Tilapia

Tilapia. Images: Department of Employment, Economic Development and Innovation (DEEDI), Queensland

The black mangrove cichlid or ‘spotted tilapia’ (Tilapia mariae) and the Mozambique tilapia (Oreochromis mossambicus) were illegally introduced into Australian waterways during the 1970s. Both species have become well established in the relatively short time since their introduction.

At first they were probably released as unwanted aquarium fish, and Mozambique tilapia are now established in catchments in tropical and subtropical Australia while black mangrove cichlids are mostly restricted to northeast Queensland. Both tilapia species are declared invasive pests in most Australian states. The rapid rate at which both species are spreading, together with evidence from overseas studies, suggests that they will have harmful impacts in Australia.