Information on catch and effort of recreational angling in mixed-use fisheries (co-exploited by commercial and recreational fishers) is often scarce, preventing the application of data-rich stock assessments typically performed for industrialised commercial fisheries. This study shows how data-poor stock assessment methods developed for marine fisheries, particularly a model class labelled as “catch-only” models (COMs), offer a possible solution. As a case study, COMs are used to assess a northern pike Esox lucius L. stock around the German Baltic island of Rügen. Multiple COMs were fitted to a time series of total pike removals, and their outputs were used as explanatory variables in ensemble models. The stock was found to be fully exploited and currently declining. This study highlights the potential for using COMs to determine status of previously unassessed coastal and freshwater stocks facing recreational fishing pressure and demonstrates how incorporating recreational removals is crucial for achieving reliable insights into the status of mixed-use stocks.

中文翻译：

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商业和休闲渔业共同捕捞的鱼类资源缺乏数据评估：在波罗的海西部的梭子鱼的应用

关于混合用途渔业（由商业和休闲渔民共同开发）中休闲垂钓的渔获量和努力的信息通常很少，这阻碍了通常对工业化商业渔业进行的数据丰富的种群评估的应用。这项研究显示了为海洋渔业开发的缺乏数据的种群评估方法，特别是标记为“仅捕捞”模型 (COM) 的模型类，如何提供可能的解决方案。作为一个案例研究，COM 用于评估北部梭子鱼Esox lucius德国波罗的海吕根岛周围的 L. 库存。将多个 COM 拟合到总梭子鱼去除的时间序列中，并将它们的输出用作集合模型中的解释变量。该库存被发现已被充分开发，目前正在下降。本研究强调了使用 COM 来确定以前未经评估的沿海和淡水种群面临休闲捕鱼压力的状态的潜力，并展示了如何结合休闲清除对于获得对混合用途种群状态的可靠见解至关重要。