Size selectivity of sole gill nets fished in the North Sea

  • Published source details Madsen N., Holst R., Wileman D. & Moth-Poulsen T. (1999) Size selectivity of sole gill nets fished in the North Sea. Fisheries Research, 44, 59-73.


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 replicated, randomized study in 1995 of bottom fishing grounds in the central North Sea, north Europe (Madsen et al. 1999) found that increasing the mesh size in a gillnet caught fewer unwanted small fish compared to smaller mesh sizes. For all three species, average catch length increased and catch numbers of undersized fish decreased between the largest (118 mm) and smallest (81 cm) mesh sizes: for sole Solea solea (length, largest mm: 31 cm, smallest: 27 cm; undersized, largest: 26 fish, smallest: 407 fish), plaice Pleuronectes platessa (length, largest mm: 40 cm, smallest: 24 cm; undersized, largest: 87 fish, smallest: 274 fish) and cod Gadus morhua (length, largest mm: 41 cm, smallest: 27 cm; undersized, largest: 20 fish, smallest: 94 fish). Fishing took place during May and June 1995 with nets deployed overnight. A total of 24 gillnet deployments containing 10 fleets of seven nets, each with a different mesh size (118 mm, 113 mm, 105 mm, 99 mm, 92 mm, 86 mm and 81 mm) were set overnight. The order of the nets in a fleet was randomized. Catch was sorted and fish lengths recorded.

    (Summarised by: Chris Barrett)

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