Chervinski, J., Agricultural Research Organization, Fish and Aqua-Culture Research Station, Dor, Israel
Hering, E., Agricultural Research Organization, Fish and Aqua-Culture Research Station, Dor, Israel

Laboratory experiments were conducted to determine the adaptability of Tilapia zillii (Gervais) to various salt concentrations. It was found that the maximum salinity tolerance of T. zillii, on direct transfer, is between 60-70% sea water (S = 23.4-27.3‰). Through gradual adaptation the fish can withstand up to 100% sea water. Between T. zillii from Bardawil, a hypersaline lagoon, and from Daliyya River, a fresh water body, the following body proportions and morphological differences were found: H S.L. ( head standard length), D S.L. ( depth standard length), P.O. S.L. ( preorbital standard length), I.O. S.L. ( interorbital standard length). © 1973.