The number of protected areas that restrict or prohibit harvest of wild populations is growing. In general, protected areas are expected to increase the abundance of previously‐harvested species. Whether a protected area achieves this expectation is typically evaluated by assessing trends in abundance after implementation. However, the underlying assumption that harvest has actually ceased is rarely tested directly. Determining whether illegal harvest (poaching) has continued in a protected area is important to planning enforcement and adaptive management. Here, we estimated harvest rates for four kelp forest fish species inside marine protected areas (MPAs) and non‐MPA reference sites in the California Channel Islands, from 2003 (when MPAs were implemented) to 2017. We estimated harvest by fitting a size‐structured population model to survey data. Overall, harvest rates were effectively zero in MPAs but much higher in non‐MPA sites. This indicates successful adherence to MPA regulations, and possible displacement of fishing effort to reference sites. However, some poaching was detected in two MPA sites, highlighting the importance of assessing this quantity. This modeling approach could provide a tool to complement the long‐term management of MPA networks, particularly given the difficulty of acquiring harvest rate data at the spatial scale of individual MPAs.

中文翻译：

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对鱼类种群大小分布的分析证实了在海洋保护区停止捕捞

限制或禁止野生种群采伐的保护区数量在增加。一般而言，保护区有望增加以前收获物种的数量。保护区是否达到了这一期望通常是通过评估实施后的丰度趋势来评估的。但是，几乎没有直接检验基本假设，即收获实际上已经停止。确定在保护区内是否继续进行非法收获（偷猎），对于规划执法和适应性管理很重要。在这里，我们估算了2003年（实施MPAs时）至2017年加利福尼亚海峡群岛海洋保护区（MPA）和非MPA参考点内的四种海带森林鱼的收获率。结构化的人口模型以调查数据。总体而言，MPA的收成率实际上为零，但非MPA的收成率要高得多。这表明成功遵守了MPA法规，并可能将捕捞工作转移到参考地点。但是，在两个MPA站点中发现了一些偷猎事件，突出了评估此数量的重要性。这种建模方法可以提供一种工具来补充MPA网络的长期管理，特别是考虑到难以在单个MPA的空间规模上获取收成率数据的情况。