Assessment of physical carrying capacity of a mariculture zone designated in the Aegean Sea

The present study was conducted to evaluate the physical carrying capacity in a mariculture zone designated for cage aquaculture in the Aegean Sea (Mersin Bay, Izmir, Türkiye). Rapid assessment of carrying capacity for the approval of new investments or capacity increase requests environment-regulated timely management procedures for the sustainable development of the drastically growing cage aquaculture industry in the Mediterranean. Hence, the mathematical estimations earlier developed for the Mediterranean area have been applied for the carrying capacity assessment using the data gathered from eight fish farms operating in the area. The data collected from the farms comprised the information such as current granted production level, surface area, location depth, current speed, shore distance, and coordinates of the farm sites. The results obtained showed an estimated carrying capacity for the investigated mariculture zone as 252,852 tons which is about 18 times the current production level of 13,500 tons that was granted in total for the sum of eight cage farms in the region with a total of 50.89-ha surface area. It can be concluded that, with the condition of periodic environmental monitoring to keep the marine ecosystem below eutrophication risk, the production capacity of farms in the designated mariculture zone, comprising a surface area of 50.89 ha, could be increased by 18-fold over the present production level, which is far below the risk threshold. The findings of this study provide important support for decision-makers in the management of intensive cage aquaculture operations in the Mediterranean region.