底曳網の漁獲性能に関する基礎的研究

• Main Authors: 肥後, 伸夫, 4790, HIGO, Nobio, 1000010041691
• Format: Other/Unknown Material
• Language: Japanese
• Published: 鹿児島大学 1972
• Subjects: 664; Bering Sea
• Online Access: http://hdl.handle.net/10232/00000763; https://ir.kagoshima-u.ac.jp/record/771/files/AN00040498_v20-2_p1-137.pdf; https://ir.kagoshima-u.ac.jp/records/771

This research was carried out with the use of the three kinds of trawling net using of by the fishing boats, namely, trawlers, bull trawlers or Danish seiners belonging to the groups of the fishing boats of the mother ship fishery, fishing on the continental shelf of the eastern part of the Bering Sea including near the shelf, during the term from April to October for the three years of 1963, 1965 and 1967. As to the items of the fishing gears used in this research, in table 3, are shown the tonnage of the fishing boat, its number and the scale of the net used in this experiment. Namely, the number of the monther ship is 3 the number of the fishing boats belonging to those mother ships, is as in the following : ― the number of the side trawlers with tonnage of 370, is 2 that of the stern trawlers with the tonnage of 299, is 3 the total of which being 5 that of the bull trawler with the tonnage of 121 and with the tonnage of 98, is 4 and 2 the total number of with being 6 the total number of the Danish seiner is, 11 with the tonnage range from 65 to 92. In case of those trawling nets, in accordance with varieties in the sort of the net, a considerable difference is to be noted both in the weight of the ground rope and in the buoyancy of the float, but the whole lengths of the nets are almost equal. As may be seen in the introduction of this thesis, the purpose of this research is as in the following : ― through the three sorts of the fishing net used as the materials of this experimental research, namely, the trawl net, the bull trawl net, and the Danish seine, the following 3 items were aimed : (1) the attempted clarifications of the fishing efficiency of the fishing net by means of actual measurements and the model experiments (2) the confirmation of the fundamental characteristics in the designing and making-up the respective net (3) accompanied with the analyses of the physical and biological factors in drawing the design of the trawling net in possession of high effectivity. The ...