Data from: Size, age, and habitat determine effectiveness of Palau's Marine Protected Areas

Palau has a rich heritage of conservation that has evolved from the traditional moratoria on fishing, or "bul", to more western Marine Protected Areas (MPAs), while still retaining elements of customary management and tenure. In 2003, the Palau Protected Areas Network (PAN) was created to conserve Palau's unique biodiversity and culture, and is the country's mechanism for achieving the goals of the Micronesia Challenge (MC), an initiative to conserve ?30% of near-shore marine resources within the region by 2020. The PAN comprises a network of numerous MPAs within Palau that vary in age, size, level of management, and habitat, which provide an excellent opportunity to test hypotheses concerning MPA design and function using multiple discreet sampling units. Our sampling design provided a robust space for time comparison to evaluate the relative influence of potential drivers of MPA efficacy. Our results showed that no-take MPAs had, on average, nearly twice the biomass of resource fishes (i.e. those important commercially, culturally, or for subsistence) compared to nearby unprotected areas. Biomass of non-resource fishes showed no differences between no-take areas and areas open to fishing. The most striking difference between no-take MPAs and unprotected areas was the more than 5-fold greater biomass of piscivorous fishes in the MPAs compared to fished areas. The most important determinates of no-take MPA success in conserving resource fish biomass were MPA size and years of protection. Habitat and distance from shore had little effect on resource fish biomass. The extensive network of MPAs in Palau likely provides important conservation and tourism benefits to the Republic, and may also provide fisheries benefits by protecting spawning aggregation sites, and potentially through adult spillover.帕劳拥有深厚的保护传承历史，其保护体系从传统的捕鱼禁捕习俗（即"bul"）逐步发展为更具西方范式的海洋保护区（Marine Protected Areas, MPAs），同时仍保留了传统管理与权属制度的核心要素。2003年，帕劳保护区网络（Palau Protected Areas Network, PAN）正式成立，旨在保护帕劳独特的生物多样性与文化遗产，同时作为该国落实密克罗尼西亚挑战（Micronesia Challenge, MC）目标的实施机制——该倡议旨在2020年前保护区域内30%的近岸海洋资源。该保护区网络由帕劳境内诸多海洋保护区构成，这些保护区在设立年限、面积、管理等级与栖息生境等维度均存在差异，为依托多个独立采样单元验证海洋保护区设计与功能相关假说提供了绝佳的研究契机。本研究的采样设计构建了严谨的空间替代时间对照框架，以评估影响海洋保护区效能的各类潜在驱动因素的相对权重。研究结果显示：禁捕型海洋保护区内兼具经济、文化或生计价值的资源鱼类生物量平均可达邻近未保护区域的近两倍。而非资源鱼类的生物量在禁捕区域与开放捕捞区域之间并无显著差异。最引人注目的差异在于：禁捕型海洋保护区内的肉食性鱼类（piscivorous fishes）生物量较捕捞区域高出五倍以上。影响禁捕型海洋保护区保护资源鱼类生物量成效的最关键因素为保护区面积与保护时长，栖息生境与离岸距离对资源鱼类生物量的影响则相对微弱。帕劳这套覆盖广泛的海洋保护区网络，不仅为帕劳共和国带来了重要的生态保护与旅游收益，同时也通过保护鱼类产卵聚群位点，以及可能通过成鱼溢出效应，为当地渔业发展提供了助力。