Evaluation of a by-catch reduction device for glass eel fishing traps

  • Published source details Lopez M.A. & Gisbert E. (2009) Evaluation of a by-catch reduction device for glass eel fishing traps. Fisheries Management and Ecology, 16, 438-447.


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, controlled study in 2006 in a lagoon channel in Alfacs Bay in the Mediterranean Sea, Spain (Lopez & Gisbert 2009) found that eel Anguilla anguilla traps with a modified entrance typically reduced the catches of unwanted fish compared to unmodified conventional traps. Overall, the proportion of unwanted fish (all species) was lower in modified traps (63%) than in conventional traps (37%). For individual species, the proportions of young thinlip mullet Liza ramada and golden grey mullet Liza aurata were also lower in modified traps (thinlip: 4%, grey: 21%) than in conventional traps (thinlip: 96%, grey: 79%). Catches of unwanted common goby Pomatoschistus microps, sand smelt Atherina boyeri, Spanish toothcarp Aphanius iberus and juvenile Senegalese sole Solea senegalensis were also lower in modified than conventional traps (data reported as statistical model results). Catches of unwanted black-striped pipefish Syngnathus abaster, sea bass Dicentrarchus labrax and juvenile gilthead seabream Sparus aurata were similar in each trap design (data reported as statistical model results). In addition, proportions of commercial target eel catches were not significantly different between modified (63%) and conventional (37%) trap designs. Modified and conventional traps were deployed on opposite sides of a channel in 23 trials. All traps were a trapezoid frame covered with small mesh (2 mm) and with a funnel entrance. Modified traps had a rigid square-meshed cylinder at the end of the entrance funnel to prevent unwanted species entering the trap.

    (Summarised by: Leo Clarke)

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