Master of Science (MS)


Forestry, Wildlife, and Fisheries

Document Type



Juvenile (4 g) tilapia of four varieties, Nile tilapia (Oreochromis niloticus), blue tilapia (O. aureus), Florida red tilapia (O. urolepis hornorum x O. mossambicus), and Mississippi commercial tilapia (Oreochromis spp.) were tested for salinity tolerance. This was accomplished by subjecting them to four salinity regimes during a 97-h period with as long as 63 h acclimation. Salinity regimes represented salinities found along coastal Louisiana. Each variety was challenged individually against every other variety and thus in triplicate. All four varieties are commercially produced in the southeastern United States. The Florida red tilapia and Mississippi commercial tilapia are hybrid-based varieties (distinct species were crossed to produce their lineages). Juvenile O. aureus, O. niloticus, and Florida red tilapia exhibited good survival (> 81%) in salinity regimes up to 20 ppt, with moderate survival of O. aureus (54%) and Florida red tilapia (33%) at 35 ppt salinity. Mississippi commercial tilapia survived salinity regimes up to 10 ppt and exhibited poor survival at 20 ppt (5%). The potential for acclimation and survival of juvenile tilapia in Louisiana’s coastal aquatic habitats was evaluated based on a comparison of trial results with prevailing seasonal salinities in coastal waters. The study indicated O. aureus, O. niloticus, and Florida red tilapia could survive salinities throughout the year along coastal Louisiana. These results will allow Louisiana and other Gulf of Mexico states to more objectively evaluate risks associated with tilapia production in coastal watersheds by quantifying the salinity tolerances of two commercially important hybrid-based tilapia strains.



Document Availability at the Time of Submission

Release the entire work immediately for access worldwide.

Committee Chair

Charles G. Lutz