BIOLOGICAL IMPORTANCE OF THE CARIBBEAN The Caribbean Islands Hotspot comprises 30 nations and territories, each characterized by unique and wide-ranging biodiversity and culture. It is one of the world’s greatest centers of endemic biodiversity as a result of the region’s geography and climate: an archipelago of habitat-rich tropical and semi-tropical islands tenuously connected to surrounding continents.
Habitats and Ecosystems Geography, climate and the large geographic expanse of the Caribbean Islands Hotspot has resulted in a diverse range of habitats and ecosystems, which in turn support high levels of species richness. Although 14 Holdridge life zones and 16 WWF ecoregions have been defined in the hotspot, there are four major terrestrial forest types, the distribution and biodiversity characteristics of which are described below.
Tropical/ Subtropical Moist Broadleaf Forests occur mainly in lowland areas influenced by north-easterly or north-westerly winds, and on windward mountain slopes, such as the northern part of eastern Cuba, northern Jamaica, eastern Hispaniola, northern Puerto Rico and small patches in the Lesser Antilles.
Tropical / Subtropical Dry Broadleaf Forests are found in the Bahamas, Cayman Islands, Cuba, Hispaniola, Jamaica, the Lesser Antilles and Puerto Rico. The dry forest life zone tends to be favored for human habitation, largely because of relatively productive soils and reasonably comfortable climate. For this reason, few dry forests remain undisturbed.
Tropical / Subtropical Coniferous Forests (both lowlands and montane) are found in the Bahamas, Turks and Caicos, Cuba and Hispaniola where they are often threatened by timber extraction and frequent man-made fires that change their age structure and density.
Shrublands and Xeric Scrub occurs in areas of rain shadows created by mountains, and also in the more arid climate of the southern Caribbean (e.g. Aruba, Bonaire and Curaçao). Xeric shrublands and cactus scrub are found where suitable conditions occur throughout the Lesser Antilles and on Cuba.
The Caribbean Islands Hotspot also supports important freshwater habitats, including large lowland rivers, montane rivers and streams, lakes, wetlands and underground karst networks. In addition to providing habitat for many important, unique and migratory animals and plants, these freshwater sites provide clean water, food and many services to local communities. These services are especially important as the small islands of the insular Caribbean are surrounded by salt water, and rely greatly on limited, land-based freshwater from functional ecosystems. With the majority of Caribbean people living close to the shoreline, coastal ecosystems, including mangroves, beaches, lagoons and cays, are essential not only for biodiversity, but for buffering coastal communities from the effects of storms, providing a basis for recreational and tourism industries, as well as nursery habitat for commercial species.
Species Diversity, Endemicity and Global Threat Status The Caribbean Islands Hotspot supports a wealth of biodiversity within its diverse terrestrial ecosystems, with a high proportion of endemicity making the region biologically unique. It includes about 11,000 plant species, of which 72 percent are endemics. For vertebrates, high proportions of endemic species characterize the herpetofauna (100 percent of 189 amphibian species and 95 percent of 520 reptile species), likely due to their low dispersal rates, in contrast to
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