Institut Sénégalais de Recherche Agricole, ISRA, Centre de Recherche Océanographique de Dakar-Thiaroye, CRODT, Dakar, Sénégal.
IRD, Univ Brest, CNRS, Ifremer, UMR Lemar, Dakar, Sénégal.
PLoS One. 2022 Dec 30;17(12):e0279768. doi: 10.1371/journal.pone.0279768. eCollection 2022.
Fisheries management is an important strategy for ensuring sustainable use of resources. However, in West Africa, in the absence of quality data for many stocks and effective stock assessment models, the cases where this has been truly successful are notable for their rarity. In West Africa, small pelagic fish are of great socio-economic importance, as well as good indicators of fish stressors. Here, historical data (2004-2019) of five small pelagic species (Sardina pilchardus, Ethmalosa fimbriata, Trachurus trecae, Scomber colias and Mugil cephalus) were collected in Senegalese waters. The B/BMSY results showed stocks to be collapsed (B/BMSY = 0.13 and 0.1 for M. cephalus and S. pilchardus, respectively) and heavily overfished (B/BMSY = 0.24; E. fimbriata). Only S. colias and T. trecae stock were considered to be in good condition (B/BMSY = 1.7 and 1.4 respectively). The Lc/Lc_opt ratio was ≤ 1 for E. fimbriata and M. cephalus, suggesting that the individuals caught for these species were too small. To reverse these bad stock statuses, catching individuals at Lc_opt, 25, 21, 43 and 18 cm for S. colias, E. fimbriata, M. cephalus and S. pilchardus, respectively should be a natural guarantee against recruitment failure and allow individuals to ensure the long-term survival of populations, in a context of data poor fisheries. In conclusion, this study shows that, despite limitations, the LBB model can provides indicators of stock status for species to encourage management measures, especially in data poor countries. It is hoped that these results can help to better assess many stocks currently considered too data poor to be assessed or at least encourage data collection effort on stocks discerned as in bad or critical status.
渔业管理是确保资源可持续利用的重要策略。然而，在西非，由于许多种群缺乏高质量的数据和有效的种群评估模型，真正成功的例子很少见。在西非，小型洄游鱼类具有重要的社会经济意义，也是鱼类压力的良好指标。在这里，收集了塞内加尔海域的五种小型洄游鱼类（沙丁鱼、鲱鱼、金枪鱼、鲳鱼和鲻鱼）的历史数据（2004-2019 年）。B/BMSY 结果表明，这些种群已经崩溃（B/BMSY 分别为 0.13 和 0.1 的鲻鱼和沙丁鱼），并且过度捕捞（B/BMSY 分别为 0.24；E. fimbriata）。只有 S. colias 和 T. trecae 的种群被认为处于良好状态（B/BMSY 分别为 1.7 和 1.4）。E. fimbriata 和 M. cephalus 的 Lc/Lc_opt 比值均≤1，表明这些物种被捕捞的个体太小。为了扭转这些不良的种群状况，在数据匮乏的渔业环境下，应该在 Lc_opt 处捕捞 S. colias、E. fimbriata、M. cephalus 和 S. pilchardus 的个体，分别为 25、21、43 和 18 厘米，这是防止补充失败和确保种群长期生存的自然保证。总之，本研究表明，尽管存在局限性，LBB 模型可以为物种提供种群状况的指标，以鼓励管理措施，特别是在数据匮乏的国家。希望这些结果能够帮助更好地评估许多目前被认为数据不足而无法评估的种群，或者至少鼓励对被认为处于不良或危急状态的种群进行数据收集。
