Feeding habits of Setipinna taty and its relationship with environmental factors in southern coastal waters of Zhejiang, China.

Abstract

Setipinna taty, a dominant fish species in the southern Zhejiang coastal waters, plays an important role in the coastal marine ecosystem. Based on 847 S. taty samples collected from southern Zhejiang coastal waters between May 2020 to January 2021, we examined prey composition, seasonal and ontogenetic diet variations, as well as their relationships with environmental factors, with stomach content analysis, cluster analysis, and canonical correspondence analysis (CCA). Results showed that S. taty consumed 43 prey species, with shrimp, Amphipoda and krill as the most important prey groups. The dominant prey species were Leptochela gracilis, Oxycephalus clausi, and Euphausia pacifica. There were significant seasonal and ontogenetic variations in the prey composition of S. taty. Shrimp was the dominate prey group in all seasons. S. taty consumed certain amount of fish in summer and a high proportion of Euphausiacea in winter. With the increases of body length, the main prey species gradually shifted from small size prey items such as copepods to larger ones such as fish and shrimp. Results of CCA indicated that salinity and pH were the main factors influencing feeding habit of S. taty, followed by water depth, latitude and body length. This study could provide basic information for the food web study in the southern Zhejiang coastal waters.