About Oreochromis aureus (Steindachner, 1864)
In the introduced range of the blue tilapia (Oreochromis aureus) in the United States, adults are typically 120 to 200 millimetres (4+3⁄4 to 7+3⁄4 in) long, and reach weights of 5 to 6 lb (2.3 to 2.7 kg). The largest recorded specimen measured more than 21 in (53 cm) long and weighed over 10 lb (4.5 kg). Blue tilapia are mouthbrooders, and each female carries a brood of 160 to 1600 eggs. O. aureus is primarily herbivorous, but will occasionally eat zooplankton; juvenile blue tilapia include small invertebrates in their diet. The blue tilapia is native to Northern and Western Africa, and the Middle East. In Africa, its native range covers the Senegal, Niger, Benue, and lower Nile Rivers. In the Middle East, it is native to the Jordan River. Via human introduction, the species is now found in the United States in Texas, Alabama, Florida, and Nevada. It has also become established in Central America, South America, and Southeast Asia. The original populations of O. aureus introduced to the United States originated from Israel. Blue tilapia are primarily found in fresh and brackish water, and inhabit a wide variety of habitat types including streams, rivers, lakes, and ponds. They have a high tolerance for salt water, and can even survive in hypersaline conditions with up to 4.5% salinity (for comparison, seawater has an average salinity of ~3.5%). They most commonly live in waters with temperatures between 12 and 32 °C (54–90 °F), but can tolerate temperatures ranging from 8 to 40 °C (46–104 °F).
