A genetic study of an introduced freshwater fish in Queensland reveals invasion, overthrow and expansion.
Tilapia are able to survive and breed in poor quality habitat. They are omnivorous and aggressive, readily displacing Australian native fish.
In Queensland, 21 coastal catchments contain tilapia and the number is rising all the time. But how do they do it?
Our paper combined dates of first occurrence and distribution patterns with genetic analyses. Movements between catchments of up to 300 km were reported that were consistent with the popularity of the species with the public (for use as live bait in aquariums and for food), despite regulations prohibiting its possession in Queensland.
Genetic analyses showed that tilapia in Queensland were not the ‘mossambicus’ type (Oreochromis mossambicus), but most likely to be interspecies hybrids of O. spirulus, hornouram and aureus.
See here for more details on this study.
