Nile tilapia, originally from Eurasia and Africa, is a very dangerous invasive species according to Cleber C. Figueredo and Alessandra Giani of the Federal University of Minas Gerais in Brazil because of its significant impact on ecosystems that it invades. Furthermore, it has tremendous potential to spread even further throughout the United States and the rest of the world.
Their goal was to determine what impact that the tilapia had on several ecosystems in Brazil terms of water condition and the phytoplankton community. In their study, the researchers discovered that Nile tilapia have increased the quantity of nitrogen and phosphorus in the water. Furthermore, they have changed algal composition, biomass, as well as water quality. Most importantly, Figueredo and Giani urge caution when tilapia are used in aquaculture so as to prevent extreme environmental problems for native species.