Capture Fisheries, Reservoir and Riverine Fisheries Management
The resource base
Odisha's capture fisheries rest on rivers, reservoirs, wetlands and the Chilika lagoon. Hirakud is the largest reservoir, with Rengali, Balimela and Upper Kolab also important. Rivers such as the Mahanadi, Brahmani, Baitarani and Subarnarekha support Hilsa, mahseer, murrels and catfish. Gears include gill nets, cast nets, seine nets, drag nets, traps and hook and line; mesh size determines which size class is caught, since a gill net traps fish by the girth behind the head.
Management tools
- Stocking of Indian major carps and ranching of riverine brood stock to build recruitment.
- Mesh regulation so that immature fish escape, plus a closed season during peak breeding.
- Fish sanctuaries and brood stock banks in reservoirs and river stretches.
- Pen and cage culture in reservoirs to raise yield without heavy fishing pressure.
- Co-management through fisheries cooperative societies holding leases, with the department fixing royalty.
- Addressing threats: dams blocking migration, pollution, destructive fishing, wetland encroachment and weed infestation.
Worked example
A 5000 ha reservoir is stocked with 500 IMC fingerlings per hectare: 5000 x 500 = 25,00,000 fingerlings. If the sustainable yield is 50 kg/ha/yr, expected production = 5000 x 50 = 2,50,000 kg = 250 t. At a farm-gate price of 100 rupees per kg the gross value is 2,50,000 x 100 = 2.5 crore rupees. If the annual catch is instead 200 t from 1000 net-nights, the catch per unit effort is 200,000/1000 = 200 kg per net-night, a figure you can compare across years.
Traps that cost marks
- Treating a reservoir like a pond and assuming that stocking alone raises yield without mesh control.
- Confusing CPUE units, such as kg per net-night versus kg per boat per day.
- Classifying Chilika as a purely freshwater riverine system.