Gill-net selectivity off the Portuguese western coast

  • Published source details Fonseca P., Martins R., Campos A. & Sobral P. (2005) Gill-net selectivity off the Portuguese western coast. Fisheries Research, 73, 323-339.


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, controlled study in 1994–1995 of eight areas of seabed in the Atlantic Ocean, off Portugal (Fonseca et al. 2005) found that larger mesh size gillnets caught less unwanted non-commercial fish catch compared to smaller mesh sizes. The proportions of non-commercial fish catch typically decreased with increasing mesh size, in both number (90 mm: 0.12, 80 mm: 0.07, 70 mm: 0.10, 60 mm: 0.21, 40 mm: 0.22) and weight (90 mm: 0.04, 80 mm: 0.02, 70 mm: 0.04, 60 mm: 0.11, 40 mm: 0.19). A total of 88 different fish species were caught, of which most were low value or non-commercial (see original paper for individual data for the most caught species). Between April 1994–September 1995, a total of 78 sets of gillnet were deployed (1,155 fishing hours, 24–250 m depth) using up to five different mesh sizes: 90 mm (1995 only), 80 mm, 70 mm, 60 mm and 40 mm. Nets were 60 m long and 3 m deep. Fish catch was sorted by species, and lengths and weights recorded.

    (Summarised by: Chris Barrett)

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