fisheries sector of India is not only a livelihood provider (75% of 14.49 m fisherfolks are from the inland sector), but a crucial source of food/ nutritional security to millions of poor, lining the banks of its 7 m ha of inland water area. Rivers in India are facing multiple problems of severe pollution, over extraction, encroachment, dams and barrages which cut off the connectivity of the river with its associated ecosystems, climate change, deforestation in catchment areas. Aquatic Resources of India India has vast and varied aquatic resources in different form Rivers and Canals173,287 km Ponds and Tanks2.25 mha Lakes, Beels and Swamps- 1.3 mha Reservoirs 2.9 mha Brackish water 1.23 mha Coast line 8,129 km Riverine Resources of India Indian river system having a combined length 29,000 km in the form of 14 major rivers (catchment > 20,000 km²) 44 medium rivers (catchment 2000 to 20,000 km²) innumerable small rivers and streams. Riverine system: A) Himalayan river system Ganga river system (2225 km) Indus river system (combined length 4025 km) Brahmaputra river system B) Peninsular river system East coast river system (combined length 647 km) • Godavari river system • Mahanadi river system • Krishna river system • Cauvery river system West coast river system • Narmada river system • Tapti river system The Ganga River system Harbors the richest freshwater fish fauna of India Gangetic carps to mahseers and other coldwater fishes of the Himalayas, the hilsa, catfishes etc. The Ganga River System flows through 10 states in India and also in Nepal and Bangladesh. These rivers form one of the largest alluvial mega-fan regions of the world, and deliver huge quantities of sediment from the Himalayas to the northern Indian plains and to the Bay of Bengal in the Indian Ocean. The Gangetic floodplains shape not only landforms but also complex human cultures that attempt to stabilize themselves and adapt to the constantly changing riverine forces. Fish Biodiversity 27,800 fish species globally reported, about 11% are found in Indian waters. A total of 2225 finfish species have been reported from India 629 from freshwater 182 brackish water 1370 from marine ecosystem. 2934 species of crustaceans 5000 mollusks 765 species of echinoderms It is likely that the number of species might be more in different ecosystems Principal Fishery Resources of Ganga Indian major carps Catla catla Labeo rohita Cirrhinus mrigala Labeo calbasu Mahseer Tor putitora T. mosal T. tor N. hexagonolepis Other carps Labeo pangusia L. dero L .gonius Cirrhinus reba Larger catfishes Sperata aor S. seenghala Silonia silondia Wallago attu Pangasius pangasius Bagarius bagarius Rita rita Feather backs Notopterus notopterus Chitala chitala Other catfishes Clupisoma garva Eutropiichthys vacha Ailia coila Ompok bimaculatus O. Pabda Clupeids Hilsa ilisha Gudusia chapra Setipinna phasa Freshwater prawns Macrobrachium malcolmsoni M. birmanicum M. lamarei We are on the edge ! Fragmented rivers with ‘no flows’ in between dams Deteriorating water quality Flood plain farming under threat Fish catch and fisheries on the decline Riparian ecosystems losing continuity and diversity Flood plains cut off from flows Flows not reaching the delta and seas Salinity traveling deep inland Basins are closing Current Problems/Vulnerabilities •Waterlogging •Siltation •Erosion •Lack of Irrigation Water •Climate Change •Lack of Freshwater Flow •Lack of Appropriate Technology Waterlogging Risks • Reduce scope of crop cultivation • Mortality of fruits and plantation crops • Affects soil health • • • • Siltation Risks Affect drainage system Create water logging Increase flood threat Hamper water flow of canal and river Lack of Appropriate technology Risks • Hamper food security Erosion Risks Affect Fertility Decrease cultivable land area Migration of agricultural labor/farmers Lack of Irrigation Water Risks • Hamper irrigation • Reduce crop production and yield • Decrease cultivable land area Lack of Freshwater Risks Hamper irrigation Reduce crop production and yield Lack of Freshwater Flow Risks Salinity increased Washing of Land hamperred-Crop production and yield decreased Unavailability of irrigation water Decrease cultivable land area Climate Change Risks Cyclone Increase Embankment erosion Waterlogging Siltation Changing cropping pattern Reduce cropping intensity Crop biodiversity affected Salinity Risks Hamper crop production and yield Soil degradation Crops extinction Affect homestead garden and Fodder cultivation Major threats Siltation Siltation is most often caused by soil erosion or sediment spill. Sometimes siltation is called sediment pollution, although that is an undesirable term since it is ambiguous, and can also be used to refer to a chemical contamination of sediments accumulated on the bottom, or pollutants bound to sediment particles. Dams on the Ganga The key problem of fisheries today is that low level of water in the dry-season, because of flow regulation by dams, barrages and hydropower projects. Obstruction and fragmentation of river flow, habitat destruction, accelerated erosion and siltation, longdistance water diversions and poor flow releases are the major direct threats of damcanal systems in the Gangetic plains. Flow volume problems Globally, fragmentation and flow regulation have caused the most severe impacts through drastic alterations to riverine biota and ecology. Low flows and fragmented connectivity of river channels lead inevitably to fish population declines and breeding failure. Over time, dams have probably led to genetic isolation of fish populations as well as river dolphin / crocodile populations, destruction of fish breeding habitats and spawning triggers and loss of valuable wild fish germplasm. These losses are so large in their ecological value and opportunity costs that they cannot be recovered with artificial fish culture techniques or hatcheries. Different flows have different functions High flows - important for channel maintenance, bird breeding, algae control, wetland flooding and maintenance of riparian vegetation. Moderate flows - critical for recycling of organic matter from river banks and for fish migration Low flows - necessary for fish spawning, water quality maintenance, the use of the river by local people, etc. Why should a river flow from source to sea ? Is a river just water flowing waste to sea Is river an ecosystem in itself or a drain for carrying water Does a river have any functions or is just a conduit -evolutionary and ecological functions delivering rich nutrients to the sea sustaining fisheries and livelihoods; protecting wetlands with their capacity to filter out pollutants; providing habitat for a rich diversity of aquatic life safeguarding fertile deltas; protecting water quality; maintaining salt and sediment balances; Aggravation of pollution effects The Ganges basin is one of the most polluted large river basins in Asia, especially with regard to domestic sewage and agricultural runoff. Poor flows reduce the dilution and selfpurification capacity of river water to reduce concentration of pollutants and local impacts on fishes. Agricultural fertilizers (organophosphates, organochlorines, nitrates etc.), heavy metal pollution from industrial effluents, thermal power plants, oil refineries, distilleries and tanneries, and nitrogen-rich sewage, waste-water and non-biodegradable substances such as plastics, mercury, radioactive compounds and hospital wastes can cause fish kills or even worse, lead to high levels of toxicity in tissues. Habitat destruction and alteration of erosiondeposition dynamics •Soil erosion by erratic and sudden releases before floods can potentially lead to alteration and destruction of fish breeding habitats and stock depression. •Flow alteration also alters hydrological connectivity and sediment transport with wetlands and confluence channels during flooding. As a result these productive breeding habitats often become unavailable for catfishes and carps. •These factors together become a problem for pre-settlement of fish juveniles and recruits, which move into the main channels. Perception of Fishers 90% singled out “large dams and poor river flows” as the main causes for a near-total decline in fisheries and fish resources over the past 4 decades. About 90% people mentioned low water availability and stoppage of fish migratory routes by large dams as the main cause for fish declines. Almost 45% ( from eastern and northern UP, and Bihar) singled out the Farakka barrage as the main problem. Today, fisher folk from UP, Bihar and W B provide a large proportion (20-40%) of construction and manual labor force across India Others who stay behind have to take to menial jobs such as rickshaw-pullers or servants Some are forced to take to crime to be able to feed themselves and their families. These factors can weaken the social resilience of production systems and create poverty, disparity and community breakdown. Mitigation measures •Provide enough water, adequate natural flows in all rivers. •Allow fish movements upriver, currently blocked by large dams and barrages. •STOP new dams and mindless, high-cost, destructive and unsustainable engineering projects such as river interlinking. •Ban on destructive practices of fishing, especially mosquitonetting, poisoning, dynamite-fishing, shooting net operation. •Fishers are in need of government loans or credit, technical know-how, permits and I-cards, housing, education and displacement packages. • Clearly define fishing use and access rights across all rivers, • Provide clear guidelines on multi-objective management of fisheries amidst other economic activities Urgent need to reduce the presently excessive river pollution, especially industrial but also domestic wastes. Other alternative livelihoods include working with river management authorities, conservation agencies, ecotourism, agriculture etc. •Focus on community-based management of river fisheries and help it develop in an ecologically friendly and sustainable manner by formation of co-operative society. •Needs to be ensured through continued monitoring of fishing activity and behavior, including by-catch or hunting of species. This can also help the spread of exotic food fishes that are rapidly invading our rivers (the worst examples are Tilapia species, Chinese and Common Carps, and more recently, Red-bellied Piranha Conclusion Finally, the quest for sustaining fisheries in the Ganga River basin in the long-term will require rethinking of current dominant paradigms to move towards ecological restoration of rivers, their biodiversity, as well as socially just, rightsbased and equitable socio-political restoration of traditional fisher communities and fisheries management systems.