Virgin Islands National Park is rich in natural resources. There are 140 species of birds, 302 species of fish, 7 species of amphibians, 22 species of mammals and 740 species of plants inhabiting the Island. In addition there are about 50 corals species and numerous gorgonians, and sponges providing St. Johnian's and visitors with some of the best snorkeling and diving in the world.

The only mammal native to St. John is the bat. Three of the six native species of bats are protected under the V.I. Endangered and Indigenous Species Act of 1990 (Act No. 5665) (Table 2). Some bat species are important pollinators of many floral species on the island as well as important seed dispersal agents for many species of fruit bearing trees and shrubs. Other species of bats consume vast quantities of insects, including mosquitoes.

Present day St. John does have many other species of animals that are not native to the island or even the tropics.  These include: deer, goats, sheep, donkeys, cats, dogs, mongoose and pigs.