Inland Fishery Management

Sri Lanka has three main types: 1) Reservoir fisheries - major (>750 ha), medium (200-750 ha), and minor tanks (<200 ha), covering about 180,000 ha total, 2) Riverine fisheries - 103 river basins with perennial and seasonal rivers, 3) Lagoon and estuarine fisheries - 40+ lagoons covering 158,000 ha. Reservoirs contribute 70% of inland fish production.

Recommended species include: Tilapia (O. niloticus, O. mossambicus) - most common, hardy; Common Carp - bottom feeder, fast growing; Catla and Rohu - Indian major carps for larger reservoirs; Freshwater prawn (M. rosenbergii) - high value; Indigenous species like Etroplus, Labeo for biodiversity. Avoid invasive species. Stock fingerlings of 5-10cm size for better survival.

Cage culture involves floating or fixed cages (4x4x3m typical) in reservoirs. Stock tilapia at 50-100 fish/m³, feed with floating pellets (3-5% body weight daily). Site selection crucial: 4-8m depth, good water flow, away from pollution. One cage can produce 200-400 kg in 6 months. Investment: LKR 150,000-200,000 per cage, ROI in 8-10 months.

Regulations include: Fishing license required from NAQDA/DFAR, mesh size restrictions (>3.5 inches for gill nets), prohibited methods (dynamite, poison, electric), seasonal bans during broodstock management (usually May-July), daily catch limits for certain species, reserved areas for broodstock management. Community-based organizations help enforce regulations locally.

Enhancement methods: 1) Stock fingerlings annually (50-100 kg/ha), 2) Install fish aggregating devices (brush parks), 3) Establish sanctuary areas (10-20% of water body), 4) Control aquatic weeds, 5) Lime application in acidic waters, 6) Prevent pollution from agriculture, 7) Regulate fishing effort through licensing. Can increase yield from 50 kg/ha to 200-300 kg/ha.

Community-based management involves: Fisheries Cooperative Societies (FCS) managing access rights, enforcing regulations, maintaining gear parks, organizing stock deployment programs, collecting data, resolving conflicts. NAQDA provides training, seed stock, and technical support. Successful co-management increases compliance, reduces conflicts, and improves sustainability.

Permitted methods: Gill nets (3.5-5 inch mesh), cast nets for small-scale fishing, hook and line for recreational, beach seines in larger water bodies, traps in flowing waters. Traditional crafts: outrigger canoes, flat-bottom boats. Modern: fiberglass boats with outboard motors. Avoid destructive methods that harm broodstock management stock and juveniles.

Strategies include: coordinate with irrigation authorities for gradual water release, establish deep water refuges, use floating cages that adjust to levels, stock species tolerant to fluctuation (tilapia, catfish), time stock deployment after monsoon when levels are high, production output before dry season drawdown. Maintain minimum 30% capacity for fish survival.

Inland fisheries produce 80,000+ MT annually, valued at LKR 15 billion. Supports 50,000+ fishing families directly, 150,000 indirectly. Average income: LKR 30,000-50,000/month for active fishers. Potential to increase production to 150,000 MT through better management. Growing demand for freshwater fish with 30% price premium over marine fish in local markets.

Control methods: Physical removal through targeted fishing, biological control using predator species (carefully managed), habitat modification to disadvantage invasives, public awareness to prevent new introductions, early detection and rapid response systems. Common invasives: Sucker mouth catfish, African catfish. Prevention is more cost-effective than control.

NAQDA services: Free fingerlings for stock deployment (annual programs), technical training on fishing methods and management, subsidized fishing gear and boats (50% subsidy), formation of fisher organizations, water quality testing, conflict resolution, market linkages, research on stock enhancement. Regional centers provide extension services and coordinate with local communities.

Opportunities include: recreational angling with catch-and-release, boat tours for bird watching, homestays in fishing villages, traditional fishing demonstrations, fish sanctuaries as tourist attractions, restaurants serving fresh catch. Benefits: additional income for fishers, conservation incentive, infrastructure development. Requires training, regulations, and marketing support from authorities.