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，其保护实践从传统的捕鱼禁限令“bul”，逐步发展为更具西方范式的海洋保护区（Marine Protected Areas, MPAs），同时仍保留了习惯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）正式设立，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）目标的核心机制——该倡议旨在至2020年保护区域内30%的近岸海洋资源。帕劳保护区网络由境内众多海洋保护区组成，这些保护区在设立年限、面积规模、管理等级与栖息生境方面均存在显著差异，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保护效能的各类潜在驱动因素的相对作用强度。研究结果表明：禁捕型海洋保护区内的资源鱼类（resource fishes，即具有商业、文化或生计价值的鱼类）生物量平均近乎是邻近未保护区域的两倍。非资源鱼类的生物量在禁捕区域与开放捕鱼区域之间未呈现显著差异。禁捕型海洋保护区与未保护区域最显著的差异在于：保护区内的肉食性鱼类（piscivorous fishes）生物量较捕捞区域高出5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年限，栖息生境与离岸距离对资源鱼类生物量的影响微乎其微。帕劳广布的海洋保护区网络大概率为帕劳共和国带来了重要的生态保护与旅游收益，同时通过保护鱼类产卵集结地，以及可能通过成鱼溢出效应，为当地渔业发展提供了潜在助力。