Commercial bycatch species and their exploitation pattern in the Mediterranean trawl fishery are little studied. The present work examines the overall size-selection pattern, both regarding the trawl in the sea and the fisher onboard the vessel, for seven commercial bycatch species using different codends. The applied selection model predicted the escape, discard, and landing probability for each species simultaneously, a useful method for providing information important for fisheries management under the ecosystem approach. Among the studied codends, the 40-mm diamond mesh codend, still in use in non-EU Mediterranean fleets, was found unsuitable for the stocks in all cases. The 40-mm square mesh codend (40S) was found appropriate for blue whiting (Micromesistius poutassou), comber (Serranus cabrilla), and bogue (Boops boops) sustainability. The 50-mm diamond mesh codend (50D) was more suitable than the square mesh codend only for the spotted flounder (Citharus linguatula). Both the 40S and the 50D codends were appropriate for picarel (Spicara smaris), whereas none ensured sustainable exploitation for the blackbelly rosefish (Helicolenus dactylopterus), and the streaked gurnard (Chelidonichthys lastoviza). The results are discussed in relation to juvenile protection, discard mitigation, and fisher selection behaviour, important factors for the sustainability of stocks and fisheries in the Common Fishery Policy for the Mediterranean Sea.

中文翻译：

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多物种地中海底拖网渔业的逃逸、丢弃和登陆概率

对地中海拖网渔业中的商业兼捕物种及其开发模式的研究很少。目前的工作检查了使用不同密码的七种商业兼捕物种的总体尺寸选择模式，包括海上拖网和船上渔民。应用的选择模型同时预测了每个物种的逃逸、丢弃和登陆概率，这是在生态系统方法下为渔业管理提供重要信息的有用方法。在所研究的编码器中，40 毫米菱形网格编码器仍在非欧盟地中海船队中使用，但在所有情况下都不适用于库存。发现 40 毫米方形网格编码 (40S) 适用于蓝鳕 (Micromesistius poutassou)、精梳机 (Serranus cabrilla) 和博格 (Boops boops) 的可持续性。50-mm 菱形网格编码器 (50D) 比方形网格编码器仅适用于斑点比目鱼 (Citharus linguatula)。40S 和 50D codends 都适用于 picarel (Spicara smaris)，而没有一个确保对黑腹蔷薇 (Helicolenus dactylopterus) 和条纹鲽 (Chelidonichthys lastoviza) 的可持续开发。讨论了与少年保护、减少丢弃物和渔民选择行为有关的结果，这些都是地中海共同渔业政策中种群和渔业可持续性的重要因素。而没有一个确保对黑腹玫瑰鱼（Helicolenus dactylopterus）和条纹鲂鱼（Chelidonichthys lastoviza）的可持续开发。讨论了与少年保护、减少丢弃物和渔民选择行为有关的结果，这些都是地中海共同渔业政策中种群和渔业可持续性的重要因素。而没有一个确保对黑腹玫瑰鱼（Helicolenus dactylopterus）和条纹鲂鱼（Chelidonichthys lastoviza）的可持续开发。讨论了与少年保护、减少丢弃物和渔民选择行为有关的结果，这些都是地中海共同渔业政策中种群和渔业可持续性的重要因素。