A Study on the growth performance of sea bass (Dicentrarchus labrax) in the eastern Black Sea

SUMMARY A Study on the Growth Performance of Seabass (Dicentrarchus labrax) in the Eastern Black Sea. The growth performance of sea bass {Dicentrarchus labrax), which has been cultured in a few commercial farms, in the Eastern Black Sea Region have been determined. Hatchery produced fish with a age of 0+ year old and mean initial size of 35.6±10.99 g and 14.7±1.46 cm (n = 50) were used. In the period of January to April (8 - 13 °C) there were considerable weight losses (3.6 %), but growth rates increased with increasing water temperature. The maximum growth rate (42.5 %) was observed during August (25 - 28 °C). At the end of the second growing season (after 350 days), fish reached a mean size of 128.8+29.63 g and 22.9±1.65 cm. The specific growth rates also varied with temperature and ranged from -0.06 % to 1.1 %, while the condition factor changed between 1.04 and 1.15, and did not appear to be affected by variation in temperature. Mean daily food consumption is 0.89 % and food conversion ratio were varied between 1.32 - 7.52. Length - weight relationship has been estimated as W = 0.01 lx L298 (r=0.932; n=50) at the start of research and W = 0.009xL283 (r=0.964; n=60) at the end of research. It has been concluded that the food consumption and conversion ratios and in consequence the growth performance was mainly determined by water temperature and there is a substantial growth only during 6 months of the year. As a result, it appears that time required for minimum marketing size (around 250 g) in tanks or ponds might take at least around 3 growing season. Key Words: Sea Bass, Dicentrarchus labrax, Eastern Black Sea, growth performance, food consumption, food conversion ratios. VI