Introduction of alien species has led to environmental damage and decline of indigenous species. Give any one example of how it has affected the indigenous species?

Explanation

Invasive alien species are plants, animals that are non-native to an ecosystem, may cause environmental harm or may pose an adverse impact upon biodiversity, including decline or elimination of native species - through competition, predation, or transmission of pathogens and the disruption of local ecosystems and ecosystem functions. E.g., Nile perch introduced in lake Victoria eventually led to the extinction of an ecologically unique assemblage of more than 200 species of cichild fish. Parthenium/Lantana/water hyacinth caused environmental damage and threat to our native species. African catfish-Clarias gariepinus introduced for aquaculture purposes is posing a threat to the indigenous catfishes in our rivers.