Three species of the family Cichlidae have been reported from Western Australian waterways, including Tilapia zillii, Oreochromis mossambicus and Geophagus brasiliensis. While T. zillii was first found in 1975 and was successfully eradicated, O. mossambicus was first recorded in natural waterways of Western Australia in 1981, and has since spread to a further three river systems through either human-assisted dispersal or from flooding events.
Recent research assessing the distribution and impact of the species in Western Australia suggests that O. mossambicus poses a serious threat to the unique aquatic fauna of Western Australian inland waters, including estuaries. The entry of other cichlids into the State’s waterways, including G. brasiliensis, which was first discovered in 2006, has the potential to impact Western Australia’s unique aquatic fauna in both inland freshwaters and estuaries
