Growth of Tilapia mariae (Boulenger) fry in different salinities

Gradual salinity acclimatization and growth studies were performed on fry of the spotted tilapia, Tilapia mariae. First, fry were successfully brought to a salinity of 40%. in 8 weeks by gradual weekly increments of 5 %.. Second, fry were exposed separately for nine weeks to salinities of 0, 5, 10, 20, 25, and 30 %.. Fish grew best at 5 and 10 %. (p < 0.05) and least at 30 %.. At nine weeks, fish at 0, 5, 10, 20, 25, and 30%. appeared to be osmoregulating, as indicated by osmolarities of their inner body fluids. These results suggest that Tilapia mariae may become a competitive threat to fishes in native estuarine environments in southern Florida.