THE GRAZING OF AURELIA sp.1 ON SKELETONEMA COSTATUM AND PROROCENTRUM DONGHAIENSE
海月水母(Aurelia sp.1)对中肋骨条藻(Skeletonema costatum)和东海原甲藻(Prorocentrum donghaiense)摄食的研究

The effects of different microalgal species and cell densities on the feedings of polyps, ephyrae and medusae of Aurelia sp.1 under controlled laboratory conditions were investigated. Two species of microalgae, Skeletonema costatum and Prorocentrum donghaiense, were used. Different microalgal species and cell densities had significant effects on the feedings of polyps, ephyrae and medusae. With the increasing of microalgal cell desities, the ingestion rates (IR) of polyps and ephyrae increased while the clearance rates (CR) decreased. The maximum IR of polyps on S. costatum and P. dong-haiense were 4623 and 4118 cells/(ind·h), respectively, while the maximum IR of ephyrae on S. costatum and P. dong-haiense were 174671 and 47218 cells/(ind·h), respectively. At similar microalgal cell densities, the IR of ephyrae on S. costatum were higher than those on P. donghaiense, and the IRof ephyrae were higher than those of polyps. The adaption of microalgae made IR of polyps increased about ten times. Medusae did not feed on S. costatum and P. donghaiense.