The decline or elimination of native species can occur through:
- Competition(Ex: Lantana camara, also known as Spanish Flag reproduces and spreads very quickly and poses a threat to other native species in few eco-systems)
- Predation (EX: Rattus rattus, commonly known as the ship rat has caused extinctions and catastrophic declines of native birds on islands)
- Transmission of Pathogens (Ex: Pathogens such as avian influenza A(H5N1)are attacking various organisms.)
- Disruption of natural eco-system(Ex: Eichhornia crassipes, commonly known as Common Water Hyacinth has lead to disruption many ecosystems by choking lakes and making them unfit for fish.)
The problem can be best tackled by raising awareness among individuals and cooperation between governments. However, it might not be possible to stop the movement of organisms (especially microbes and plants) from one region to another in this era of globalization.