Assessments of many West African fish stocks rely on fishery dependent catch and effort data. Typically, these treat the catch data as error free and some assume that fishing power does not change over time. To address these issues we develop a fleet based surplus production model that accounts for increases in fishing power. It allows errors both in effort and catch data so avoiding the assumption that catch data are exact. Mean annual fleet fishing power increase can be estimated when data from multiple fleets are available provided it can be specified for at least one fleet. The model is tested using simulated data and then applied to western stocks of anchovy (Engraulis encrasicolus) and bonga shad (Ethmalosa fimbriata) in the Fishery Committee for the Eastern Central Atlantic (CECAF) area. Both stocks appear to be over-exploited and near to collapse. Corrections for fishing power are important in the anchovy assessment and help to explain conflicting trends in the data. Uncertainty in the assessments is explored with a range of sensitivity tests.

对许多西非鱼类资源的评估依赖于依赖渔业的捕捞量和努力量数据。通常，他们将捕获数据视为没有错误，有些人假设捕捞能力不会随时间变化。为了解决这些问题，我们开发了一个基于船队的剩余生产模型，该模型考虑了捕鱼能力的增加。它允许在努力和捕获数据中出现错误，从而避免假设捕获数据是准确的。如果可以为至少一个船队指定数据，则可以在可以获得来自多个船队的数据时估计平均每年船队捕捞能力的增加。该模型使用模拟数据进行测试，然后应用于西部鳀鱼（Engraulis encrasicolus）和鲱鱼（Ethmalosa fimbriata）种群。) 中东部大西洋渔业委员会 (CECAF) 地区。两只股票似乎都被过度开发并接近崩溃。捕捞能力的修正在鳀鱼评估中很重要，有助于解释数据中的相互矛盾的趋势。评估中的不确定性是通过一系列敏感性测试来探索的。