Discard Avoidance by Improving Fishing Gear Selectivity: Helping the Fishing Industry Help Itself

  • Finbarr G. O’NeillEmail author
  • Jordan Feekings
  • Robert J. Fryer
  • Laurence Fauconnet
  • Pedro Afonso


To address the challenges of the Landing Obligation, fishers need to be able to adjust the selective performance of each fishing operation in response to what they observe on the fishing grounds and to what they bring on board. This will include strategies on where and when to fish but also on how to fish, which we examine here. In particular, we focus on ways to encourage and support fishers to design, develop and test selective gears that will avoid unwanted catches in the first place. To this end, we highlight the necessity to increase awareness of existing solutions, the importance of understanding the capture process and how fish react to fishing gears, and the need to evaluate the economic implications of new gears. We examine the success of science-industry collaborations and emphasise the benefits of a flexible regulatory environment. Looking ahead, the fishing industry needs to keep up-to-date with new technologies that can be used to observe the interaction of fish and their gears and with new approaches to modifying selectivity.


Catch avoidance Discard reduction Fish reactions to fishing gear Industry participation Selective fishing gears 



Part of this work has received funding from the Horizon 2020 Programme under grant agreement DiscardLess number 633680. This support is gratefully acknowledged.


  1. Anders, N., Fernö, A., Humborstad, O.-B., Løkkeborg, S., Rieucau, G., Utne-Palm, A.C. (2017). Size-dependent social attraction and repulsion explains the decision of Atlantic cod Gadus morhua to enter baited pots. Journal of Fish Biology, 91(6), 1569–1581.CrossRefGoogle Scholar
  2. Arimoto, T., Glass, C.W., Zhang, X. (2010). Fish vision and its role in fish capture. In P. He (Ed.), Behavior of marine fishes: Capture processes and conservation challenges. Oxford: Wiley-Blackwell.Google Scholar
  3. Armstrong, M.J., Payne, A.I.L., Deas, B., Catchpole, T.L. (2013). Involving stakeholders in the commissioning and implementation of fishery science projects: Experiences from the UK Fisheries Science Partnership. Journal of Fish Biology, 83, 974–996.PubMedGoogle Scholar
  4. Ben-Yami, M. (1976). Fishing with light. FAO fishing manuals. Fishing News Books Limited, Surrey.Google Scholar
  5. Ben-Yami, M., Pichovich, A. (1988). Attracting fish with light (FAO Training Series No. 14). Rome: FAO.Google Scholar
  6. Breen, M., Dyson, J., O’Neill, F.G., Jones, E., Haigh, M. (2004). The swimming performance of haddock at prolonged and sustained swimming speeds, and its role in their capture by towed fishing gears. ICES Journal of Marine Science, 61, 1071–1079.CrossRefGoogle Scholar
  7. Broadhurst, M.K. (2000). Modifications to reduce bycatch in prawn trawls: A review and framework for development. Reviews in Fish Biology and Fisheries, 10(1), 27–60.CrossRefGoogle Scholar
  8. Browne, D., Minto, C., Cosgrove, R., Burke, B., McDonald, D., Officer, R., Keatinge, M. (2017). A general catch comparison method for multi-gear trials: Application to a quad-rig trawling fishery for Nephrops. ICES Journal of Marine Science, 74, 1458–1468.Google Scholar
  9. Bryan, D.R., Bosley, K.L., Hicks, A.C., Haltuch, M.A., Wakefield, W.W. (2014). Quantitative video analysis of flatfish herding behavior and impact on effective area swept of a survey trawl. Fisheries Research, 154, 120–126.CrossRefGoogle Scholar
  10. Bryhn, A.C., Konigson, S.J., Lunneryd, S.-G., Bergenius, M.A.J. (2014). Green lamps as visual stimuli affect the catch efficiency of floating cod (Gadus morhua) pots in the Baltic Sea. Fisheries Research, 157, 187–192.CrossRefGoogle Scholar
  11. Depestele, J., Degrendele, K., Esmaeili, M., Ivanovi, A., Kr­ger, S., O’Neill, F.G., Parker, R., Polet, H., Roche, M., Teal, L.R., Vanelslander, B., Rijnsdorp, A.D. (2018). Comparison of mechanical disturbance in soft sediments due to tickler-chain SumWing trawl versus electro-fitted PulseWing trawl. ICES Journal of Marine Science. Scholar
  12. Drewery, J., Watt, M., Kynoch, R.J., Edridge, A., Mair, J., O’Neill, F.G. (2012). Catch comparison trials of the Flip Flap netting grid trawl. Marine Scotland Science Report 08/12.Google Scholar
  13. Eliasen, S.Q., Feekings, J., Krag, L., Veiga Malta, T., Mortensen, L.O., Ulrich, C. (2019). The landing obligation calls for a more flexible technical gear regulation in EU waters – Greater industry involvement could support development of gear modifications. Marine Policy. 173–180.CrossRefGoogle Scholar
  14. Engås, A., Jørgensen, T., West, C.W. (1998). A species-selective trawl for demersal gadoid fisheries. ICES Journal of Marine Science, 55, 835–845.CrossRefGoogle Scholar
  15. Favaro, B., Côté, I.M. (2015). Do by-catch reduction devices in longline fisheries reduce capture of sharks and rays? A global meta-analysis. Fish and Fisheries, 16, 300–309.CrossRefGoogle Scholar
  16. Feekings, J.P., O’Neill, F.G., Krag, L.A., Ulrich, C., Veiga-Malta, T. (submitted). An evaluation of European initiatives established to encourage industry-led development of selective fishing gears. Fisheries Management and Ecology.Google Scholar
  17. Fryer, R.J., O’Neill, F.G., Edridge, A. (2016). A meta-analysis of haddock size-selection data. Fish and Fisheries, 17, 358–374. Scholar
  18. Fryer, R.J., Summerbell, K., O’Neill, F.G. (2017). A meta-analysis of vertical stratification in demersal trawl gears. Canadian Journal of Fisheries and Aquatic Sciences, 74, 1243–1250.CrossRefGoogle Scholar
  19. Galbraith, R.D. and Rice, A. after Strange, E.S. (2004). An introduction to commercial fishing gear and methods used in Scotland. Scottish Fisheries Information Pamphlet. No. 25, 2004.Google Scholar
  20. Gan, W.S., Yang, J., Kamakura, T. (2012). A review of parametric acoustic array in air. Applied Acoustics, 73, 1211–1219.CrossRefGoogle Scholar
  21. Gilman, E., Clarke, S., Brothers, N., Alfaro-Shigueto, J., Mandelman, J., Mangel, J., Petersen, S., Piovano, S., Thomson, N., Dalzell, P., Donoso, M., Goren, M., Werner, T. (2008). Shark interactions in pelagic longline fisheries. Marine Policy, 32, 1–18.CrossRefGoogle Scholar
  22. Glass, C.W., Wardle, C.S., Gosden, S.J. (1993). Behavioural studies of the principles underlying mesh penetration by fish. ICES Marine Science Symposia, 196, 92–97.Google Scholar
  23. Graham, N. (2003). By-catch reduction in the brown shrimp, Crangon crangon, fisheries using a rigid separation Nordmore grid (grate). Fisheries Research, 59, 393–407.CrossRefGoogle Scholar
  24. Graham, N. (2010). Technical measures to reduce bycatch and discards in trawl fisheries. In P. He (Ed.), Behavior of marine fishes: Capture processes and conservation challenges. Oxford: Wiley-Blackwell.Google Scholar
  25. Handegard, N.O., Michalsen, K., Tjøstheim, D. (2003). Avoidance behaviour in cod (Gadus morhua) to a bottom-trawling vessel. Aquatic Living Resources, 16, 265–270.CrossRefGoogle Scholar
  26. Hannah, R.W., Lomeli, M.J.M., Jones, S.A. (2015). Tests of artificial light for bycatch reduction in an ocean shrimp (Pandalus jordani) trawl: Strong but opposite effects at the footrope and near the bycatch reduction device, Fisheries Research, 170, 60–67.CrossRefGoogle Scholar
  27. He, P., & Pol, M. (2010). Fish behavior near gillnets: Capture processes and influencing factors. In P. He (Ed.), Behavior of marine fishes: Capture processes and conservation challenges. Oxford: Wiley-Blackwell.CrossRefGoogle Scholar
  28. Holst, R., Revill, A., (2009). A simple statistical method for catch comparison studies. Fisheries Research, 95, 254–259.CrossRefGoogle Scholar
  29. Hreinsson, E., Karlsson, H., Gudmundsson, G., Jonsdottir, H., Thorhallsson, T. (2018). Catching Northern Prawn without benthic contact. ICES WGFTFB 2018 REPORT. ICES CM 2018/EOSG:12.Google Scholar
  30. ICES. (2007). Report of the Workshop on Nephrops Selection (WKNEPHSEL). ICES CM 2007/FTC 1, 49pp.Google Scholar
  31. Ingólfsson, Ó.A., & Jørgensen, T. (2006). Escapement of gadoid fish beneath a commercial bottom trawl: Relevance to the overall trawl selectivity. Fisheries Research, 79, 303–312.CrossRefGoogle Scholar
  32. Isaksen, B. (2013). Fish sampling by shooting a mini trawl into the purse-seine net. Norwegian Institute of Marine Research, Havforskningsnytt nr. 2–2013.Google Scholar
  33. Jones, E.G., Summerbell, K., O’Neill, F.G. (2008). The influence of towing speed and fish density on the behaviour of Haddock in a trawl cod-end. Fisheries Research, 94, 166–174.CrossRefGoogle Scholar
  34. Jordan, L.K. Mandelman, J.W. McComb, D.M. Fordham, S.V., Carlson, J.K., Werner, T.B. (2013). Linking sensory biology and fisheries bycatch reduction in elasmobranch fishes: A review with new directions for research. Conservation Physiology, 1(1).CrossRefGoogle Scholar
  35. Kaimmer, S., Stoner, A.W., (2008). Field investigation of rare-earth metal as a deterrent to spiny dogfish in the Pacific halibut fishery. Fisheries Research, 94, 43–47.CrossRefGoogle Scholar
  36. Karlsen, J.D., Melli, V., Krag, L.A. (2018). The luminous net VISIONET – A guiding swimway to the exit or a stressor? ICES WGFTFB 2018 REPORT. ICES CM 2018/EOSG:12Google Scholar
  37. Kennelly, S.J., & Broadhurst, M.K. (2002). By-catch begone: Changes in the philosophy of fishing technology. Fish and Fisheries, 3(4), 340–355.CrossRefGoogle Scholar
  38. Königson, S., Fjälling, A. & Lunneryd, SG., (2002). Reactions in individual fish to strobe light. Field and aquarium experiments performed on whitefish (Coregonus lavaretus). Hydrobiologia, 483, 39–44.CrossRefGoogle Scholar
  39. Krag, L.A., Herrmann, B., Feekings, J.P., Karlsen, J.D. (2016). Escape panels in trawls – A consistent management tool? Aquatic Living Resources, 29, 306.CrossRefGoogle Scholar
  40. Kynoch, R.J., Edridge, A., O’Neill, F.G. (2012). Catch comparison trials with the Faithlie Cod Avoidance Panel (FCAP). Scottish Marine and Freshwater Science, 3(8).Google Scholar
  41. Laird, A., Cahill, J., Liddell, B. (2016). Kons covered fisheyes BRD trial. Report Northern Prawn Fishery.
  42. Liao, J.C. (2007). A review of fish swimming mechanics and behaviour in altered flows. Philosophical Transactions of the Royal Society, 362, 1973–1993.CrossRefGoogle Scholar
  43. Løkkeborg, S., Fernö, A., Humborstad, O.-B. (2010). Fish behavior in relation to longlines. In P. He (Ed.), Behavior of marine fishes: Capture processes and conservation challenges. Oxford: Wiley-Blackwell.Google Scholar
  44. Løkkeborg, S., Siikavuopio, S.I., Humborstad, O.-B., Utne-Palm, A.C., Ferter, K. (2014). Towards more efficient longline fisheries: Fish feeding behaviour, bait characteristics and development of alternative baits. Reviews in Fish Biology and Fisheries, 24, 985–1003.CrossRefGoogle Scholar
  45. Madsen, N. (2007). Selectivity of fishing gears used in the Baltic Sea cod fishery. Reviews in Fish Biology and Fisheries, 17, 517-544.CrossRefGoogle Scholar
  46. Main, J., & Sangster, G.I. (1981). A study of the fish capture process in a bottom trawl by direct observations from a towed underwater vehicle (Scottish fisheries research report No. 23). Aberdeen: Department of Agriculture and Fisheries for Scotland, 23 pp.Google Scholar
  47. Marçalo, A., Breen, M., Tenningen, M., Onandia, I., Arregi, L., Gonçalves, J.M.S. (this volume). Mitigating slipping related mortality from purse seine fisheries for small pelagic fish: Case studies from European Atlantic waters. In S.S. Uhlmann, C. Ulrich, S.J. Kennelly (Eds.), The European Landing Obligation – Reducing discards in complex multi-species and multi-jurisdictional fisheries. Cham: Springer.Google Scholar
  48. Marchesan, M., Spoto, M., Verginella, M., Ferrero, E.A. (2005). Behaviour effects of atificial light on fish species of commercial interest. Fisheries Research, 73, 171–185.CrossRefGoogle Scholar
  49. Millar, R.B., Broadhurst, M.K., MacBeth, W.G. (2004). Modelling between-haul variability in the size selectivity of trawls. Fisheries Research, 67 171–181.CrossRefGoogle Scholar
  50. Mortensen, L.O., Ulrich, C., Qvist Eliasen, S., Olesen, H.J. (2017). Reducing discards without reducing profit: Free gear choice in a Danish result-based management trial. ICES Journal of Marine Science, 74(5), 1469–1479.Google Scholar
  51. Murray, F., Copland, P., Boulcott, P., Robertson, M., Bailey, N. (2016). Impacts of electrofishing for razor clams (Ensis spp.) on benthic fauna. Fisheries Research, 174, 40–46.CrossRefGoogle Scholar
  52. Nguyen, K.Q., Winger, P.D., Morris, C., Grant, S.M. (2017). Artificial lights improve the catchability of snow crab (Chionoecetes opilio) traps. Aquaculture and Fisheries, 2(3), 124–133.CrossRefGoogle Scholar
  53. O’Connell, C.P., Stroud, E.M., He, P. (2014). The emerging field of electrosensory and semiochemical shark repellents: Mechanisms of detection, overview of past studies, and future directions. Ocean & Coastal Management, 97, 2–11.CrossRefGoogle Scholar
  54. O’Neill, F.G., & Mutch, K. (2017). Selectivity in trawl fishing gears Scottish Marine and Freshwater. Science, 8(1).Google Scholar
  55. O’Neill, F.G., Lines, E.K., Kynoch, R.J., Fryer, R.J., Maguire, S. (2014). A short-term economic assessment of incentivised selective gears. Fisheries Research, 157, 13–23.CrossRefGoogle Scholar
  56. O’Neill, F.G., Summerbell, K., Barros, L. (2018). Some recent trials with illuminated grids. ICES WGFTFB 2018 REPORT. ICES CM 2018/EOSG:12.Google Scholar
  57. Perez Comas, J.A., & Pikitch, E.K. (1994). The predictive power of empirical relationships describing size selectivity, with application to gadoid fish. Fisheries Research, 20, 151–164.CrossRefGoogle Scholar
  58. Piasente, M., Knuckey, I.A., Eayrs, S., McShane, P.E. (2004). In situ examination of the behaviour of fish in response to demersal trawl nets in an Australian trawl fishery. Marine and Freshwater Research, 55, 825–835.CrossRefGoogle Scholar
  59. Polet, H. (2010). Electric senses of fish and their application in marine fisheries. In P. He (Ed.), Behavior of marine fishes: Capture processes and conservation challenges. Oxford: Wiley-Blackwell.Google Scholar
  60. Polet, H., Delanghe, F., Verschoore, R. (2005). On electrical fishing for brown shrimp (Crangon crangon) II. Sea trials Fisheries Research, 72, 13–27.CrossRefGoogle Scholar
  61. Popper, A.N., & Carlson, T.J. (1998). Application of sound and other stimuli to control fish behavior. Transactions of the American Fisheries Society, 127, 673–707.CrossRefGoogle Scholar
  62. Reid, D.G., Calderwood, J., Afonso, P., Fauconnet, L., Pawlowski, L., Plet-Hansen, K.S., Radford, Z., Robert, M., Rochet, M.-J., Ordines, F., Rueda, L., Mortensen, L., Ulrich, C., Vermard, Y. (this volume). The best way to reduce discards is never to catch them in the first place! In S.S. Uhlmann, C. Ulrich, S.J. Kennelly (Eds.), The European Landing Obligation – Reducing discards in complex multi-species and multi-jurisdictional fisheries. Cham: Springer.Google Scholar
  63. Reinhardt, J.F., Weaver, J., Latham, P.J., Dell’Apa, A., Serafy, J.E., Browder, J.A., Christman, M., Foster, D.G., Blankinship, D.R. (2018). Catch rate and at-vessel mortality of circle hooks versus J-hooks in pelagic longline fisheries: A global meta-analysis. Fish and Fisheries, 19, 413–430.CrossRefGoogle Scholar
  64. Rihan, D. (2010). Measures to reduce interactions of marine megafauna with fishing operations. In P. He (Ed.), Behavior of marine fishes: Capture processes and conservation challenges. Oxford: Wiley-Blackwell.Google Scholar
  65. Robbins, W.D., Peddemors, V.M., Kennelly, S.J. (2011). Assessment of permanent magnets and electropositive metals to reduce the line-based capture of Galapagos sharks, Carcharhinus galapagensis. Fisheries Research, 109, 100–106.CrossRefGoogle Scholar
  66. Rose, C., Stoner, A.W., Matteson, K. (2005). Use of high-frequency imaging sonar to observe fish behaviour near baited fishing gear. Fisheries Research, 76, 291–304.CrossRefGoogle Scholar
  67. Rosen, S., & Holst, J.C. (2013). DeepVision in-trawl imaging: Sampling the water column in four dimensions. Fisheries Research, 148, 64–73.CrossRefGoogle Scholar
  68. Ryer, C.H. (2008). A review of flatfish behavior relative to trawls. Fisheries Research, 90(2008), 138–146.CrossRefGoogle Scholar
  69. Ryer, C.H., Rose, C.S., & Iseri, P.J. (2010). Flatfish herding behaviour in response to trawl sweeps: A comparison of diel responses to conventional sweeps and elevated sweeps. Fishery Bulletin, 108, 145–154.Google Scholar
  70. Santos, J., Herrmann, B., Mieske, B., Stepputtis, D., Krumme, U., Nilsson, H., (2016). Reducing flatfish bycatch in roundfish fisheries. Fisheries Research 184, 64–73.CrossRefGoogle Scholar
  71. Shephard, S., Goudey, C.A., Read, A., Kaiser, M.J. (2009). Hydrodredge: Reducing the negative impacts of scallop dredging. Fisheries Research, 95, 206–209.CrossRefGoogle Scholar
  72. Stroud, E.M., O’Connell, C.P., Rice, P.H., Snow, N.H., Barnes, B.B., Elshaer, M.R., Hanson, J.E. (2014). Chemical shark repellent: Myth or fact? The effect of a shark necromone on shark feeding behavior. Ocean & Coastal Management, 97, 50–57.CrossRefGoogle Scholar
  73. Struthers, D.P., Danylchuk, A.J, Wilson, A.D.M., Cooke, S.J., (2015). Action cameras: Bringing aquatic and fisheries research into view. Fisheries, 40(10), 502–512.CrossRefGoogle Scholar
  74. Thomsen, B., Humborstad, O.-B., Furevik, D.M. (2010). Fish pots: Fish behavior, capture processes, and conservation issues. In P. He (Ed.), Behavior of marine fishes: Capture processes and conservation challenges. Oxford: Wiley-Blackwell.Google Scholar
  75. Trenkel, V.M., Handegard, N.O., Weber, T.C. (2016). Observing the ocean interior in support of integrated management. ICES Journal of Marine Science, 73, 1947–1954.CrossRefGoogle Scholar
  76. Utne-Palm, A.C., Breen, M., Løkkeborg, S., Humborstad, O.-B. (2018). Behavioural responses of krill and cod to artificial light in laboratory experiments. PLoS ONE, 13(1), e0190918. Scholar
  77. van Marlen, B., Wiegerinck, J.A.M., van Os-Koomen, E., van Barneveld, E. (2014). Catch comparison of pulse trawls and a tickler chain beam trawl. Fisheries Research, 151, 57–69.CrossRefGoogle Scholar
  78. Wardle, C.S. (1993). Fish behaviour and fishing gear. In T.J. Pitcher (Ed.), Behaviour of teleost fishes (pp. 609–643). London: Chapman & Hall.CrossRefGoogle Scholar
  79. Williams, K., Wilson, C.D., Horne, J.K. (2013). Walleye pollock (Theragra chalcogramma) behavior in midwater trawls. Fisheries Research, 143, 109–118.CrossRefGoogle Scholar
  80. Winger, P.D., Eayrs, S., Glass, C.W. (2010). Fish behavior near bottom trawls. In P. He (Ed.), Behavior of marine fishes: Capture processes and conservation challenges. Oxford: Wiley-Blackwell.Google Scholar
  81. Yan, H.Y., Anraku, K., Babaran, R.P. (2010). Hearing in marine fish and its application in fisheries. In P. He (Ed.), Behavior of marine fishes: Capture processes and conservation challenges. Oxford: Wiley-Blackwell.Google Scholar
  82. Yu, C., Chen, Z., Chen, L., He, P. (2007). The rise and fall of electrical beam trawling for shrimp in the East China Sea: Technology, fishery, and conservation implications. ICES Journal of Marine Science, 64, 1592–1597.CrossRefGoogle Scholar

Copyright information

© The Author(s) 2019

Open Access This chapter is licensed under the terms of the Creative Commons Attribution 4.0 International License (, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license and indicate if changes were made.

The images or other third party material in this chapter are included in the chapter’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the chapter’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.

Authors and Affiliations

  • Finbarr G. O’Neill
    • 1
    Email author
  • Jordan Feekings
    • 1
  • Robert J. Fryer
    • 2
  • Laurence Fauconnet
    • 3
  • Pedro Afonso
    • 3
  1. 1.Technical University of Denmark, National Institute of Aquatic ResourcesHirtshalsDenmark
  2. 2.Marine LaboratoryMarine Scotland ScienceAberdeenUK
  3. 3.Marine and Environmental Sciences Centre and OKEANOS Research UnitUniversidade dos AçoresHortaPortugal

Personalised recommendations