Wildlife & Habitat


Green Cay is a small, 14-acre, uninhabited island about 1,650 feet in length (northeast to southwest) and approximately 500 feet in width at its widest point. The island is about 1,200 feet north of Chenay Bay beach on the main island of St. Croix.

  • St. Croix Ground Lizard

    This island refuge provides critical habitat for the largest remaining natural population of the federally endangered St. Croix ground lizard. Its extirpation from the main island of St. Croix, just several hundred yards away, is generally attributed to the modification and loss of shoreline habitat resulting from human activities, and the introduction of predators, such as mongoose, rats, cats, and dogs. The introduction of the exotic Indian mongoose likely completed the elimination of the species from St. Croix. As a result, this species is one of the rarest reptiles in the world and is unique to St. Croix island ecosystems.

    Check out our St. Croix Ground Lizard Fact Sheet for more information! (english/spanish)

  • Shrublands

    Shrublands occur in dry locations at low elevations on all islands, including Cays such as Green Cay and Buck Island. Because vegetative growth is limited by thin, infertile soils, strong winds, and minimal moisture, shrubland vegetation is relatively short, typically ranging from 2-15 feet in height. Nevertheless, shrubland vegetation is often dense and sometimes nearly impenetrable to humans. Bushy, multiple-stemmed shrubs that are often thorny and have interlocking branches typically dominate the vegetation of this habitat. Cacti and other succulents may be interspersed among the shrubs. 

  • Grasslands

    Grasslands occur in areas with very low rainfall or subjected to frequent disturbance by agriculture, grazing, fire, or mowing. In the Virgin Islands, most grasslands are anthropogenic, that is, a result of human activity, and represent an early stage of succession. Grassland-dominated communities with less than 10 percent cover from shrubs and trees are referred to as pasture, which is maintained by grazing or fire. When such communities are covered 10-25 percent by shrubs and trees, they are referred to as pasture mixed scrub; this usually results from succession when grazing is discontinued and fire excluded. Mixed dry grassland is 25-50 percent covered by shrubs and trees, and usually results from selective grazing by livestock that shun spiny or poisonous plants. Coastal grassland occurs naturally where extreme conditions from wind, salt spray, and low moisture combine to preclude the survival and growth of woody plants, thus enabling the growth of grasses adapted to such harsh environments.

  • Cays

    More than 50 small, mostly uninhabited islands, collectively referred to as “Cays,” are sprinkled throughout the USVI and comprise about three percent of the territory’s total area. Because of their relative inaccessibility and the scarcity of predators on many of them, the Cays provide sanctuary for a variety of wildlife species and are especially important for colonial nesting seabirds. The varied vegetation formations on Cays include subtropical dry forest, shrublands, and grasslands. When present, salt ponds and their associated mangroves provide habitat for a variety of invertebrates, shorebirds, and indigenous waterbirds. Sparsely vegetated geological formations (such as cliffs, rock outcrops, and beaches) provide habitat for nesting seabirds and other wildlife.