Introduction to Reefs and Shorelines of the British Virgin Islands

Abstract

The British Virgin Islands form the eastern edge of the Greater Antilles island chain, lying on a carbonate microplate located on a subsiding island arc. There are over 60 high volcanic islands with granite-like magma intrusions on which the present reefs have developed, on approximately 420 km of coastline. Marine habitats around the volcanic islands include seagrass meadows, muds, carbonate banks and coral reefs. Most reefs are fringing reefs which have developed on narrow shelves which average 500 m in width between low tide and the 20 m depth contour. Some coral cays exist also, a number supporting rich mangroves. Tourism has become increasingly important, and with it a shift occurred in the BVI from preserving natural resources for local subsistence to its exploitation for economic gain; one aspect of the tourism being development of the world’s largest concentration of charter yachts which, initially at least, severely damaged several reefs by extensive anchoring. Reefs also suffer from shoreline development, resulting in extensive damage around the main populated island. Environmental legislation that did exist did not keep up with the advancement of scientific knowledge, and updating legislation has since become a well-recognized need in the BVI, with some success, though resources are insufficient. As with many Caribbean locations, the white-band disease of Acropora, and the Diadema mortality, along with (more recently) warming episodes, have caused substantial degradation to the reefs of the BVI.