Commercial fishing experiments to assess the survival of haddock and whiting after escape from four sizes of diamond mesh cod-ends

  • Published source details Sangster G.I., Lehmann K. & Breen M. (1996) Commercial fishing experiments to assess the survival of haddock and whiting after escape from four sizes of diamond mesh cod-ends. Fisheries Research, 25, 323-345.


This study is summarised as evidence for the following.

Action Category

Use a larger mesh size

Action Link
Marine Fish Conservation
  1. Use a larger mesh size

    A controlled study in 1993 of bottom fishing grounds in the Atlantic Ocean off Northwest Scotland, UK (Sangster et al. 1996) found that increasing the mesh size of trawl codends did not affect the post-release survival of haddock Melanogrammus aeglefinus and whiting Merlangius merlangus. Post-capture survival rates were not statistically different between codend mesh sizes for haddock (110 mm: 85–89%, 100 mm: 73–83%, 90 mm: 79–82%, 70 mm: 48–67%) and whiting (110 mm: 83–86%, 100 mm: 83–86%, 90 mm: 73–78%, 70 mm: 52–60%). In addition, survival was affected by fish length, with higher survival in larger fish. Trawl codends of 110 mm, 100 mm, 90 mm or 70 mm mesh were deployed one at a time in summer 1993. Covers attached over each codend retained haddock and whiting escaped through the meshes. The escaped fish were put into three cages per mesh size (two for 90 mm mesh) on the seabed, and fed and monitored for 60 d. Length and survival of fish was recorded. Details of number and duration of hauls were not reported.

    (Summarised by: Rosslyn McIntyre)

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