Abstract
Three types of fishing gears have been used in offshore trawl fisheries around Choshi for the years of 1971-1978, and each of them has its own proper features in net-construction and net-figure in operation.
The authors estimated which type of fishing gear is more effective in catching a certain kind of fish, from the relation between the fishing ability and characteristics of each type of fishing gear.
The results suggested that; Japanese type otter trawler is most efficient for Paralichthys olivaceus, Limanda herzensteini, and Kareius bicoloratus because catching effect of trawl-board and slow towing speed is excellent for them. Stern trawler is most efficient for squids because its net mouth is high and its towing speed is fast. Danish seine is most effcient for octopus, prawn and lobster because of catching effect of long sweep-line, the height of net-mouth and slow towing speed for them.
