Data_Sheet_1_Demo-Genetic Approach for the Conservation and Restoration of a Habitat-Forming Octocoral: The Case of Red Coral, Corallium rubrum, in the Réserve Naturelle de Scandola.DOCX

Marine protected areas (MPAs) are one of the most efficient conservation tools to buffer marine biodiversity loss induced by human activities. Beside effective enforcement, an accurate understanding of the eco-evolutionary processes underlying the patterns of biodiversity is needed to reap the benefits of management policies. In this context, integrating population genetics with demographic data, the demo-genetic approach, is particularly relevant to shift from a “species-based pattern” toward an “eco-evolutionary-based processes” conservation. Here, targeting a key species in the Mediterranean coralligenous, the red coral, Corallium rubrum, in an emblematic Mediterranean MPA, the “Réserve Naturelle de Scandola” (France), we applied demo-genetic approaches at two contrasted spatial scales, among populations and within one population, to (i) infer the demographic connectivity among populations in the metapopulation network and (ii) shed new light on the genetic connectivity and on the demographic transitions underlying the dynamics of a near-pristine population. Integrating different spatial and temporal scales, we demonstrated (i) an apparent temporal stability in the pattern of genetic diversity and structure in the MPA in spite of a dramatic demographic decline and (ii) contrasted levels of genetic isolation but substantial demographic connectivity among populations. Focusing on the near-pristine population, we complemented the characterization of red coral demographic connectivity suggesting (iii) temporal variability and (iv) the occurrence of collective dispersal. In addition, we demonstrated (v) contrasted patterns of spatial genetic structure (SGS), depending on the considered stage-class (adults vs. juveniles), in the near-pristine population. This last result points out that the overall SGS resulted from a restricted dispersal of locally produced juveniles (SGS among adults and juveniles) combined to mortality during early life stages (decrease of SGS from juveniles to adults). Demonstrating the occurrence of two management units and the importance of two populations (CAVB and ALE) for the network of connectivity, we made recommendations for the management of the Réserve Naturelle de Scandola. Besides, we contributed to the implementation of scientifically driven restoration protocols in red coral by providing estimates for the size, density, and distances among patches of transplanted colonies.

海洋保护区（Marine Protected Areas, MPAs）是减缓人类活动引发的海洋生物多样性丧失的最高效保护手段之一。除实施有效监管外，还需精准掌握支撑生物多样性格局的生态-进化过程，方能充分发挥管理政策的效用。在此背景下，将种群遗传学与种群统计数据相结合的种群统计-遗传整合方法（demo-genetic approach），对于实现从"基于物种的保护格局"向"基于生态-进化过程的保护"的转变具有重要意义。本研究以地中海标志性海洋保护区——法国斯坎多拉自然保护区（Réserve Naturelle de Scandola）内的地中海珊瑚藻礁群落关键物种红珊瑚（Corallium rubrum）为研究对象，在种群间与单一种群内部两种差异显著的空间尺度上应用种群统计-遗传整合方法，旨在（1）推断集合种群网络中各群体间的种群统计连通性；（2）为解析近原生种群动态背后的遗传连通性与种群统计转变过程提供全新视角。通过整合不同空间与时间尺度的数据，本研究发现：（1）尽管该海洋保护区内的种群统计数量出现大幅下降，但其遗传多样性与遗传结构格局仍呈现出明显的时间稳定性；（2）种群间的遗传隔离水平存在显著差异，但种群统计连通性却较强。针对该近原生种群，本研究进一步补充了红珊瑚种群统计连通性的特征解析，结果表明：（3）种群连通性存在时间变异；（4）存在集体扩散现象。此外，本研究还发现（5）在该近原生种群中，空间遗传结构（Spatial Genetic Structure, SGS）的模式因所研究的生活史阶段（成体与幼体）不同而存在显著差异。这一结果表明，整体空间遗传结构是由本地幼体扩散受限（成体与幼体间均存在空间遗传结构）以及早期生活史阶段的死亡率共同作用形成的——即从幼体到成体，空间遗传结构强度会出现下降。本研究明确了该区域存在两个管理单元，以及两个种群（CAVB与ALE）在连通性网络中的重要价值，并据此为斯坎多拉自然保护区的管理提出了建议。此外，本研究还通过提供移植珊瑚群落斑块的大小、密度及斑块间距离的估算值，为红珊瑚科学修复方案的落地实施提供了支撑。