What is meant by "alien species" invasion? Name one plant and one animal alien species that are a threat to our Indian native species.
New species entering the geographical region are known as alien species. Introduction of alien species causes a significant loss to the biological community. However, some of the species are able to establish the area. Such successful exotic species eliminate the native species to the point of extinction, and so alter the habitat that many native species are no longer able to persist.
For example introduction of Nile perch into Lake Victoria disturbed the ecosystem of the lake by eliminating several native species of small cichlid fishes.