Mass Alien Fish Species in the Fish Fauna of Inland Waters in Central Vietnam

At present, invasive fish species dominate in terms of abundance and compete for environmental resources and ecological niches with native species in some freshwater waterbodies and watercourses of Central Vietnam. This may ultimately lead to a decrease in the diversity and to the transformation of fish communities. Data on the distribution and biology of the mass alien species posing the most serious threat to tropical freshwater ecosystems, including in Vietnam-suckermouth-armored catfishes Pterygoplichthys spp. (Loricariidae) and Nile tilapia Oreochromis niloticus (L.) (Cichlidae)-are analyzed. These invasive species are shown to possess high adaptive potential. It is noted that invasions, as well as the intentional and unintentional introduction of alien fish species, may have negative consequences for the biodiversity of Vietnamese aquatic ecosystems.