Q26 of 30 Page 1

Alien species are highly invasive and are a threat to indigenous species. Substantiate this statement with any three examples.

An invasive species is a species that is not native to a specific location, and that has a tendency to spread to a degree believed to cause damage to the environment, human economy or human health. Spread of alien species is a threat to indigenous species. Some examples are:

a. The Nile perch introduced into Lake Victoria in east Africa led eventually to the extinction of an ecologically unique assemblage of more than 200 species of cichlid fish in the lake.


b. African catfish Clariasgariepinusfor aquaculture purposes is posing a threat to the indigenous catfishes in our rivers.


c. Invasive grass like Parthenium, Lantana camara have proven to be a threat to the native biodiversity of many regions in our country.


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