Effective fisheries management is crucial for the sustainable use of fishery resources, increasing relying on stock assessments. The Megalaspis cordyla an economically important fish species in Pakistan, require an accurate assessment of its current biomass to take effective management strategies. This study utilized stock assessment techniques, including the Catch-Based Monte Carlo Maximum Sustainable Yield (CMSY), length-based Bayesian Biomass (LBB), Just Another Bayesian Biomass Assessment (JABBA), and ARIMA models. While CMSY, BSM, JABBA, ARIMA rely on annual catch-effort data, while LBB analyzes length-frequency data along with resilience inputs. An analysis of 15 years of catch data (2007-2021), and 1,442 length-frequency data from Pakistani waters revealed that the fishery is overfished both in terms of exploitation and biomass (LBB at F/M = 1.6, B/BMSY = 0.76 and B/B0 = 0.27). The CMSY method estimated biological reference points as r = 0.53, k = 231, and a maximum sustainable yield (MSY) of 3.06. In comparison, the BSM provide values of r =0.03, k =271, MSY = 2.56. The JABBA model estimated MSY of 3.637, with a biomass to MSY2021 (B2021/BMSY) of 0.68 and F2021/FMSY of 1.56, indicating excessive exploitation. The projected biomass ratio (B2021/BMSY) of 0.798, is<1, confirms overexploitation. Additionally, the ARIMA (2, 0, 1) model, demonstrated the lowest mean square error, predicts a significant upward trend in fish catches in the near future. The findings across all models consistently indicate that the M. cordyla fishery is overfished, with current catches exceeding sustainable limits. Biological reference points from CMSY, JABBA, and LBB models, all below 1.0, underscore the unsustainable of the fishery. If current trend continues, the fishery faces a substantial risk of collapse. To mitigate this, immediate management measures should be implemented to promote the sustainable utilization of this critical fishery resource in Pakistan.

中文翻译：

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评估阿拉伯海北部 Megalaspis cordyla 的种群状况：可持续渔业管理的多模式方法


有效的渔业管理对于渔业资源的可持续利用至关重要，这增加了对种群评估的依赖。Megalaspis cordyla 是巴基斯坦具有重要经济意义的鱼类，需要准确评估其当前的生物量以采取有效的管理策略。本研究利用了种群评估技术，包括基于渔获量的蒙特卡洛最大可持续产量 （CMSY）、基于长度的贝叶斯生物量 （LBB）、Just Another 贝叶斯生物量评估 （JABBA） 和 ARIMA 模型。CMSY、BSM、JABBA、ARIMA 依赖于年度捕获努力数据，而 LBB 分析长度频率数据以及弹性输入。对 15 年渔获数据（2007-2021 年）和来自巴基斯坦水域的 1,442 个长度频率数据的分析表明，该渔业在开发量和生物量方面都被过度捕捞（LBB 在 F/M = 1.6、B/BMSY = 0.76 和 B/B0 = 0.27）。CMSY 方法估计的生物参考点为 r = 0.53，k = 231，最大可持续产量 （MSY） 为 3.06。相比之下，BSM 提供的值为 r =0.03、k =271、MSY = 2.56。JABBA 模型估计 MSY 为 3.637，生物量与MSY2021 （B2021/BMSY） 为 0.68，F2021/FMSY 为 1.56，表明过度开采。预计生物量比 （B2021/BMSY） 为 0.798，即 <1，证实了过度开发。此外，ARIMA （2， 0， 1） 模型显示出最低的均方误差，预测在不久的将来渔获量将呈显著上升趋势。所有模型的调查结果一致表明，M. cordyla 渔业被过度捕捞，目前的渔获量超过了可持续限度。来自 CMSY、JABBA 和 LBB 模型的生物参考点均低于 1.0，这凸显了渔业的不可持续性。 如果目前的趋势继续下去，渔业将面临巨大的崩溃风险。为了缓解这种情况，应立即实施管理措施，以促进巴基斯坦这一重要渔业资源的可持续利用。