Improvement of Large-Mesh Driftnets for Small-Scale Fisheries in Bangladesh - BOBP/WP/5

Abstract

Driftnets account for nearly 30 per cent of the total marine catch in Bangladesh. With the polyamide (PA) or nylon twine used for constructing the nets getting scarcer and costlier, the driftnetters tend to carry less and less gear, affecting fish catch and incomes. It is therefore desirable to devise ways to ensure that driftnets cost less and/or produce more. This was the rationale for an experimental project conducted during the 1979/80 winter season. The boats used three kinds of fishing gear-the traditional large-mesh driftnets (45 ply), modified nets of thinner netting twine (27 ply) and nets of polyethylene material. Details of fish catch were recorded daily for thethree types of nets with the assistance of extension workers from the Kalidaha fishing project. A comparative study of the data obtained reveals that nylon nets of thinner twine size, which cost approximately 40% less than the traditional nets, caught about 40% more fish. Thus the thinner twine n ets are clearly preferable to the traditional. Following from these results, a promotional effort to extend the merits of this net is recommended, with the Bay of Bengal Programme assisting in the effort. As for the nets of polyethylene netting material, they also caught 45% more fish tha n the traditional nets, but sustained greater damages. Further studies are recommended on the efficacy of polyethylene netting material and on the optimum mesh sizes for large-mesh driftnets. Stud y tours of large-mesh driftnet fisheries in other countries are also recommended for Bangladesh national officers.