Study on the Discards by the Danish Seine Fishery in Western Wakasa Bay

Abstract

In order to grasp the problems on discards by the danish seine fishery, the operations of the fishery were observed aboard and the samples of discards were collected. The obtained results are as follows;
Discards per haul ranged from 30 to 120kg in weight, and its weight and species compositions differ among fishing grounds and among the operation modes, especially the catch in Taraba (deeper than 200m) being mire than in Okaba (less than 200m in depth). In mist sought after species of the fishery, the small, unmarketable size was discarded and this percentage ranged from 15 to 50% of all discards in weight. Comparsion betweem the same as or more than the other, and especially the discards of Glyptocephalus stelleri, Chionoecetes opilio were remarkable. This result may suggest a possibility that improvements of the fishing gear and operation mode increase production of the marketable catch to some degree in the danish seine fishery.