Species composition and quantity distribution of ichthyoplankton in Luoyuan bay in summer

The species composition and quantity distribution of fish eggs,larvae and juveniles in Luoyuan bay in summer 2009 were studied.It was found that 19 eggs,larvae and juveniles were identified during this survey,belonging to 13 families,among which 10 eggs and 14 larvae and juveniles were included.For fish eggs,larvae and juveniles in Luoyuan bay in summer,the mean densities were 1.80 ind/m3 and 0.54 ind/m3 by horizontal trawling,and 4.11 ind/m3 and 2.63 ind/m3 by vertical trawling.Species in Engraulidae family were the most abundant,and the dominant species were Thrissa mystax and Stolephorus commersonli.Compared with the past,the species numbers of ichthyoplankton were decreasing,and the dominant species varied from several coexisted family fish to dominated species in Engraulidae family.The distribution area of high abundance region for ichthyoplankton in summer appeared in the central and northern part and bay mouth of Luoyuan bay.