The reduction of cod discards by inserting 300mm diamond mesh netting in the forward sections of a trawl gear

  • Published source details Campbell R., Harcus T., Weirman D., Fryer R.J., Kynoch R.J. & O’Neill F.G. (2010) The reduction of cod discards by inserting 300mm diamond mesh netting in the forward sections of a trawl gear. Fisheries Research, 102, 221-226.


This study is summarised as evidence for the following.

Action Category

Fit mesh escape panels/windows to a trawl net

Action Link
Marine Fish Conservation
  1. Fit mesh escape panels/windows to a trawl net

    A replicated, paired, controlled study in 2008 of a seabed area in the North Sea, off Scotland, UK (Campbell et al. 2010) found that fitting escape panels of large diamond mesh in the forward sections of a bottom trawl net reduced catches of unwanted Atlantic cod Gadus morhua, compared to trawl nets with sections of standard mesh size. Fewer cod were caught in the trawl net with escape panels than without (with: 3–511 kg/tow, standard mesh: 7–1,019 kg/tow), was dependent on length (45% fewer cod at 35 cm and 19% fewer cod at 80 cm), and the reduction significant for cod up to 78 cm in length. In addition, catches of smaller monkfish Lophius piscatorius and megrim Lepidorhombus whiffiagonis were reduced, by 37% at 37 cm and 43% at all lengths, respectively (with: 0–261 kg, without: 0–319 kg), and were similar for haddock Melanogrammus aeglefinus and whiting Merlangius merlangus (with: 20–927 kg, without: 17–804 kg). Data were collected in October-November 2008 from 30 paired trawl deployments on a commercial twin rig trawler on bottom fishing grounds 65 miles west of Shetland. The vessel towed identical nets apart from the test net having two panels in the top section and one in the bottom and wings made from 300 mm diamond mesh netting instead of the standard 160 mm diamond mesh (‘Orkney Gear’ - see paper for specifications). Catches from each net were sorted by species and weighed. Lengths of selected species were measured.

    (Summarised by: Natasha Taylor)

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