This paper is mainly focused on a comprehensive review of the effect of salinity fluctuation on feeding, transferring efficiency and growth of fish in wide habitats, which could help our research program on the contribution of higher trophic level carnivorous Japanese sea bass, Lateolabrax japonicus, in the marine ecosystem under experimental conditions. It was found that the response of fish to salinity was directly proportional to food consumption during different life history under specific temperature, showing specific-adaptation capacity for both freshwater and marine environment. Compared with regulation to ecological efficiency, mask factor, significant divergence has occurred in the salinity regime, indicating evident relationship between specific growth rate (SGR) and salinity. Based on the analysis, we here present a tentative hypothesis that the adaptive spectrum could be reflected in the potential response to the salinity effect during specific stage to explain that optimum energy saving may be approached at the isosmotic point in the curve of salinity vs potential energy. From the viewpoint of the nonlinear relationship between salinity and ecophysiological efficiency, a process-oriented test for the hypothesis would be necessary to monitor the impact of salinity-based variation on the ecological dynamics of indicator fish in the estuary of Changjiang River.