2025-06-26 サセックス大学
＜関連情報＞
- https://www.sussex.ac.uk/research/full-news-list?id=68481
- https://onlinelibrary.wiley.com/doi/10.1002/edn3.70131
- https://peerj.com/articles/17091/
時事問題：動的な潮汐生息地における相対的存在量モニタリングのための環境DNAの利用を検討する Current Affairs: Examining the Use of Environmental DNA for Relative Abundance Monitoring in a Dynamic Tidal Habitat
Alice J. Clark, Valentina Scarponi, Tim Cane, Francesco S. Marzano, Nathan R. Geraldi, Reuben J. Shipway, Ian W. Hendy, Mika Peck
Environmental DNA Published: 28 May 2025
DOI:https://doi.org/10.1002/edn3.70131
ABSTRACT
Assessing the abundance and spatiotemporal distribution of fish species is crucial for informing sustainable fishing practices and developing effective conservation management plans. Recently, environmental DNA (eDNA) has emerged as a promising tool for estimating not only marine species richness but also species abundance, with several studies demonstrating a positive correlation between eDNA concentration and species abundance. Consequently, eDNA surveys not only enhance the monitoring of species requiring conservation attention but may also serve as a method to quantify relative abundance, a critical indicator of ecosystem health. This study investigates the feasibility of using eDNA metabarcoding to estimate relative abundance of marine species in a tidal environment, using Sussex Bay, UK, as a case study. We compared eDNA relative abundance indices, estimated by the metabarcoding method, using two different primer pairs and found strong positive correlations between the results from each primer. Additionally, we evaluated the relationship between relative abundance estimates derived from eDNA metabarcoding index and those obtained from Baited Remote Underwater Video (BRUV) counts. Out of 14 species, only one significant positive correlation was found between eDNA index and BRUV counts. The BRUV surveys detected fewer species overall compared to eDNA, leading to a higher number of zero counts for several species, which may explain the lack of statistically significant relationships. This indicates that eDNA index and BRUV counts do not strongly correlate in dynamic marine environments, highlighting the differences between these survey methods. This study also estimated that eDNA can be detected at least 2–8 km from its assumed source in a marine tidal environment, with an average minimum travel speed of 1.8 km/h. Our findings illustrate the effectiveness of eDNA metabarcoding as a nondestructive biomonitoring method, while also highlighting its limitations as well as the challenges in comparing relative abundances of different methods in tidal environments.
海洋生態系モニタリングにおける餌付き遠隔水中ビデオ（BRUV）と環境DNA（eDNA）の費用対効果分析 Cost-effort analysis of Baited Remote Underwater Video (BRUV) and environmental DNA (eDNA) in monitoring marine ecological communities
Alice J. Clark, Sophie R. Atkinson, Valentina Scarponi, Tim Cane, Nathan R. Geraldi, Ian W. Hendy, J. Reuben Shipway, Mika Peck
PeerJ Published: April 30, 2024
DOI:https://doi.org/10.7717/peerj.17091
Abstract
Monitoring the diversity and distribution of species in an ecosystem is essential to assess the success of restoration strategies. Implementing biomonitoring methods, which provide a comprehensive assessment of species diversity and mitigate biases in data collection, holds significant importance in biodiversity research. Additionally, ensuring that these methods are cost-efficient and require minimal effort is crucial for effective environmental monitoring. In this study we compare the efficiency of species detection, the cost and the effort of two non-destructive sampling techniques: Baited Remote Underwater Video (BRUV) and environmental DNA (eDNA) metabarcoding to survey marine vertebrate species. Comparisons were conducted along the Sussex coast upon the introduction of the Nearshore Trawling Byelaw. This Byelaw aims to boost the recovery of the dense kelp beds and the associated biodiversity that existed in the 1980s. We show that overall BRUV surveys are more affordable than eDNA, however, eDNA detects almost three times as many species as BRUV. eDNA and BRUV surveys are comparable in terms of effort required for each method, unless eDNA analysis is carried out externally, in which case eDNA requires less effort for the lead researchers. Furthermore, we show that increased eDNA replication yields more informative results on community structure. We found that using both methods in conjunction provides a more complete view of biodiversity, with BRUV data supplementing eDNA monitoring by recording species missed by eDNA and by providing additional environmental and life history metrics. The results from this study will serve as a baseline of the marine vertebrate community in Sussex Bay allowing future biodiversity monitoring research projects to understand community structure as the ecosystem recovers following the removal of trawling fishing pressure. Although this study was regional, the findings presented herein have relevance to marine biodiversity and conservation monitoring programs around the globe.
