Nature relies on delicate balances. An alien species, whether deliberately or accidentally introduced into a habitat, may find conditions so favourable that it becomes invasive. Miconia, an ornamental bush introduced to Tahiti in 1937, now covers two-thirds of the island. Caulerpa, a tropical seaweed, monotonously blankets vast areas of the mediterranean. The water hyacinth, originally from Brazil, chokes rivers in Africa. In Hawaii, the Indian mongoose was released to eradicate rats in sugarcane fields. The mongoose did nothing to slow the proliferation of rats, but instead destroyed most of the local native flora and fauna of the island, bringing many of those species close to extinction.
To avoid an ecological disaster, do not release any exotic animal into the environment, and never smuggle plants or animals in your luggage..
-Abrams, “365 Ways To Save The Earth”, 2008