Non-commercial invertebrate discards in an experimental trammel net fishery

  • Published source details Gonçalves J.M.S., Bentes L., Coelho R., Monteiro P., Ribeiro J., Correia C., Lino P.G. & Erzini K. (2008) Non-commercial invertebrate discards in an experimental trammel net fishery. Fisheries Management and Ecology, 15, 199-210.


This study is summarised as evidence for the following.

Action Category

Use a larger mesh size on trammel nets

Action Link
Subtidal Benthic Invertebrate Conservation
  1. Use a larger mesh size on trammel nets

    A replicated, controlled study in 2001 off the coast of Algarve, southern Portugal, North Atlantic Ocean (Gonçalves et al. 2008) found that using larger mesh sizes in the inner and/or outer panels of trammel nets did not affect the community composition or reduce the abundance of unwanted catch of non-commercial invertebrates (discard). Discard community composition was similar in all six mesh-size configurations tested (data presented as statistical model results and graphical analyses). This was also true for their abundance which ranged from 21 to 29 individuals/1,000 m of net (corresponding to 39–54% of the total catch). Between January and December 2000, six trammel net configurations were tested during 40 fishing trials. Each configuration consisted of a combination of one of two sizes of large-mesh outer panels (600 or 800 mm) and one of three small-mesh inner panels (100, 120, or 140 mm). A total of 150 nets were deployed in groups (30 nets/group). For each group, five nets of each configuration were joined by a footrope (2-m gap between each net). For each configuration, catches were sorted into commercial (fishery target species and commercial bycatch) and unwanted non-commercial species (invertebrate discards), identified and counted. Commercial catch data for each configuration were not reported.

    (Summarised by: Anaëlle Lemasson & Laura Pettit)

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