Growth performance of bath sponge (Spongia officinalis Linnaeus, 1759) farmed on suspended ropes in the Dardanelles (Turkey)

Commercial bath sponge population in the Mediterranean has been recently reduced due to diseases and the depletion of natural banks. The commercial supply is far below the demand on the last 1015 years. In this study, we aimed to investigate the farming performance of Spongia officinalis in the Dardanelles. Sponges collected from the Dardanelles cut into pieces of different weight. They were divided into two groups depending on the wet weight ranging from 50 to 150 g (mean weight 102.6 +/- 4.81 g) and from 160 to 360 g (mean weight 235.8 +/- 8.56 g). Three rope systems located parallel to each other with 67 m inter-distance were constructed for the cultivation of sponges. At the end of the study, while small-sized sponges could reach mean wet weight of 120.7 +/- 14.8 g, large-sized sponges reached mean wet weight of 247.6 +/- 22.4 g. Growth rates were estimated 517% at 21st month. The survival rates were found 82% and 88%.