Study

The use of square mesh codends in the Icelandic shrimp (Pandalus borealis) fishery

  • Published source details Thorsteinsson G. (1992) The use of square mesh codends in the Icelandic shrimp (Pandalus borealis) fishery. Fisheries Research, 13, 255-266.

Actions

This study is summarised as evidence for the following.

Action Category

Use a square mesh instead of a diamond mesh codend in a trawl net

Action Link
Marine Fish Conservation
  1. Use a square mesh instead of a diamond mesh codend in a trawl net

    A replicated, paired, controlled study in 1988–1990 of a bottom fishing ground in the Greenland Sea, north Iceland (Thorsteinsson 1992) reported that shrimp trawl nets with square mesh codends caught less small, unwanted fish than conventional diamond mesh codends. Data were not statistically tested. In two of two comparisons, catch rates of fish aged <1 year were lower in square mesh than diamond mesh codends for Atlantic cod Gadus morhua (square: 2–8 fish/ha, diamond: 6–130 fish/ha) and whiting Merlangius merlangus (square: 4–376 fish/ha, diamond: 27–2,472 fish/ha), and in one case for haddock Melanogrammus aeglefinus (square: 0–457 fish/ha, diamond: 0–1,245 fish/ha). Catches of one- and two-year-old fish were low but were typically lower in square mesh codends (see paper for data). Overall capelin Mallotus villosus catch rates (all ages) were lower in square mesh codends in two of two cases (square: 133–284, diamond: 842–1,104 fish/ha). Target shrimp Pandalus borealis catches were lower in square than diamond mesh codends in three of three comparisons. In 1988 and 1990, catches were compared between square mesh codends (36–37 mm) and conventional diamond mesh codends (36–40 mm) in 11 deployments of the two trawl net types towed side by side for 1 h.

    (Summarised by: Leo Clarke)

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