Size selective capture of Atlantic cod (Gadus morhua) in floating pots

  • Published source details Ovegård M., Königson S., Persson A. & Lunneryd S.G. (2011) Size selective capture of Atlantic cod (Gadus morhua) in floating pots. Fisheries Research, 107, 239-244.


This study is summarised as evidence for the following.

Action Category

Modify fishing trap/pot configuration

Action Link
Marine Fish Conservation
  1. Modify fishing trap/pot configuration

    A replicated, randomized, paired, controlled study in 2009–2010 in shallow coastal waters of the Bay of Hanö in the Baltic Sea, Sweden (Ovegård et al. 2011) found that floating traps (pots) modified with square mesh escape windows allowed the escape of high proportions of undersized Atlantic cod Gadus morhua, and size-selectivity increased with increasing window mesh size. Pots with square mesh escape windows allowed the escape of over 90% of cod under the minimum landing size of 38 cm (data presented graphically). The length at which cod had a 50% chance of escaping increased with increasing mesh size of the escape window (40 mm: 32 cm, 45 mm: 38 cm, 50 mm: 40 cm). Data were collected in April 2009–January 2010 from a commercial fishing vessel. A total of 54 paired deployments were done of four pots with identical escape window mesh size (three different sizes: 40 mm, 45 mm and 50 mm), and four without windows, set randomly along a line (string). All pots were baited with Baltic herring Clupea harengus and soak-time was 1–14 days. See original paper for full gear specifications.

    (Summarised by: Chris Barrett)

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