Catch characteristics of various codend mesh sizes in demersal trawl catches in Lake Victoria

Most fishing operations are characterised by selectivity. This obscuressome qualitative and quantitative aspects of the composition of the popula.tion as reflected in the catch. In otter trawls, apart from the question ofavoidance or escapement at the mouth of the net. the most important partof selection for size of fish is the codend. However, the length of the net,along with the mesh size, determine ease of water passage and thus affectsthe efficiency of the trawl. In addition to mesh size other factors affectingcodend selection include: (1) material from which it is made, (2) weight ofthe catch. (3) duration of the haul, and (4) speed.