A number of animal species have been introduced in the forests of these islands from time to time. Cheetal (Axis axis) or the spotted deer was the first animal to be introduced in these islands by the Britishers in early part of the 20th Century.

These deer have multiplied rapidly in absence of any predator. Other animals introduced include Five striped palm squire, hog deer, barking deer, leopard, elephant, common mynah, house sparrow, grey patridge, peafowl, giant snail etc. Some of these introduced animals are believed to have caused ecological disturbances but no scientific study has been carried out so far on the impact of introduced fauna on the island ecosystem.