Blacktip reef sharks, Carcharhinus melanopterus, have high genetic structure and varying demographic histories in their Indo-Pacific range

For free-swimming marine species like sharks, only population genetics and demographic history analyses can be used to assess population health/status as baseline population numbers are usually unknown. We investigated the population genetics of blacktip reef sharks, Carcharhinus melanopterus; one of the most abundant reef-associated sharks and the apex predator of many shallow water reefs of the Indian and Pacific Oceans. Our sampling includes 4 widely separated locations in the Indo-Pacific and 11 islands in French Polynesia with different levels of coastal development. Four-teen microsatellite loci were analysed for samples from all locations and two mitochondrial DNA fragments, the control region and cytochrome b, were examined for 10 locations. For microsatellites, genetic diversity is higher for the locations in the large open systems of the Red Sea and Australia than for the fragmented habitat of the smaller islands of French Polynesia. Strong significant structure was found for ...对于鲨鱼这类自由游动的海洋物种而言，由于基线种群数量通常未知，仅能通过种群遗传学与种群历史动态分析来评估其种群健康状况。本研究针对黑鳍礁鲨（*Carcharhinus melanopterus*）开展种群遗传学分析，该物种是印度-太平洋海域众多浅海礁区中数量最为丰富的礁栖鲨鱼之一，同时也是多数浅海礁区的顶级捕食者。本次采样覆盖印度洋-太平洋区域4个相距甚远的采样点，以及法属波利尼西亚的11个沿海开发程度各异的岛屿。所有采样点的样本均被分析了14个微卫星位点（microsatellite loci）；针对其中10个采样点的样本，还额外检测了两段线粒体DNA（mitochondrial DNA）片段：控制区（control region）与细胞色素b（cytochrome b）。针对微卫星位点的分析结果显示，红海与澳大利亚这类大型开放海域的采样点，其遗传多样性高于法属波利尼西亚小型岛屿所在的破碎化栖息环境。研究发现了显著的强遗传结构……