Sinking depth of tuna longlines related to mainline materials in the North Pacific Ocean

북태평양 중부공해에서 조업하는 다랑어연승어구의 모릿줄 재질에 따른 침강수심

  • Jo, Hyun-Su (Fisheries Resources and Environment Division, West Sea Fisheries Research Institute, National Fisheries Research & Development Institute) ;
  • Hwang, Seon-Jae (Korea Fisheries Resources Agency) ;
  • Lee, Ji-Hoon (Institute of Low-Carbon Marine Production Technology, Pukyong National University) ;
  • An, Doo-Hae (Cetacean Research Institute, National Fisheries Research & Development Institute) ;
  • Moon, Dae-Yeon (Fisheries Resources Management Division, National Fisheries Research & Development Institute)
  • 조현수 (국립수산과학원 서해수산연구소 자원환경과) ;
  • 황선재 (수산자원사업단) ;
  • 이지훈 (부경대학교 저탄소해양생산기술연구소) ;
  • 안두해 (국립수산과학원 고래연구소) ;
  • 문대연 (국립수산과학원 자원관리과)
  • Received : 2011.04.14
  • Accepted : 2011.08.02
  • Published : 2011.08.31


The purpose of this paper is to provide useful information for fishermen in the manner of investigation a sinking speed of current type tuna longline gear at the North Pacific Ocean as a new developed tuna longline fishing ground. The sinking depth of mainline in connection with different basket was investigated. The experiments were also performed with different materials such as Supermansen (i.e., PE) and Hitech (i.e., PA) for the mainline to investigate the sinking depth of mainline and hooks. Furthermore, the relation between the sinking depth of hooks and catches are investigated also. The sinking depth of mainline at the first and the last shooting basket shows deeper than that of middle part of a basket due to reduced shortening ratio. The sinking depth of mainline and hook with Hitech material shows more shallow than that of Supermanse material, even the Hitech case was designed to sink deeper than that of Supermanse case. The highest catches arise at the middle part basket as the hook number 7 with around 248m sinking depth. From the results, longline with Hitech material is needed to increase the sinking force for reaching the relevant sinking depth. Moreover, the current strength at the North Pacific Ocean will be considered for further commercial fishing.


Supported by : 국립수산과학원


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