A study on the development of fouling communities on the fish cage netting treated and untreated antifouling paint

Problems caused by biofouling event on net-cages due to changes on water column peculiarities by fish farming activity create difficulties in the sector. This study was planned at an aquaculture facility in Engeceli Harbor (Karaburun-Izmir) during the period between December-2000 and March-2000. In the study; fouling developments on the nets treated and untreated with antifouling paints were investigated for 3, 6, and 9 month periods. Dominant species, coverage index of present groups, individual numbers and biomass of each group, total biomass on net cages and closeness ratios of net gaps (%) were calculated. High number of individual of Crustacea, which was the dominant group on the treated nets were observed in all periods. The species, Elasmopus rapax, was the most dominant species within this group showed more dominant characteristic in this group. The release time of the net into the sea as well as the remaining time of nets in marine environment were important for changes in biomass both on the treated and the untreated nets. Total biomass of fouling organism and closeness ratio of net gaps showed changes between treated and untreated nets. The biomass on the untreated nets were higher than those on the treated nets for all periods. The nets closeness ratios were determined as %100 for untreated nets left in marine environment during 6 months for June and 9 months for December. During these periods, the net closeness ratios on treated nets varied between %68 - %74. Key words: Antifouling, fouling organism, fish farming, net-cage, Aegean Sea