The aim of this study is to test the applicability of the statistical models, which were developed to predict fish and macro-crustacean responses to the environmental conditions in the Westerschelde estuary (Chapter 6). For this, a data set from the Oosterschelde was used. The probability of occurrence and the prediction of abundance of several dermersal fish and macro-crustaceans in reponse to four environmental variables (salinity, temperature, dissolved oxygen concentration and turbidity) are investigated. The present study can only be seen as a preliminary attempt to validate the robustness of the models that were established for another system. The diagnostics (% correctly predicted; sensitivity and specificity) for the 15 presence absence models based on the Oosterschelde data were comparable to the diagnostics based on the Westerschelde data. Only the models that explained >45% of the variance in density for six species in the Westerschelde, were applied to the density data from the Oosterschelde. These were largely successful when temperature was the main forcing variable (e.g. for Sprattus sprattus and Pomatoschistus microps ). The constant high salinity in the Oosterschelde is a favorable condition for Carcinus maenas and Liocarcinus holsatus , partially masking the effect of the other environmental variables in these models. Limanda limanda and Pomatoschistus minutus have different seasonal distribution patterns in both systems. In the Westerschelde both species only occurred during a relatively short period; while in the Oosterschelde they were present throughout the year. This shows the difficulty of applying statistical models from a real estuary to a different type of ecosystem, namely a marine bay like the Oosterschelde.