Monitoring and assessing the species diversity and abundance of marine teleost around the Yellow River estuary in June using environmental DNA

The Yellow River estuary is an important feeding, reproduction, and development ground for a variety of marine economic species, and understanding the changes in species composition and abundance around the Yellow River estuary is of great significance. In this study, a trawl survey and seawater eDNA survey were carried out simultaneously around the Yellow River estuary with the objective of both understanding the composition of marine teleost around the Yellow River estuary and providing a reference for the application of eDNA in fishery resources surveys. The results showed that 31 species of marine teleost in total were detected using the trawl survey, and 33 species were detected using eDNA technology. The number of species detected by both methods was 21. In these 21 species, the Pearson’s correlation coefficients between their eDNA relative abundance and catch per unit effort (CPUE) were very high (0.993 for weight and 0.993 for quantity), while the Spearman’s correlation coefficients were 0.659 and 0.595, respectively. There were significant positive correlations between the biomass of specific species and their eDNA relative abundance. Species composition difference analysis based on eDNA showed that the species compositions of two low-salinity and low-water-depth survey stations were distinctly different from the others. This study not only scientifically monitors and evaluates the species diversity and abundance of teleost around the Yellow River estuary but also provides a reference for the application of eDNA in fishery resources surveys.