Sept 04, Colombo: A recent survey carried out by the Secretariat of Bio-diversity of Sri Lanka reveals that a large number of aggressive flora and fauna species have spread in the island.

Out of the 43 species identified, 28 are flora species and 15 are aggressive foreign fauna species.

These invasive alien species are a threat to the existence of the indigenous species and damaging the balance of the island's environment biologists say.

The Secretariat with the assistance of Millennium Environment Programme has launched a five year programme at a cost of 2.5 million US dollars to control the spread of these aggressive foreign species.