Species diversity in the Bahamian ccorcgion is different to other parts of the Caribbean such as along the coasts of south and central America. Absent arc manatees, saltwater crocodiles, and many of the species associated with large fluvial estuaries. Acroporid corals (Acropora palmate) is particularly abundant on shallow fringing reef stmcturcs and Montastraea wmularis is the major reef builder on the deeper tore reefs. Extensive hardbottom algal communities characterize large areas of the exposed southern banks whereas soft bottom conmmnitics occur in the island sheltered banks. Reef tish communities in much of the region contain largely intact predator assemblages, including large numbers of Nassau groupers (Epinepllelous striates) with a very high number of intact spawning aggregation sites. A recent rapid ecological assessment of this area found that it harbors some of the largest populations of bonctish in the world. Sea tm1lcs (mainly greens and loggerheads) forage over much of this area during juvenile lite stages with some of the highest densities ever observed. Seabirds occupy many of the uninhabited offshore cays particularly in areas of higher productivity such as Cay Sal Barllc. The largest breeding ground tor Atlantic humpback whales occur on the banks at the southern end of this ecorcgion. Pressure on the marine resources continues to be comparatively light due to the fairly low population densities and oppo11unitics in the growing tourism industries. Tire Greater Autil/es arc the large, tectonically active and mountainous islands of Cuba, Jamaica, Hispaniola, and Puerto Rico. The sheer size and height of these island masses arc enough to create localized daily adiabatic winds that can override the regional easterly trade winds and produce localized climate and rainfall. Watersheds are small to moderate in size producing substantial fluvial discharge and nutrients into the coastal zones. Tectonic activity in this area of the Caribbean remains high because of the underlying plate boundary and tectonic uplift continues today. Estuaries tend to occur as large tectonic shaped inlets (perpendicular to the coastline) that may be highly stratified and deep depending on the amount of fluvial discharge. Except for the north coasts of Cuba and Puerto Rico, tides arc typically quite low (-25 em) tor much of the rest of the ccorcgion. The marine habitat beta diversity in the Greater Antilles is higher than in the eastern Caribbean or Bahamian ccoregions because of the substantial gradients around the islands with respect to exposure and productivity. Fringing reefs arc most common with larger barriers forming along the wider shelf areas south as found along the south coast of Cuba. There arc several banks within this ccorcgion including Pedro Bank and several otT the south coast of Cuba but the water depths arc greater than for banks in the Bahamian ccorcgion. Marine species diversity is high but larger megafauna have been severely impacted by human activity over the past several hundreds of years. Small populations of manatees and saltwater crocodiles still occur on all of the Antilles but arc restricted to a very small portion of their original distribution. Similarly, sea turtle populations and nesting occurrences have also been dramatically reduced from what was observed several hundreds of years ago but still occurs on all ofthe islands in small numbers. Coral reef species include all ofthc known sclcractinian corals that exist in the western tropical Atlantic. With a combined population of over 25 million on these islands, the density of people living on the Greater Antillean islands is some of the highest in the world. Severe ovcrtishing has depleted reef tish stocks and altered the trophic structure of the entire coastal zone. Tire Lesser Antilles or Eastern Caribbean is a half-moon shaped string of over 60 islands stretching 600 miles tram the U.S. and British Virgin Islands to Grenada. This region of the Caribbean is a back-arc basin and characterized by small island sizes many of volcanic origins associated with the adjacent plate boundary. The Virgin islands (U.S. and British) found at the northern boundary of this ecoregion arc geologically more similar to the Greater Antilles but have been grouped into the Eastern Caribbean because of their small island size and easterly exposure to the Atlantic swells. The small size of the islands minimized localized climate and rainfall effects and produces very few large freshwater rivers or estuaries. 4 -7-