In the coastal waters of central Western Taiwan,Chinese white dolphin(Sousa chinensis)was more abundant in the Xin-hu-wei Estuary(Ex).In order to explore the mechanism,we conducted field measurements seasonally from 2012 to 2013 for two years and applied Ecopath with Ecosim to construct trophic models at three study sites(Ez,Dm,Ex)to examine energy flow from primary production to top predators.The results of the Ex Ecopath model revealed that only small proportion of phytoplankton production was directly consumed by herbivores.Most of phytoplankton productionflowed into the detrital pool,and was utilized by benthos.In the Ez and Dm models,phytoplankton net production was lower,and then provided less detritus to benthos.Consequently,Chinese white dolphins,benthic fish and invertebrates were more abundant at Ex,because of higher phytoplankton production.The carrying capacity was estimated 35 individuals.We further applied Ecosim to explore the impacts of removing Chinese while dophin on the coastal ecosystems.The simulation results showed that the prey fish might increase,but some other fish and macroinvertebrates might descrease,specieally the crab Portunus pelagicus and the shrimp Metapenaeopsis barbata with high economic values.