Fish Diversity Monitored by Environmental DNA in the Yangtze River Mainstream

Hui Jia,Hui Zhang,Weiwei Xian

doi:10.3390/fishes7010001

Abstract

Surveys and assessments based on environmental DNA are not only efficient and time-saving, but also cause less harm to monitoring targets. Environmental DNA has become a common tool for the assessment and monitoring of aquatic organisms. In this study, we investigated fish resources in the Yangtze River mainstream using environmental DNA, and the variations in fish during two seasons (spring and autumn) were compared. The results showed that 13 species were identified in spring, and nine species of fish were identified in autumn. The fish with higher eDNA detection were Sinibotia superciliaris, Tachysurus fulvidraco, Cyprinus carpio, Ctenopharyngodon Idella, Monopterus albus, Acanthogobius hasta, Saurogobio dabryi, Oncorhynchus mykiss, Mugil cephalus, Odontamblyopus rubicundus. Seasonal variation between spring and autumn was not significant, and the environmental factors had different effects on fish assemblages during the two seasons. Our study used the eDNA technique to monitor the composition of fish in the spring and autumn in the Yangtze River mainstream, providing a new technology for the long-term management and protection of fishery resources in the region. Of course, problems such as pollution and insufficient databases are the current shortcomings of environmental DNA, which will be the focus of our future research and study.

Highlights

As the largest river in Asia, and the third largest river in the world, the Yangtze River is rich in resources and has many tributaries and lakes, forming an important economic link connecting the east and the west of China [1]
Our study investigated the composition of fish diversity in the spring and autumn in the Yangtze River mainstream, showing that environmental DNA (eDNA) technology can be used to investigate fish diversity
We investigated the fish composition in the spring and autumn in the Yangtze River mainstream in 2019 through eDNA technology, which provides a reference for future surveys on the Yangtze River mainstream

Summary

Introduction

As the largest river in Asia, and the third largest river in the world, the Yangtze River is rich in resources and has many tributaries and lakes, forming an important economic link connecting the east and the west of China [1]. The variety and output of Yangtze River fish rank first in China [1]. The fishery resources in the Yangtze River mainstream have gradually declined in the past half century [2]. The government has gradually implemented relevant fishing bans in key waters such as the mainstream of the Yangtze River and important tributaries. Manage and protect these key regions, it is essential to develop better monitoring approaches for biodiversity [4]

Objectives

Methods

Results

Discussion

Conclusion