blue tilapia Oreochromisaureus (Steindachner, 1864)
Origin
Oreochromis aureus, Blue tilapia is a freshwater fish native to North Africa and the Middle East. Adults are grey-blue shading lighter towards the belly. There may be dark broken lines running vertically along the body. The borders of the dorsal and caudal fins are red to pink. The spiny dorsal fin and the soft dorsal fin are joined. The males are usually larger and reach up to 20 in. (50.8 cm) in length.
Life Cycle
O. aureus can breed in freshwater or brackish water with a minimum temperature of 68° F (20° C). Females deposit eggs in single clutches and then take the eggs into their mouth after fertilization. The females protect the eggs until they hatch about 3 days later. Young O. aureus remain protected in their mother’s mouth until they are about 0.4 in. (1 cm) long after which they remain near their mother’s for about five days before going on their own. O. aureus does not have strict habitat requirements for reproduction, so introduced populations can take up all available habitat for breeding sites.
Distribution
O. aureus has been reported in Alabama, Arizona, Arkansas, California, Colorado, Florida, Georgia, Hawaii, Idaho, Kansas, Nevada, North Carolina, Oklahoma, Pennsylvania and Texas. O. aureus has been used as a food fish and introduced around the world.
Control Efforts
Preventing further spread of O. aureus to wild populations should be a high priority. Extra care should be taken when setting up stock ponds to decrease the chance of O. aureus escaping into the wild. Promoting fishing of O. aureus has been recommended to help control populations.