Effects on bycatch reduction in a shaking cod end generated by canvas in a shrimp beam trawl

  • Kim, Yonghae (Institute of Marine Industry, Department of Marine Production technology, Graduate School, Gyeongsang National University) ;
  • Whang, Dae-Sung (Institute of Marine Industry, Department of Marine Production technology, Graduate School, Gyeongsang National University)
  • Received : 2014.07.26
  • Accepted : 2014.08.15
  • Published : 2014.08.31


An active stimulating device, such as a fluttering net or canvas attached to the end of a cod end generating a shaking motion, could help to encourage the escape of juvenile fish positioned passively near the net. Field fishing trials using a shrimp beam trawl were carried out to examine the effect on the reduction of juvenile fish or other discard catch by generating a shaking movement of the cod end using an unbiased cap-like round canvas. The mean period of the shaking motion with the round canvas was ~14 s, and the mean amplitude was 0.4 m as measured by peak event analysis and the global wavelet method. The bycatch of juvenile fish in 14 trials decreased by ~30% and by ~25% using a steady cod end for the total bycatch using a shaking cod end in the shrimp beam trawl, while the marketing catch was similar between steady and shaking cod ends. There was no difference in the body size of the shrimp or fish and species composition between the steady and shaking cod ends. Above results demonstrate a new method for bycatch reduction using an active stimulating device, although more detailed studies are needed.


Shrimp beam trawl;Shaking cod end;Bycatch reduction


Supported by : National Research Foundation of Korea


  1. Cho SK, Kim HY, Park CD and Cha BJ. 2013. Catches characteristics between fishing area and non-fishing area in the shrimp beam trawl of Geoje waters, Korea. J Kor Soc Fish Technol, 49, 377-384. (
  2. Chopin F and Suuronen P. 2009. The development of international guidelines on bycatch management and reduction of discards. ICES CM 2009/M:01.
  3. Deval MC, Bok T, Ates C and Ozbilgin H. 2006. Selectivity of PE and PA material codends for rose shrimp (Parapenaus longirostris) in Turkish twin rigged beam trawl fishery. Fish Res 81, 72-79. (doi:10.1016/j.fishres.2006.05.007)
  4. He P and Balzano V. 2013. A new shrimp trawl combination grid system that reduces small shrimp and finfish bycatch. Fish Res 140, 20-27. (
  5. He P and Balzano V. 2011. Rope Grid: A new grid design to further reduce finfish bycatch in the Gulf ofMaine pink shrimp fishery. Fish Res 111, 100-107. (doi:10.1016/j.fishres.2011.07.001)
  6. Ingolfsson OA. 2011. The effect of forced mesh opening in the upper panel of a Nephrops trawl on size selection of Nephrops, haddock and whiting. Fish Res 108, 218-222. (doi:10.1016/j.fishres.2010.11.024)
  7. Jang CS, Cho YH, Lim CR, Kim BY and An YS. 2009. An analysis on catch of the shrimp beam trawl fishery in Korea coastal sea. J Kor Soc Fish Technol, 45, 1-13. (DOI:10.3796/KSFT.2008.45.1.001)
  8. Jang CS, Kim KH, An YS, Park KJ and Park JO. 2006. Development of the selective fishing gear in shrimp beam trawl fishery. Final report to the Ministry of Maritime and Fisheries. p.91.
  9. Kim YH. 2011. Effects on the escapement of juvenile bastard halibut Paralichthys olivaceus of actively stimulating devices inside a model codend. Fis Aquat Sci 14, 62-69.
  10. Kim YH. 2012. Analysis of turbulence and tilt by in-situ measurements inside the codend of a shrimp beam trawl. Ocean Eng 53, 6-15. (
  11. Kim YH, Wardle CS and An YS. 2008. Herding and escaping responses of juvenile roundfish to square mesh window in a trawl cod end. Fish Sci 74, 1-7.
  12. Kim YH. 2013a. Fluttering characteristics of the ropes and nets as an active stimulating device inside the cod end of a trawl net. Fish Aquat Sci 16, 101-108. (
  13. Kim YH. 2013b. Shaking motion characteristics of a cod-end caused by an attached circular canvas during tank experiments and sea trials. Fish Aquat Sci 16, 211-220. (
  14. Kim YH. 2014. Comparison of the tilt variation between otter board and codend of a bottom trawl during fishing operations. Fish and Aquat Sci 17, 145-153. (
  15. Kim YH. 2015. Escape response of juvenile fish by the shaking of a codend using a cap-like canvas in tank experiments. Fish Res (in press)
  16. Kim YH and Whang DS. 2010. An actively stimulating net panel and rope array inside a model cod-end to increase juvenile red seabreamescapement. Fish Res 106, 71-75. (
  17. Matsushita Y. 2000. Bycatch reduction technologies for towed fishing gears. Nippon Suisan Gakkaishi 66, 261-268.
  18. Narasimha R, Kumar SR, Prabhu A and Kailas SV. 2007. Turbulent flux events in a nearly neutral atmospheric boundary layer. Phil Trans R Soc A 365, 841-858.
  19. Nunoo FKE, Boateng JO, Ahulu AM, Agyekum KA and Sumaila UR. 2009. When trash fish is treasure: The case of Ghana in West Africa. Fish Res 96, 167-172. (doi:10.1016/j.fishres.2008.10.010)
  20. Oh CW. 2010. Seasonal bycatch variations in the shrimp beam trawl fishery of coastal Wan-do, Korea. Kor J Fish Aquat Sci 43, 69-77
  21. Oh TY, Kim JI, Koh JL, Cha HK and Lee JH. 2003. Species Composition and Seasonal Variations of the Shrimp Beam Trawl Fisheries in the Adjacent Waters Geomundo, Korea. J Kor Soc Fish Technol 39, 63-76.
  22. Park J, Jo HS, Im YJ, Cha BY, Kwon DH, Ryu DK and Hwang HJ. 2013a. Species composition and community structure caught by shrimp beam trawl in the marine ranching ground of Taean, Korea. J Kor Soc Fish Technol, 49, 238-249. (
  23. Park JY, Kang HS, Kang JH, Kim JK, Ryu JH and Kim DS. 2013b. Yearly Fluctuation in the Fish Species Composition of Shrimp Beam Trawls off Maemuldo, Korea, during 2007-2009. Kor J Fish Aquat Sci 46, 619-625. (
  24. Ryer CH. 2008. A review of flatfish behavior relative to trawls. Fish Res 90, 138-146. (doi:10.1016/j.fishres.2007.10.005)
  25. Sea Grant. 2014. Fisheries Bycatch- Global issues and creative solutions. 29th Lowell Wakerfield fisheries symposium (May 13-16, 2014, Anchorage, Alaska. USA. Program and Abstracts, pp.106.
  26. Seo YI, Lee JH, Oh TY, Lee JB, Choi YM and Lee DW. 2013. Distribution and seasonal variations of fisheries resources captured by the beam trawl in Namhae island, J Kor Soc Fish Technol 49, 419-431. (
  27. Song MY, Kim JI, Kim ST, Lee JH and Lee JB. 2012. Seasonal variation in species composition of catch by a coastal beam trawl in Jinhae and Jinju Bay, Korea. J Kor Soc Fish Technol 48, 428-444. (
  28. Torrence C and Compo GP. 1998. A practical guide to wavelet analysis. Bull Am Meteorol Soc 79, 61-78.<0061:APGTWA>2.0.CO;2
  29. Wardle CS. 1993. Fish behaviour and fishing gear. In: Behaviour of Teleost Fishes. 2nd Ed., Pitcher T.J. ed. Chapman & Hall, London, UK, 609-644.

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