Coral reefs of the Virgin Islands other coral larvae to attach to and grow on. These corals can form into three different structures; fringing reefs, which are reefs that are close to the shore, barrier reefs, which are reefs that are alongside the shore and is separated by deep water, and an atoll reef which is a coral reef that circles a lagoon or body of water. As stated, the coral reefs such as fringing reefs, deep reefs, patch reefs and spur and groove formation are distributed over three islands in the Virgin Islands which are St. Croix (Salt River Bay National Historical Park and Ecological
Coral Sea whitetip reef shark ("Triaenodon obesus", 21%), silvertip shark ("Carcharhinus albimarginatus", 10%), tiger shark ("Galeocerdo cuvier", <1%) and great hammerhead ("Sphyrna mokarran", <1%). The interaction rate (free diving) at the Coral Sea reefs ranged from a few to 26 sharks per hour. The rare "Etmopterus dislineatus" shark species is endemic to the central part of the Coral Sea. It has been observed at depths of 590–700 m on or near the continental slope. The coastal areas of the Coral Sea were populated at least 40,000 years ago by prehistoric people descending through the northern islands. Those Aboriginal tribes have been dispersed