March 2024
Before launching seagrass restoration trials in Mauritius, the team conducted an eDNA-based biodiversity survey's in 2023 to establish a baseline of species living in natural and sandy habitats. The findings revealed far greater diversity in seagrass meadows and will serve as a benchmark to measure how biodiversity recovers as restoration progresses.
Baseline eDNA Survey: Unlocking Hidden Biodiversity in Seagrass Meadows
Before starting the first restoration trial in Roches Noires, Bel Ombre, and Mont Choisy our team carried out a baseline biodiversity survey using environmental DNA (eDNA). This innovative method detects traces of DNA that organisms leave behind in water and sediments, allowing us to build a picture of the species present without needing to catch or observe them directly. Additionally, seven swab samples were collected to complete the reference barcode library for locally targeted commercially important fish species at Nature Metrics.
Samples were collected in both healthy seagrass meadows and nearby sandy bottoms. The results revealed clear differences between habitats: seagrass sites hosted a richer and more diverse community than expected, including species that were only associated with seagrasses. Many of the organisms identified – from small invertebrates to juvenile fish – are known to rely on seagrass for food, shelter, or nursery grounds.
Establishing this baseline is critical. It gives us a reference point against which we can measure change in the coming years, as restored plots begin to develop. By repeating the eDNA surveys after restoration, we will be able to track whether biodiversity returns and whether restored meadows start to function as healthy ecosystems again.
This survey marks an important step in linking cutting-edge science with practical restoration. It highlights not only the ecological richness hidden within seagrass meadows, but also the role of eDNA as a powerful monitoring tool for the future.
