The U.S. Virgin Islands (USVI) are located at the northwest of the Lesser Antilles, a set of small islands in the eastern Caribbean basin. The archipelago comprises three main islands, St. Thomas, St. John and St. Croix, and more than 50 recognized cays and off-shore rocks to encompass a total land area of 346 km2 . The islands share common features of geology, climate, and ecology (Acevedo-Rodriguez 1996). St. Thomas and St. John, on the north, are geologically part of the Puerto Rican bank and were connected in the past, but St. Croix, located 60 km to the south, has a different origin.
The landcover of the USVI had a similar history as many other Caribbean islands, including nearby Puerto Rico. In the 17th and 18th centuries during the colonization process by European settlers, one of the main drivers of landcover change was the plantation primarily of sugar cane (Dookhan 1974), with other crops, such as cotton, tobacco and coffee also important (Acevedo-Rodriguez 1996). Trees were harvested for building materials, and these activities left all three main islands highly deforested.
Within the waters surrounding the islands, mangroves, seagrass beds, and several types of coral reefs provide essential habitat for marine organisms. Connectivity between marine habitats allows interchange between species and ecosystem services, and marine systems both support and are supported by terrestrial coastal habitats.
Broad habitat types that are used for planning restoration projects and describing where our species are found have been classified as Terrestrial, Wetlands, or Marine and are described below. In depth descriptions of these habitats and land use history can be found in the 2015 USVI State Wildlife Action Plan.
Terrestrial Habitats - The prevalent climate, soils, and topography of the Virgin Islands influence the growth and variation in terrestrial vegetation communities. With a subtropical climate, species are adapted to withstand seasonal drought that can last five months or longer, and to recover from recurrent disturbances from hurricanes. Due to easterly tradewinds, the islands exhibit an east-west moisture gradient with hot and dry conditions normal on the eastern ends, and more moisture influencing mesic vegetation communities moving west and along higher elevations. Terrestrial habitats consist of Forests, Shrublands and Grasslands, Beaches and Rocky Shorelines
Wetland Habitats - Wetlands refer to areas with soils sufficiently inundated or saturated by water that support vegetation adapted for life in saturated soils. These areas provide vital habitats for wildlife and fisheries, providing an array of goods and services including food, shelter from predators, protective nurseries, and filters of sediments and pollutants between landward human disturbances and sensitive coastal habitats including mangroves, coral reefs, and seagrass beds. Many wildlife species are dependent upon wetlands for their survival. Humans benefit from wetlands which slow down runoff, recharge freshwater aquifers, stabilize soils, offer a buffer protecting the land from storm surges, provide “hurricane shelters” for boaters, and afford aesthetic areas for recreation. Wetland habitats consist of Ghuts, Freshwater Ponds, Mangroves, Salt Ponds and Salt Flats.
Marine Habitats - Much of the focus on natural resource management in the USVI is on the marine environment. It provides an important food source for the community, including reef fish like grouper and snapper, open water deep sea fish like mahi-mahi and tuna, and invertebrates such as lobster, conch, and whelk. Commercial and recreational fisheries, and management of these resources, are important to the USVI economy. In addition, the azure ocean waters are the foundation of the tourist industry, a main contributor to the territory’s GDP, encompassing recreational activities such as diving, snorkeling, boating, and on-water activities like kayaking, surfing, and paddle-boarding. Tourists come to the USVI for the beaches, and spend money in hotels, bars, transportation, and entertainment. Besides food provisioning, employment, and recreation, other ecosystem services provided by the surrounding water include carbon storage and climate regulation. Mangroves and coral reefs buffer shorelines from severe wave action. Marine habitats consist of Seagrass Beds, Coral Reefs, Sargassum Mats, and Pelagic.
One of the major updates in this version of the USVI SWAP is the addition of major spatial analyses to guide conservation. These include:
Geodata and more details in the Caribbean Southeast Conservation Adaptation Strategy Blueprint data atlas and actions will be prioritized in the Conservation Opportunity Areas.
Updated National Wetlands Inventory data was published in October 2022 as a result of an EPA grant funding Ducks Unlimited and can be found here: https://www.fws.gov/program/national-wetlands-inventory/wetlands-mapper
Landscape Corridors for wildlife movement and dispersal
Credible data resources to identify habitats and species:
Mapgeos: https://usvi.mapgeo.io/ - if on federally owned land, direct applicant to federal agency or territorial agency if ownership is government or other organization.
Federal Critical Habitat:
DFW Sea Turtle Density Map: https://www.google.com/maps/d/edit?mid=1XIASfBTk0hj1P8mhp-w-MWbXUWYWxYD3&usp=sharing
DFW Wildmon Acoustic Data – find site and species list: https://dashboard.wildmon.ai/project/usvi-dfw-biodiversity-monitoring
USFWS Wetlands: https://www.fws.gov/program/national-wetlands-inventory/wetlands-mapper
NOAA Environmental Sensitivity Index and ERMA: login to https://erma.noaa.gov/