Antigua and Barbuda, together with the tiny uninhabited island of Redonda, are an independent Caribbean nation. Coral reefs are relatively widespread in the coastal waters. Antigua has some fringing reefs, but also more extensive, though intermittent, bank barrier reef structures offshore. Barbuda has extensive fringing reefs, particularly along its eastern coastline, topped by a well developed algal ridge. The reefs, particularly in nearshore areas, are reported to have been degraded in recent years, possibly due to increasing sedimentation and nutrient enrichment associated with coastal development. Offshore reefs and those to the north of Barbuda generally have higher coral cover and species richness. Hurricanes Luis and Marilyn caused further damage when they struck the islands in 1995.
Bahamas
The Bahamas, an archipelago of some 700 islands and numerous reefs, stretch over 1 225 kilometers from north to south. Most of these islands are scattered over two shallow banks, the Little Bahama Bank and the Great Bahama Bank, with depths of 10 meters or less bounded by extremely deep water of up to 4,000 meters. The Bahamas are named after these banks: baja mar is Spanish for “shallow sea”. The other islands occur on smaller, more isolated, banks to the southeast (principally the Crooked, Mayaguana and Inagua Banks) and the west (Cay Sal Bank). To the south, Hogsty Reef is one of the few atoll-type structures in the Caribbean. All the Bahamian islands have low relief and are formed from carbonate material, laid down by corals and calcareous algae, or by physical deposition from saturated water. Successive ice ages exposed these carbonate platforms, and wind-blown sand dunes created at much the same time subsequently lithified, further raising the elevation in some areas.
Barbados
Barbados is, in many ways, an anomaly. It lies east of the main Lesser Antilles chain in the Atlantic Ocean. Fringing reefs are largely absent, although there is a small fringing structure near Folkestone on the leeward west coast. There are also sub-surface reefs along this coast, where a gently sloping shelf extends about 300 meters seaward to a depth of 10 meters. At the edge of the shelf, the sea floor drops evenly to a depth of about 20 meters. Seaward from this there are further submerged patch reef structures, together with two larger bank barrier reefs, 12-20 meters deep and up to 100 meters wide. Offshore, submerged bank barriers are also found off the southeast coast. The eastern, Atlantic, coast is subject to very high wave energies throughout the year, and much of this coastline is a bare carbonate platform extending out to deep water. Nearshore reefs in Barbados have suffered considerably. Reef flat corals disappeared over 100 years ago with the intensification of agriculture, while considerable declines in coral cover and diversity have been reported on offshore reefs since the 1980s, linked to eutrophication from urbanization and tourism developments.
Cuba
Cuba is the largest of the Caribbean islands, with a long, complex coastline and considerable chains of offshore islands and coral cays. Coral reefs stretch along virtually the entire border of the Cuban shelf. The majority of these lie offshore in long tracts which resemble barrier reefs, separated from the main island by broad lagoons. The longest runs for some 400 kilometers along the north coast from the Archipiélago de Sabana to the Archipiélago de Camaguey. On the south coast a similar reef tract stretches for over 350 kilometers from Trinidad to Cabo Cruz. Unlike true barrier reefs, the lagoons behind these reef tracts are very shallow. In most cases these wide lagoons, together with the long archipelagos of small coral cays which lie on their outer edges, have protected the reefs from adverse anthropogenic impacts. Hurricanes are more frequent in the south and west where the reef communities are dominated by species resistant to sedimentation and water movement, especially in the Gulf of Batabanó.
Dominica
Dominica, a high volcanic island with steep topography, is an independent state. There is only limited reef development on the narrow coastal shelves, although there are several important coral communities, particularly on the south, west and northwest coasts. Several species of whale and dolphin are found in the waters around Dominica, which is fast positioning itself as the leading whale-watching destination in the region. The small population and minimal coastal development mean that the corals have not been severely impacted by human activities, and Dominica has been spared from a direct hurricane since Hurricane David in 1979.
Dominican Republic
The Dominican Republic occupies a fairly large land mass. There are large rivers and streams washing extensive watersheds, and usually there are no coral formations directly downstream from them. The Caribbean coast is basically made up of carbonate reef terraces allowing shallow fringing reefs to develop. On the northeastern region there are usually mountainous terraines close to shore, associated with higher pluviometry which in turn cause short torrential streams that drain into the adjacent sea, loading it with sediments, and limiting reef growth. This occurs for approximately 1/3 of the coastline. Along the rest of the coast reef growth is of the fringing or barrier type. These usually occur in association with the dry regions of the country where waters are clear. Nevertheless, even in these dry regions there are three places that have natural sediment inputs and restrict reef settlement (Punta Martín García in Barahona, Punta Salinas in Peravia, and El Morro in Montecristi).
French Martinique
Martinique, like Guadeloupe, is an overseas territory of France. Reefs are absent on the leeward northern, northwest and west coasts, because the shelf is narrow and there is a high sediment load from the erosion of Mount Pelée. There are, however, some coral communities along this coastline. Similarly, there are no true reefs along the northeast coast, although south of Presqu’île de la Caravelle a barrier reef continues along the shore for about 25 kilometers. The lagoon behind this reef is up to 30 meters deep in places and there are extensive seagrass communities. Fringing reefs have developed along the coast behind the barrier reef. Algae, including Sargassum, Turbinaria and Dictyota, have proliferated on the reefs of Martinique since the Diadema die-off. Eutrophication from the city of Fort-de-France may be combining with the lack of grazing organisms in maintaining this situation. Overfishing is a problem, with about 900 registered fishers in 1997, but many others operating. There were an estimated 50 000 wire-mesh fish traps around the island in 2000.
Grenada
Grenada is the most southerly of the Lesser Antilles, and the country also governs the southernmost islands of the Grenadines. There are some fringing and patch reefs around all the coasts of Grenada itself, although the total area of reef is not great. Off the eastern coasts of Carriacou and Petit Martinique relatively large bank barrier reefs have been formed. Many of the shallow reefs were reported to have become overgrown with algae during the 1980s, probably linked to the Diadema die-off, but possibly exacerbated by sewage and agrochemical pollution and increased sedimentation.
Haiti
One of the poorest countries in the Western Hemisphere, Haiti has been plagued by political violence for most of its history. Over three decades of dictatorship followed by military rule ended in 1990 when Jean-Bertrand ARISTIDE was elected president. Most of his term was usurped by a military takeover, but he was able to return to office in 1994 and oversee the installation of a close associate to the presidency in 1996. ARISTIDE won a second term as president in 2000, and took office early in 2001. However, a political crisis stemming from fraudulent legislative elections in 2000 has not yet been resolved.
Jamaica
Jamaica is the third largest island in the Greater Antilles and is located in the center of the Caribbean Sea. Cuba, 150 kilometers north, moderates the effects of the northeast trade winds on the fringing reefs of the north coast, which grow on a narrow shelf. Patchy reef formations on the south coast, punctuated by rivers and sediment slopes, grow on a wider shelf extending up to 20 kilometers offshore. Reefs and corals also grow on nine offshore banks, notably at the Pedro Cays, 70 kilometers south, and the Morant Cays, 50 kilometers to the southeast. Coral cover on the mainland fringing reefs is low, although this was not always the case. Cretaceous basement rocks are covered by Tertiary limestone, and on the north coast by Pleistocene reef deposits. Past changes in sea level have created terraces above and below present sea level to form raised or drowned cliffs. There are two wet seasons, in October and May, and two dry seasons. The water temperature on the north coast ranges from 26 to 30°C. The weather, particularly on the north coast, is dominated by the northeast trade winds, occasionally interrupted by cold fronts from North America in winter. Two of the most severe hurricanes on record, Allen and Gilbert, hit Jamaica in the 1980s, with significant impacts on the coral reefs.
Puerto Rico
Coral reefs are discontinuous around the main island of Puerto Rico, and most abundant along the east, south and west coasts. The offshore islands are more continuously fringed by reefs. Coral cover is highly varied, and the island ../../includes some of the best developed and most diverse coral reefs in the US Caribbean territories. As elsewhere, coral disease has had a significant impact on the total coral cover. The Diadema die-off was also considerable here, but numbers are now reported to be increasing. Coral bleaching in the late 1980s caused significant mortality, and a major bleaching event was also observed in 1998, though little associated mortality appears to have occurred.
St. Kitts and Nevis
This small independent state consists of two volcanic islands with steep mountainous slopes. There are fringing reefs along much of the coastline, and a number of deeper submerged reef structures. There is little published information about these reefs. Tourism is an important industry and there are now a number of dive operators.
St. Lucia
St. Lucia is a high volcanic island. Coral reefs are generally poorly developed, often only forming a thin veneer over the underlying volcanic substrates. The best developed reefs are in the south and east, although the best studied and most heavily utilized coral communities occur along the west coast. Certain reefs around Soufriere showed up to 50 percent live coral cover, but these sites were strongly impacted by Hurricane Lenny in 1999, which brought strong wave action on the leeward coast. Fishing is a very important activity around the island and overexploitation is a problem.
St. Vincent and the Grenadines
St. Vincent is a relatively young volcanic island. To the north, Mount Soufriere most recently erupted in 1979. The relatively young coastline, together with new volcanic sediments, have prevented the development of extensive reefs. There are no reef developments around the north and east coasts, and only a few coral communities are found on rocky headlands along the west coast. Small areas of fringing reefs occur on the south and southeast coasts. Running south from the main island is the chain of the Grenadines, where there are considerable areas of reef. Large bank barrier reef complexes have developed on the windward side of some islands. Among the best developed reefs are those around the small islands of the Tobago Cays. Each island has a fringing reef, the larger Horseshoe Reef encircles them to the east, while beyond this there is the larger World’s End Reef. The reefs of St. Vincent, and particularly the Grenadines, support important fishing and tourism, while large numbers of yachts visit these waters. The Tobago Cays are particularly important, but their condition has deteriorated recently because of storm damage, white band disease, physical damage from fishing gear and boat anchors, and pollution from visiting yachts.
Trinidad and Tobago
The large island of Trinidad and the nearby Tobago lie well south of the chain of the Lesser Antilles, on the continental shelf of South America. Reef development around Trinidad is severely restricted. The Orinoco River lies to the south and discharges huge volumes of sediment into the sea, creating turbid conditions which predominate along the south and east coastlines of the island. The western coastline faces the Gulf of Paria which, along with high levels of sediments, has near estuarine conditions arising from the high freshwater inputs and semi-enclosed nature of this gulf. There are small, low diversity coral communities in places on the north shore. Tobago lies close to the edge of the continental shelf, and here reef development is much better, with a number of fringing reefs, particularly on the north shore and in the southwest. Tobago has a considerable tourism industry, and the impacts of tourism have undoubtedly led to the degradation of some coastal reefs.
UK Anguilla
Anguilla is an overseas territory of the UK, and consists of a small carbonate island together with a number of smaller offshore cays. Fringing reefs are widespread, particularly on the south coast, and there are other reefs on the offshore cays. Anguilla has suffered fewer impacts than most other islands in the region. With no rivers there is little pointsource runoff, and although tourism development has been significant, it has had little direct impact. Dog Island, some distance off to the northwest, has reefs which are among the least impacted and visitors are actively discouraged. Plans to establish a satellite launching pad on the small island of Sombrero have recently been overturned, largely due to environmental concerns. It harbors an important bird colony, and its surrounding reefs are considered important, although they remain poorly documented.
UK Bermuda
Bermuda is an isolated group of 150 limestone islands in the Sargasso Sea area of the Western North Atlantic Ocean more than 1 000 kilometers from continental USA. Most of the land area is represented by five islands which are joined together by causeways. These islands are the high points of the Bermuda Platform – the nearby Plantagenet and Challenger Banks rise to 50 meters below sea level. Together the three banks crown the Bermuda Rise, a midplate hotspot of similar origin to Hawai‘i, although geologically older. Water in excess of 8 000 meters depth occurs just 6 kilometers to the northwest of Bermuda, as the sides of the Bermuda Rise fall steeply to the ocean floor.
UK Cayman Islands
The Cayman Islands are Overseas Territories of the UK and consist of three islands: Grand Cayman, Cayman Brac and Little Cayman. All are very low-lying, with a maximum elevation of only 42 meters. Jamaica and the Cayman Islands are situated on either side of the Oriente Transform Fault, which also separates the south coast of Cuba from Jamaica. The Cayman Trough, to the east of Jamaica and the southeast of Grand Cayman, is actively spreading at the mid-Cayman Rise. Weather patterns in the Caymans are broadly similar to those in Jamaica, but the eastern islands are generally drier than Grand Cayman.
UK Montserrat
This small island – an overseas territory of the UK – is mountainous and ../../includes considerable forest cover. Since 1995 however, the Soufriere Hills volcano has been active almost continuously, with major pyroclastic flows into the sea. Small scattered reefs and coral communities were originally described along much of the coastline, but it seems likely that they have been severely impacted by the massive inputs of sediment, and possibly chemical influences, associated with volcanic activity. Most of the island’s people have now been evacuated and the capital Plymouth was itself destroyed in 1997.
UK Turks and Caicos
The Turks and Caicos Islands (TCI) are located in the Atlantic Ocean between 21o 00’ and 21o 60’ North Latitude and between 71o 00’ and 71o 30’ West Longitude. These islands are part of the United Kingdom’s Overseas Territories. There are eight coraline islands and 40 small cays providing a total land area of about 166 square miles. The total population is estimated at about 23,000 persons, with about 73% of the population residing on one island, Providenciales (37.5 square miles in area).
. UK Virgin Islands
Coral reefs are widespread throughout the British Virgin Islands, including fringing reefs close to most islands, patch reefs in offshore areas, and a long barrier-type structure, Horseshoe Reef, extending to the southeast of Anegada. As with the US Virgin Islands, the reefs have been severely impacted by the passage of several hurricanes in recent years and, although not all areas were equally affected, some sites lost up to 100 percent of their live coral cover. There are now reports of a partial recovery in most places. The reefs have also suffered from coral disease and from the 1998 bleaching event. Although less well studied, it can generally be assumed that many of these impacts have had consequences similar to those in the nearby US Virgin Islands
US Virgin Islands
Coral reefs are widespread around all of the main islands. These are mostly fringing reefs, but there is a small barrier reef off St. Croix, and there are a number of offshore patch reefs and bank structures.Nowhere else in the Caribbean have the combined effects of hurricanes and disease on coral reef population structure been more pronounced than in the US Virgin Islands. In 1976 live coral cover on the fore reef at Buck Island, dominated by Acropora palmata, was 85 percent. Since then, eight hurricanes have caused serious physical damage to these reefs. Hurricane Hugo, in 1989, was undoubtedly the most severe, but in 1995 Hurricanes Luis and Marilyn hit the islands within a ten-day period and caused extensive damage in some areas.
Information provided by ICLARM - The World Fish Center, with support from the International Coral Reef Action Network (ICRAN). ReefBase: Oliver, J. and M. Noordeloos. Editors. 2002. ReefBase: A Global Information System on Coral Reefs.
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