Survey on Shellfish Resources of Intertidal Zone of Duliujian River Estuary in Tianjin

The shellfish resources survey of intertidal zone of Duliujian river estuary in Tianjin was carried out in september 2008 and 2013, respectively. The results show that the shellfish species in this area included 2 classes, 3 subclasses, 4 orders, 12 families and 18 species, among these species, the economic values of Ruditapes philippinarum and Cyclina sinensis distributed mainly in the middle tidal zone were higher, and the habitat densities of two species were 112.7 ind /m2 and 12.0 ind / m2, the average biomass was 334.1 g/m2 and 86.0 g/m2, and the commodity rates were 36.4% and 22.2%, respectively. The shellfish of this area in 2008 was 15 species, and Ruditapes philippinarum and Cyclina sinensis were not found. The high densities of Ruditapes philippinarum and Cyclina sinensis were closely related to enhancement and release of shellfish in surrounding waters in recent years.