[Diet composition and feeding habits of juvenile Acipenser sinensis in Yangtze River estuary]

This paper dealt with the diet composition and monthly variation in feeding habits of juvenile Acipenser sinensis accidentally caught along with other fish in Yangtze River estuary from May to September, 2004. The results showed that the juvenile A. sinensis mainly fed on demersal fish, polychaeta and amphipoda, as well as some small-sized benthic invertebrates including shrimp, crab and bivalve. The feeding rate and intensity were higher, and the feeding intensity varied monthly. The main food items also varied monthly, and changed from small-sized to relative large-sized species. The main diet composition included polychaeta and crab in May, fish and amphipoda in June, fish and polychaeta in July, empty stomach in August, and fish and shrimp in September. In the diet, the proportion of Platycephalidae, an important prey of juvenile A. sinensis in the past, was very low, only accounting for 1.81% of the total food by mass, while that of Gobiidae and Isopoda, which had not been recorded in the diet, was higher, accounting for 50.54% and 10:07% of the total, respectively.