Feeding behavior of 5 species filter-feeding bivalves on Paralichthys olivaceus feed, fecal and sediment particulates in cage farming area.
5 species bivalves 'feeding behavior on different food, including flounder (Paralichthys olivaceus) faeces, residual feed and deposition was studied so as to discuss the potential IMTA based on filter-feeding bivalves. Results showed the 5 species bivalves could feed on fish faeces, residual feed and deposition. However, different species showed different feeding behaviors. Ingestion rates of oyster, clam and scallop were significantly higher than the other 2 species (two-way ANOVA, P<0.01), and absorption efficiency (AE) and absorption rate (AR) of the 5 species bivalves were not significantly different. Diet had significant influence on the feeding behavior. With particle organic matter (POM) increasing, AE increased. There were significantly linear relationship between AR and POM. TPM threshold for pseudo-feces production of oyster and scallop and was 26.24, 21.64, 27.00 mg/L, respectively, and the 5 species bivalves could regulate food intake by pseudo-feces production. The shellfish+fish IMTA mode, clam Ruditapes philippinarum, oyster Crassostrea gigas and scallop Chlamys farreri are relatively good candidate species.