Abstract:

Aims: Our objective is to provide a better understanding on the background and community structure of fish diversity in inland waters of Shanghai. 

Methods: We use specimens from 13 rivers and one reservoir in Shanghai to investigate the species resources and community structure of fish in the inland water bodies of Shanghai. These specimens were examined qualitatively and quantitatively from July to August and then from October to November in 2023.

Results: A total of 20,160 specimens were collected of which16 orders, 24 families, 57 genera, and 71 species are identified. Included are Cypriniformes, Gobiiformes, and Siluriformes which account for 57.74%, 9.86%, and 5.63% of the total species, respectively. There are 57 species of freshwater fish, 11 species of estuarine fish, 3 species of migratory fish, and 4 exotic or artificial species. The high taxonomic composition of series Percomorpha and the rich ecological types of estuarine fish represent the characteristics of fish composition in estuarine tidal river networks in eastern China. The 14 water bodies average 35.9 species of fish each. The Punan Canal and Pudong Canal have the largest number with 47 species each, and Dishui Lake has the smallest number with 24 species. There are 15 dominant species and 14 common species with the average being 5 dominant species and 10 common species in each water body. Carassius auratus, Acheilognathus macropterus, Culter dabryi, and Chanodichthys erythropterus are the dominant species in the 14 water bodies. The richness index (D), diversity index (H'), evenness index (J'), and dominance index (C) show fish diversity is higher in the 13 rivers such as Yuanxie River and lowest in Dishui Lake. The βc diversity index of each water body ranged from 4.0–15.5 with an average of 9.9. A large species diversity is shown by the βr diversity index ranging from 12.44 to 28.76 with an average of 19.8. The ABC curve shows W is negative in most water bodies, and the abundance dominance curve is mostly above the biomass curve, showing the characteristics of community structure dominated by small and medium-sized individual fish. The fish communities in 14 water bodies could be divided into 4 groups by cluster analysis. 

Conclusion: The similarities within the groups are approximately 74%, with the exception of the first group, and the differences between the groups are 31.42% – 49.65%. The highest contribution of differences is Carassius auratus, Pseudorasbora parva, and Chanodichthys mongolicus. Our results suggest the differences of fish community structure of inland water bodies in Shanghai may be caused by natural conditions, regional location, release activities of the water bodies, and the land use forms where the water bodies are located. The water of the national central city with dense buildings can also maintain a high diversity of fish species under the premise of protecting the water environment and fish habitat.

Key words: Inland water body of Shanghai, species diversity of fish, fish community structure, background survey