[2] Native to Northern and Western Africa, and the Middle East, through introductions it is now also established elsewhere, including parts of the United States, where it has been declared an invasive species and has caused significant environmental damage.

[3] O. aureus is primarily herbivorous, but occasionally consumes zooplankton;[3] the young include small invertebrates in their diet.

[8] Oreochromis aureus has been introduced in many places around the world for use as a food fish, and frequently in order to control aquatic vegetation.

It was at one time responsible for inhibition of the population of largemouth bass in Lake Trinidad (in Henderson County) until it was extirpated, and is implicated in the unionid mussel declines in two bodies of water in Texas.

[6] It is also blamed for a severe decline in native fish populations in Warm Springs Natural Area, Nevada.