Establishing large networks of fully protected marine protected areas (MPAs) is challenging because of displacement costs for fisheries. The use of partially protected areas is often proposed as an alternative. However, how conservation and fisheries outcomes of MPA networks are mediated through time by the level of protection remains uncertain. Here we use a metapopulation model of a commercially exploited demersal coastal fish to assess conservation and fisheries outcomes of alternative management policies. We compare the temporal performances of nonspatial management, large MPAs, or networks of MPAs in an overfished case study. In addition, we assess how the magnitude of both outcomes is mediated by larval connectivity and level of protection. We distinguish the relative contribution to fisheries outcomes of unprotected areas in between MPAs, and unprotected areas further away, receiving less displaced fishing effort and potential biomass export. We show that spatial management outperforms nonspatial management, that conservation and fisheries outcomes increase with increasing levels of protection, that fisheries outcomes in areas in between MPAs are higher when connected through larval dispersal, and that increases in catch are preceded by a short-term decrease. Our results call for an increase in protection levels to meet both ecological and fisheries management goals.

中文翻译：

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海洋保护区网络的渔业成果：保护水平、连通性和时间问题

由于渔业的迁移成本，建立受全面保护的大型海洋保护区 (MPA) 网络具有挑战性。通常建议使用部分保护区作为替代方案。然而，海洋保护区网络的保护和渔业成果如何随着时间的推移通过保护水平进行调节仍然不确定。在这里，我们使用商业开发的底层沿海鱼类的集合种群模型来评估替代管理政策的保护和渔业结果。我们在过度捕捞的案例研究中比较了非空间管理、大型海洋保护区或海洋保护区网络的时间表现。此外，我们评估了幼虫连接性和保护水平如何调节这两种结果的严重程度。我们区分了海洋保护区之间的未保护区和较远的未保护区（接收较少的流离失所的捕捞作业和潜在的生物质出口）对渔业成果的相对贡献。我们表明，空间管理优于非空间管理，保护和渔业成果随着保护水平的提高而增加，海洋保护区之间区域的渔业成果在通过幼体扩散连接时更高，并且捕捞量增加之前会出现短期下降。我们的结果要求提高保护水平，以实现生态和渔业管理目标。