In this study, eDNA technology and traditional trawling methods were used to detect the species diversity of fish in the wetland ecosystem of the South China Sea at the mouth of the Pearl River in China. The results showed that eDNA technology could detect 32.05% more fish species than the traditional trawl method, and it was significantly higher than the latter in each season. A total of 78 species were detected by 11 species, involving 33 families, 60 genera and 5 unknown groups. The results show that eDNA technology is more sensitive, accurate and efficient in the detection of marine fish diversity, and can be used for long-term monitoring of biodiversity in coastal ecosystems.
