36 June 2012 Fig. 8. Rhabdosargus sarba fingerling grading. and then salinity was increased to the natural level of Abu Al Abyad Island (51 ppt) within seven days (2 ppt/day). Mortality was recorded during this acclimation period. In nursery tanks, fish were fed daily to satiation with sinking 0.3-0.9 mm fish feed (crude protein 50 percent, crude lipid 6 percent, crude fiber 6 percent, ash 10 percent, moisture 11 percent) for 60 days. After the nursing period, fish were harvested and the total number collected from the nursing tanks (125,685) reflected a survival rate of 84 percent. The greatest mortality in this culture phase was caused by monogenean parasites in the first week in one of the nursing tanks and it was controlled by copper sulfate pentahydrate at 0.05 mg/L for seven days. All harvested fish were graded using a stainless bowlshaped 12-mm mesh sieve and two size groups were obtained. The small size group, averaging 0.4 ± 0.1 g in weight and 2.5 ± 0.2 cm in length, amounted to 26 percent of the fish harvested and the larger size group, averaging 5.0 ± 1.6 g and 5.1 ± 0.7 cm in length, amounted to 74 percent of the total number harvested. Notes 1Aquaculture Center, Abu Al Abyad Island, Department of the President’s Affairs, P.O. Box 372, Abu Dhabi, United Arab Emirates, Fax: 00971-2-8839112, E-mail: omeryousif@gmail.com References Hesp, S.A., I.C. Potter and S.R.M. Schubert.2004. Factors influencing the timing and frequency of the goldlined seabream (Rhabdosargus sarba) (Sparidae) in the lower reaches of an estuary. Fisheries Bulletin 102: 648-660. Leu, M. Y. 1994. Natural spawning and larval rearing of silver bream, Rhabdosargus sarba (Forsskal), in captivity. Aquaculture 120:115-122. Mihelakakis, A. and C. Kitajima.1995. Spawning of the silver sea bream, Sparus sarba, in captivity. Japanese Journal of Ichthyology 42(1):53-59. Radebe, P.V., B.Q. Mann, L.E. Beckley and A. Govender. 2002. Age and growth of Rhabdosargus sarba (Pisces: Sparidae), from KwaZulu-Natal, South Africa. Fisheries Research 58:193-201. Fig. 5. Rhabdosargus sarba floating egg collection. Fig. 6. 1.8-mm hatchlings after 24 h. Fig. 7. Growth of Rhabdosargus sarba as related to food type.
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