Bycatch species such as skates and rays are for most of them not subject to analytical stock assessment. However, their life history characteristics increased their vulnerability to fisheries. In the English Channel and North Sea area, the three main landed Rajidae species are Raja clavata, Raja brachyura and Raja montagui. The current management measure is a global TAC, common for all Rajidae species. Data to process analytical stock assessment are not available for these species, particularly discards data. A Bayesian multispecies biomass production model, following separately the landings and discards was applied to these stocks. This model provided proxies of reference points (MSY and B_MSY) per species. All stocks were depleted in 1990 and are now rebuilding. However, rebuilding speeds are different within the complex, R. clavata being the fastest and R. brachyura the slowest. Furthermore, the proportion of the discards and landings to biomass differ between species, highlighting species specific fishing strategies. Differences in vulnerabilities within the Rajidae complex might be caused by the variability of life history parameters between species as well as landings and discards pattern differences. This second factor, usually not considered for data limited stock assessment, is particularly relevant for highly discarded chondrichthyans species, and might be considered when choosing new methodology to asses Rajidae stocks.

鳐鱼和鳐鱼等兼捕物种大部分不受分析种群评估的约束。然而，他们的生活史特征增加了他们对渔业的脆弱性。在英吉利海峡和北海地区，三个主要的登陆Rajidae物种是Raja clavata、Raja brachyura和Raja montagui。目前的管理措施是全球 TAC，对所有Rajidae物种通用。无法获得这些物种的处理分析种群评估的数据，尤其是丢弃物数据。贝叶斯多物种生物量生产模型，分别按照上岸量和丢弃量应用于这些种群。该模型提供了参考点的代理（MSY 和 B _MSY) 每个物种。所有库存都在 1990 年枯竭，现在正在重建。然而，复合体内的重建速度不同，R. clavata最快，R. brachyura最慢。此外，丢弃物和上岸物与生物量的比例因物种而异，突出了物种特定的捕捞策略。Rajidae综合体内脆弱性的差异可能是由物种之间生活史参数的可变性以及上岸和丢弃模式差异引起的。这第二个因素通常不用于数据有限的种群评估，它与高度丢弃的软骨鱼类物种特别相关，在选择评估 Rajidae 种群的新方法时可能会考虑。