Starting from the year 2000, the European Union planned to establish the use of a selective trawl in brown shrimp (Crangon crangon) fisheries. In fact, the brown shrimp is caught by a bottom trawl equipped with stretched 20 mm exempted meshing in estuary areas where the nurseries of flat fish and gadidae are located. For Vilaine's estuary, Dupouy et al (1997) estimated at about 1 tonne of flat fish and one tonne of gadidae the loss in equivalent fish of marketable size, per landed tonne of brown shrimp. In this document, the authors introduce improvements resulting from the use of selective trawls developed in France (Asselin and Devismes trawls), and they show by what means the selectivity of these trawls can be improved further. |