Abstract:
The coastline of Sub-Saharan Africa hosts highly diverse fish communities of great conservation value, which are also key resources for local livelihoods. However, many costal ecosystems are threatened by overexploitation and their conservation state is frequently unknown due to their vast spatial extent and limited monitoring budgets. Here, we evaluated the potential of citizen science-based eDNA surveys to alleviate such chronic data deficiencies and assessed fish communities in Mozambique using two 12S metabarcoding primer sets. Samples were either collected by scientific personnel or trained community members and results from the two metabarcoding primers were combined using a new data merging approach. Irrespective of the background of sampling personnel, a high average fish species richness was recorded (38 ± 20 OTUs per sample). Individual sections of the coastline largely differed in the occurrence of threatened and commercially important species, highlighting the need for regionally differentiated management strategies. A detailed comparison of the two applied primer sets revealed an important trade-off in primer choice with MiFish primers amplifying a higher number of species but Riaz primers performing better in the detection of threatened fish species. This trade-off could be partly resolved by applying our new data-merging approach, which was especially designed to increase the robustness of multiprimer assessments in regions with poor reference libraries. Overall, our study provides encouraging results but also highlights that eDNA-based monitoring will require further improvements of, for example, reference databases and local analytical infrastructure to facilitate routine applications in Sub-Saharan Africa.
摘要:
撒哈拉以南非洲的海岸线拥有高度多样化的鱼类群落,具有巨大的保护价值,这也是当地生计的关键资源。然而,许多沿海生态系统受到过度开发的威胁,由于其广阔的空间范围和有限的监测预算,其保护状态往往是未知的。这里,我们评估了基于公民科学的eDNA调查在缓解此类慢性数据缺陷方面的潜力,并使用两套12S元碳编码引物对莫桑比克的鱼类群落进行了评估.由科学人员或经过培训的社区成员收集样品,并使用新的数据合并方法将两种元编码引物的结果合并。无论抽样人员的背景如何,记录到较高的平均鱼类物种丰富度(每个样本38±20个OTU)。海岸线的各个部分在受威胁和商业上重要的物种的发生方面大不相同,强调区域差异化管理策略的必要性。对两个应用的引物组进行的详细比较表明,在引物选择方面存在重要的权衡,MiFish引物扩增了更多的物种,而Riaz引物在检测受威胁的鱼类物种方面表现更好。这种权衡可以通过应用我们新的数据合并方法来部分解决,这是特别设计的,以提高多引物评估的稳健性,在地区的参考图书馆差。总的来说,我们的研究提供了令人鼓舞的结果,但也强调了基于eDNA的监测将需要进一步改进,例如,参考数据库和当地分析基础设施,以促进撒哈拉以南非洲的常规应用。