Introduction of some alien species causes biodiversity loss. Justify the statement with an example .

Explanation

(i) The alien species become invasive and cause extinction or decline of indigenous species(eg) the Nile perch introduced into Lake Victoria in east Africa led to the extinction of more than 200 species of cichlid fish in the lake.
(ii) The environmental damage caused and threat posed to our native species by invasive weed species like carrot grass (Parthenium), Lantana and water hyacinth (Eicchornia).
(iii) Illegal introduction of the African catfish Clarias gariepinus for aquaculture purpose is posing a threat to the indigenous catfishes in our rivers.