Non-native species are those whose presence in a region is deliberately or inadvertently attributed to human activities (Psyek et al., 2020). In a non-native region, non-native species go through a series of stages called transport, introduction, establishment and dispersal (Blackburn et al., 2011). At each stage, the physical, biological or ecological barrier phases, define whether the population becomes established (constant reproduction that maintains recruitment without migration) and disperses, becoming invasive (Blackburn et al., 2011; Pysek et al., 2020). Therefore, the study of non-native species should be conducted as early as possible to determine their invasive potential and prevent potential social, economic and environmental impacts.

For the management of invasive fish species in rivers, must be consider the nature of the invasion. Invasive fish species can be introduced accidentally through escapes from aquaculture farms or intentionally with a direct introduction in places where these have a high economic and social value (Gozlan et al., 2010). The established non-native fishes can impact environments at different ecological scales (individual, population, community and ecosystem) (Vitule et al., 2009; Gozlan et al., 2010; Cucherousset and Olden, 2011). Economic value and food for the human communities, and life history traits of non-native fish influence the successful for the establishment in rivers (Bernery et al., 2022) and determines the speed of the invasion. Thus, the invasion success of invasive fish in rivers is determined by the species, the environment, and anthropogenic factors.

In Colombia, aquaculture began in 1939 with the culture of a non-native trout Oncorhynchus mykiss in the Andes (Walbaum, 1972). Currently, non-native fish represent 70% of national production, with 30% being the production of white cachama (Piaractus brachypomus Cuvier, 1818), yamú (Brycon amazonicus Spix and Agassiz, 1829) and bocachico (Prochilodus magdalenae Steindachner, 1879) (Cruz-Casallas et al., 2011). For these reasons, doradas (Brycon moorei Steindachner, 1878) and cachamas (Colossoma macropomum Cuvier (1816), and Piaractus spp.) have been transplanted in other basins of the Colombian territory (Gutierrez et al., 2012).

For more than 20 years in the Atrato basin in Chocó Colombia, non-native species such as the black cachama (Colossoma macropomum), white cachama (Piaractus brachypomus), and tilapia (Oreochromis spp.) have been commonly captured. The cachama and tilapia were accidentally introduced to the Atrato River as a food security strategy and possible mitigation in areas disturbed by mining (Gutiérrez et al., 2012). Therefore, knowledge about non-native fishes in the Atrato River is necessary to protect it.