Invasive potential of common carp (Cyprinus carpio) and Nile tilapia (Oreochromis niloticus) in American freshwater systems

Normative fish introductions disrupt ecosystem processes and can drive native species to local extinction. Two of the most widespread, introduced species are the common carp (Cyprinus carpio) from Eurasia and the Nile tilapia (Oreochroniis niloticus) from Africa. In North and South America, these introductions stem from aquaculture facilities, as well as historical introductions for recreational angling. An emergent field of ecological niche modeling provides robust predictions of the geographic potential of alien species to better understand their capacity to become established at broad scales. We used this modeling approach to produce spatially explicit predictions of the invasive potential of common carp and Nile tilapia in the Americas. Model predictions were tested using occurrence data for established populations in their native area and in the Americas. Results indicated that predictive power of niche models was high. Distributional potential of common carp in the Americas covers most temperate regions and high mountain tropical aquatic systems, whereas that of Nile tilapia is focused in the tropics and coast areas. The consequences of the potential establishment of these exotic species can be profound on native aquatic faunas, particularly on highly diverse regions such as the Amazon Basin-and central Mexico.