Application of a complex ecosystem model to evaluate effects of finfish culture in Pagasitikos Gulf, Greece

In order to support management decisions for aquaculture, a modeling tool capable of simulating the ecosystem response was developed and is presented here. The impact on the Pagasitikos gulf ecosystem from two marine fish farms, one in a well protected cove and one in a more exposed area of the gulf, is explored and analyzed in the framework of the INSEA EU project. Model results show little effects of nutrient inputs near the exposed site. It appears that effluents from the exposed site may affect more distant areas due to hydrodynamic transport, while effects in the well protected site are more localized and intense (hot spot). Additionally, as the system dynamics are driven to large extent by the seasonal physical variability, the effect depends not only on the location of the farm but also on the season. Planning decisions for coastal areas require integrated management policies based on holistic approaches that include as many system components as possible. The tool capabilities illustrated by the simulation results demonstrate its role in supporting management decisions.