Biological diversity in the Caribbean Islands

Published: August 22, 2008, 4:54 pm

Updated: April 22, 2011, 4:04 pm

Topics:

Conservation Biology (main) Biogeography (main) Ecoregions (main) Biodiversity (main) Ecology (main) Biomes (main) Geography (main)

Biological diversity in the Caribbean islands is characterised by species richness spanning a number of distinct islands.The Caribbean Islands hotspot consists mainly of three large groups of islands between North and South America: the Bahamas, the Lesser Antilles, and the Greater Antilles (Puerto Rico, Jamaica, Cuba, and Hispaniola, which includes the Dominican Republic and Haiti). Politically, the Caribbean (sometimes called the West Indies) comprises 12 independent nations and several French, British, U.S. and Dutch jurisdictions. While the hotspot spans more than four million square kilometres of ocean (Seas of the world), it covers roughly 230,000 km² of land area, with the four islands of Cuba, Hispaniola, Jamaica and Puerto Rico making up around 90 percent of land area.

Caribbean Islands. (Source: CI/CABS)

Elevations in the Caribbean Islands range from over 3000 metres (m) (the formerly glaciated summit of Pico Duarte) to a desert depression 40 m below sea level, both on Hispaniola. Low-lying islands tend to be semiarid, and most were originally dominated by dry evergreen bushland and thicket, with savanna, cactus shrub and spiny shrub occurring on parts of Barbuda, Jamaica, and Puerto Rico, where the average rainfall at low elevations is only 300 to 600 millimetres [mm] per year.

On the other hand, wetter environments occur where trade winds encounter the higher Caribbean mountains, giving rise to a variety of moist tropical forest types including marsh forest, seasonal forest, montane forest, and elfin woodland. In moister areas, around lagoons and river mouths, permanent brackish and freshwater swamps give way to extensive mangrove forests.

Unique and Threatened Biodiversity

Plants

Plant diversity and endemism are very high in the Caribbean Islands, with an estimated 13,000 species, including more than 6500 single-island endemics. Endemism at higher levels is also exceptional, with 205 plant genera and one plant family, the Goetziaceae, found nowhere else on Earth.

Endemism is also significant at the island level; about one-quarter of the region's vascular flora is restricted to a single island – Cuba. Cuba is by far the most biologically important island in the region in terms of biodiversity, particularly for plant diversity, with more than 6500 vascular plants, of which about half are endemic. The largest island in the Antillean chain, Cuba accounts for about 48 percent of the land area of the entire hotspot and is home to more than half of the region's endemic plants, making it a top conservation priority for the Caribbean; however, considerable destruction of habitat has occurred in Cuba, beginning in the early 1960s. Of the endemic genera in the hotspot, about 120 are confined to single islands.

Caribbean mahogany (Swietenia mahagoni, EN), a cousin of the big-leaf mahogany (Swietenia macrophylla, VU) of South and Central America, has been exploited heavily throughout the region for timber. The species has been extirpated from portions of its range, and remaining old growth stands have been plundered. Other economically valuable timber species in the Caribbean Islands include walnut (Juglans jamaicensis, VU), West Indian ebony (Brya ebenus), and poui (Tabebuia heterophylla).

Vertebrates

Birds

There are more than 600 bird species in the Caribbean Islands, of which roughly 160 are endemic, some restricted to small areas on single islands. A remarkable 36 genera are endemic to the region, as well as two endemic families: the palmchat (Dulus dominicus) of the family Dulidae and the todies (family Todidae). BirdLife International recognizes six primary and two secondary Endemic Bird Areas (EBAs) within the Caribbean Islands hotspot, a testament to the diversity and island-specific endemism in this region. Forty-eight species endemic to the hotspot are threatened with extinction, including the Puerto Rican nightjar (Caprimulgus noctitherus, CR), Zapata rail (Cyanolimnas cerverai, EN), Zapata wren (Ferminia cerverai, EN), and Grenada dove (Leptotila wellsi, CR).

Taxonomic Group	Species	Endemic Species	Percent Endemism
Plants	13,000	6,550	50.4
Mammals	89	41	46.1
Birds	604	163	27.0
Reptiles	502	469	93.4
Amphibians	170	170	100.0
Freshwater Fishes	161	65	4

Thirteen bird species have already become extinct within this hotspot; six of those species were of the genus Ara, the large and brightly-feathered macaws. The Cuban macaw (Ara tricolor), the last of the six to disappear, was hunted to extinction for food and the pet trade during the second half of the 18th century. The spectacular ivory-billed woodpecker (Campephilus principalis), which once ranged throughout Cuba and the bottomlands of the southeastern United States, has not been recorded in Cuba since 1987. However, recent reports of the species from Arkansas, although controversial, give renewed hope for its possible persistence on Cuba, and it is still listed as Critically Endangered rather than as officially Extinct.

Among the most important bird symbols for conservation in the Caribbean are the parrots, including the St. Vincent parrot (Amazona guildingii, VU), the St. Lucia parrot (Amazona versicolor, VU), and the imperial parrot (Amazona imperialis, EN) of Dominica. All three species are strikingly coloured and rely on undisturbed forest for survival. Another remarkable species is the bee hummingbird (Mellisuga helenae) of Cuba. This tiny bird, which is only 5.5 centimeters (cm) long and weighs 1.95 grams, is the world's smallest bird.

Mammals

The Caribbean Islands have nearly 90 mammal species, of which more than 40 are endemic. This includes two endemic rodent families: Solenodontidae and Capromyidae. The family Solenodontidae includes two surviving species, the Cuban solenodon (Solenodon cubanus, EN), and Hispaniolan solenodon (S. paradoxus, EN), which are rare giant shrews threatened by human exploitation and alien species, including mongooses, feral cats, rats and dogs. The Capromyidae includes 20 species of rodents, known locally as hutias, which are prized for their meat and threatened by hunting, habitat loss and invasive species. The region hosts 15 endemic genera, including the fruit-eating bat genus Brachyphylla, with two species.

The West Indian manatee (Trichechus manatus, VU) is native to Cuba, Hispaniola, Puerto Rico and Jamaica. Worldwide, manatees are increasingly threatened by commercial fishing and boat-strike mortality. Another significant marine mammal species has already gone extinct. The Caribbean monk seal (Monachus tropicalis, EX), which was once widespread throughout the Caribbean, was hunted into oblivion, with the last individual collected in 1965. In total, 19 mammal species once endemic to the Caribbean are recently extinct (since 1500 AD), including four species of Nesophontes, relatives of the solenodons.

Reptiles

The Caribbean Islands are particularly rich in reptiles, with over 500 reptile species, almost 470 of which (94 percent) are endemic. The diversity here includes several large evolutionary radiations of lizards, such as the anoles (Anolis; 154 species, 150 endemic) with their colorful dewlaps used in displays; dwarf geckos (Sphaerodactylus; 86 species, 82 endemic); and curly tails (Leiocephalus; 23 species, all endemic) that hold their tails in a coil as they run. This lizard fauna includes the smallest lizards in the world, Sphaerodactylus ariasae from the Dominican Republic and S. parthenopion from the U.S. Virgin Islands.

The West Indies is also home to the world's smallest snake, Leptotyphlops bilineata, which could slither through a pencil if the lead were removed. Leptotyphlops is one of a number of major radiations of snakes in this hotspot, including the large boas (Epicrates, nine species); a genus of boldly patterned snakes that change colors (Tropidophis; 26 species, all endemic); and fastmoving racers (Alsophis; 13 species, all endemic). The Aruba island rattlesnake (Crotalus unicolor, CR), endemic to Aruba, is the most threatened rattlesnake in the world. While there are fewer than 250 individuals left in the wild, the snake has been the focus of significant and successful conservation, public awareness, and research programs. A total of six snake genera are endemic to the hotspot.

Also included in the reptile fauna are nine species of rock iguana from the genus Cyclura, all threatened, including some that measure more than one meter in length. The Jamaican iguana (Cyclura collei, CR) was thought to be extinct until a small population of about 200 individuals was rediscovered in 1990 in the Hellshire Hills of Jamaica. The Cuban crocodile (Crocodylus rhombifer, CR) was once found all over Cuba and in the Cayman Islands and Bahamas, but is now found only in the Zapata swamp; and it is the most threatened species of New World crocodilians.

Amphibians

The Caribbean is also a center of amphibian endemism, with all of the roughly 170 native species of amphibians from four families of frogs (the Bufonidae, Dendrobatidae, Hylidae, and Leptodactylidae) endemic to the hotspot. All but a few species are endemic to single islands.

More than 80 percent of all amphibians found in the Caribbean belong to the large genus Eleutherodactylus, forest frogs that lay eggs on land and hatch into miniature adults with no tadpole stage. One Cuban species (E. iberia, CR) is the smallest tetrapod in the Northern Hemisphere, with a length of only 10 millimetres (mm), while a golden-colored species in Puerto Rico, possibly Extinct, is one of only a few species of frogs in the world known to be live-bearing. One of the largest tree frogs (Hylidae) in the world, the Jamaican snoring frog (Osteopilus crucialis, EN), has a length of about 120 mm and occurs in Jamaica, where males of this declining species make a loud snoring call from within giant, hollow trees.

Among the most interesting [[amphibian]s] found in this hotspot is the Mountain chicken (Leptodactylus fallax, CR), the second largest frog in the Western Hemisphere. The frog gets its name from the fact that it is a favorite culinary treat on some islands; it has been rapidly declining in numbers due to human consumption, habitat destruction and disease.

des

Freshwater Fishes

The Caribbean Islands have more than 160 species of freshwater fish, about 65 of which are endemic to one or a few islands, and many of these to just a single lake or springhead. As in other island hotspots, there are two distinct groups of freshwater fishes in the Caribbean: on smaller and younger islands, most fish are species that are widespread in marine waters but also enter freshwater to some degree, while on the larger and older islands of the Greater Antilles, there are several groups that occupy inland waters, including gars, killifishes, silversides and cichlids.

Human Impacts

Found only on the island of Cuba, the Cuban crocodile (Crocodylus rhombifer, EN) is threatened due to hunting and habitat encroachment by humans and competition with caimans (Caiman crocodilus), a crocodilian species from Central and South America that was introduced to the island. These juvenile Cuban crocodiles were photographed at a crocodile farm in the Zapata swamp region. (Source: Photograph by Cristina Mittemeier)

Humans arrived in the Caribbean Basin about 4000 years ago. However, it is only in the last 500 years that significant environmental degradation (Habitat destruction) has occurred, beginning with the arrival of the first Europeans on Hispaniola in 1492 AD. The initial wave of forest clearing began in the early 1500s, for sugar cane plantations. Sugar cane, which has led to widespread deforestation throughout the region, is still the Caribbean's most important crop. Another major impact of the arrival of human settlers has been the introduction of alien species, which is the biggest threat to biodiversity in this hotspot. Even before the arrival of Europeans, people in the Caribbean were transporting species that they used for food from one island to another. Early examples include the agouti, a land tortoise, and even the white-tailed deer (Odocoileus virginianus). The small Asian mongoose (Herpestes javanicus), which was first introduced in 1872 to control rodents and poisonous snakes, has devastated native populations of reptiles and [[amphibian]s] and led to the extinction of dozens of species.

Rats, cats, dogs, goats, donkeys, monkeys, tilapia, and even trout also pose a serious threat to native fauna. Natural resources and ecosystems have been devastated on some islands. For example, no less than 92 percent of amphibian species found on Haiti are threatened with extinction (in fact, the top five countries in the world, with the highest percentage of threatened amphibians are all Caribbean: Haiti, Dominican Republic, Cuba, Jamaica, and Puerto Rico). Agriculture remains a serious threat in parts of the hotspot, with cacao, coffee, and tobacco plantations threatening remaining large tracts of pristine forest. Mining for bauxite, sand, and gravel, as well as the production of charcoal from natural vegetation to meet energy needs also pose threats to the hotspot's native flora and fauna.

Tourism development has put pressure on natural ecosystems on some islands, particularly in the alteration of local landscapes with non-native vegetation, golf courses, roads, and tourist infrastructure and facilities. However, responsible tourism has been a positive force for conservation. A meeting held in April 2003, "Making Biodiversity Work for your Travel Business: Increasing Profitability while Protecting the Environment", brought together approximately 100 leaders from Caribbean tourism businesses, academia, government and civil society organizations to share experiences and commit to further actions that will not only protect biodiversity but also maintain the Caribbean's competitive edge as a premier tourism destination.Today, no more than 23,000 km², 10 percent of the original vegetation, remains in a pristine state in the Caribbean Islands Hotspot. While less than 15 percent of Cuba's forests remain intact, they are the largest remaining tracts of forest in the Caribbean.

Conservation Action and Protected Areas

About 30,000 km², or 13 percent of the land area of this hotspot, is officially protected, but many of these protected areas are far from pristine. Just over half of the protected land area, totaling a little over 16,000 km² is in IUCN categories I to IV, which afford greater protection. In general, there is a great need for much better management, monitoring, and enforcement of protected areas throughout the Caribbean. Cuba has about 15 percent of its land area in conservation units, including the 300-km² Zapata Swamp. Dominica has a little over 20 percent of its territory designated for protection, while the Dominican Republic reports about 15 percent. However, many of these reserves lack formal management plans, and are too small to effectively conserve biodiversity. In other countries, protected areas are effectively non-existent, as is the case in Haiti and Grenada, which both have less than 1.7 percent of their area protected.

In general, the Caribbean Islands emerge as top priority for the expansion of the global protected areas network. A wide variety of local organizations promote conservation efforts in the Caribbean. For example, Grupo Jaragua, a group of citizens and scientists in the Dominican Republic, helps support and manage Jaragua National Park, one of the largest land-and-sea parks in the hotspot. In Haiti, the Foundation for the Protection of Marine Biodiversity works with both fishers and the government to promote sustainable use of the country's living marine resources. A non-governmental organization, the Bahamas National Trust, manages the Bahamian national park system, which is being expanded to cover twenty percent of the country's territorial seas.

On Bonaire, the National Parks Foundation actively manages the Bonaire Marine Park, which is widely recognized as one of the most effective marine reserves inside the hotspot. Its counterpart on St. Eustacius, an island with only 2,000 people, provides technical backstopping for programs ranging from sea turtle tagging and monitoring of the island's pristine reefs to the development of nature trails that reach the elfin forest at the island's volcanic summit.The prospects for biodiversity conservation in the Caribbean Islands have been enhanced by the development of partnerships between major industries, such as tourism, and the governmental and private organizations that are promoting conservation on the ground. The Protocol Concerning Specially Protected Areas and Wildlife (SPAW), which came into force in 2000, was created at the initiative of the Caribbean countries to provide region-wide standards and mechanisms for harmonizing conservation efforts across the region.

Notes The initial version of this article was based on contributions from Michael Leonard Smith, S. Blair Hedges, William Buck, Arlo Hemphill, Sixto Inchaustegui, Michael I. Ivie, Don Martina, Michael Maunder, and Javier Francisco Ortega. For a complete list of all contributors to the Biodiversity Hotspot program, see Biodiversity Hotspot Site Credits (Biological diversity in the Caribbean Islands) .

Further Reading

• Beard, J.S. 1949. Natural Vegetation of the Windward and Leeward Islands. Oxford: Clarendon Press.
• Beard, J.S. 1955. The classification of tropical American vegetation types. Ecology, 36:89-100.
• Borhidi, A. 1991. Phytogeography and Vegetation Ecology of Cuba. Budapest: Akadémiai Kiadó. ISBN: 9630569566
• Capote, R.P., Berazaín, R. & Leiva, A. 1989. Cuba. In D.G. Campbell & D. Hammond. (Eds.), Floristic Inventory of Tropical Countries: The Status of Plant Systematics, Collections, and Vegetation, plus Recommendations for the Future. pp. 315-335. New York: The New York Botanical Garden. ISBN: 0893273333
• Christ, C., Hillel, O., Matus, S. & Sweeting, J. 2003. Tourism and Biodiversity: Mapping Tourism’s Global Footprint. Washington, D.C. and Paris, France: Conservation International & United Nations Environment Programme.
• Delgadillo, C., Bello, B. & Cardenas, A. 1995. LATMOSS: A catalogue of neotropical mosses. Monographs in Systematic Botany. Missouri Botanical Garden, 56:1-191. ISBN: 0915279355
• Estrada, A.R. & Hedges, S.B. 1996. At the lower size limit in tetrapods: A new diminutive frog from Cuba (Leptodactylidae: Eleutherodactylus). Copeia, 4:852-859.
• Graham, A., 2003. Historical phytogeography of the Greater Antilles. Brittonia, 55(4):357-383.
• Hedges, S.B. 1993. Global amphibian declines: A perspective from the Caribbean. Biodiversity and Conservation, 2:290-303.
• Hedges, S. B. 1996. The origin of West Indian amphibians and reptiles. In R. Powell & R.W. Henderson. (Eds.), Contributions to West Indian Herpetology: A Tribute to Albert Schwartz. Society for the Study of Amphibians and Reptiles. ISBN: 0916984370
• Hedges, S. B. 1999. Distribution patterns of amphibians in the West Indies. In Duellman, W. E. (Ed.), Regional Patterns of Amphibian Distribution: A Global Perspective. pp. 211-254. Baltimore: Johns Hopkins University Press. ISBN: 0801861152
• Hedges, S. B. 2001. Caribbean Biogeography: An Overview. In C. A. Woods & F. E. Sergile. (Eds.), Biogeography of the West Indies: Patterns and Perspectives. Boca Raton, Florida: CRC Press.
• Hedges, S. B. 2004. Caribherp: West Indian Amphibians and Reptiles.
• Harcourt, C.S. & Sayer, J.A. 1996. The Conservation Atlas of Tropical Forests: The Americas. The World Conservation Union. New York: Simon & Schuster. ISBN: 0133408868
• Harris, D.R. 1965. Plants, Animals, and Man in the Outer Leeward Islands, West Indies: An Ecological Study of Antigua, Barbuda, and Anguilla. Berkeley & Los Angeles: University of California Press.
• Hoagland, D.B., Horst, G.R. & Kilpatrick, C.W. 1989. Biogeography and population biology of the mongoose in the Caribbean basin. In C.A. Woods. (Ed.), Biogeography of the Caribbean Basin Past, Present, and Future. pp. 611-634. Gainesville, Florida: Sandhill Crane Press Inc.
• Lammertink, M. & Estrada, A.R. 1995. Status of the ivory-billed woodpecker Campephilus principalis in Cuba: Almost certainly extinct. Bird Conservation International, 5:53-60.
• Rodrigues, A. S. L., Andelman, S. J., Bakarr, M. I., Boitani, L., Brooks, T. M., Cowling, R. M., Fishpool, L. D. C., Fonseca, G. A. B., Gaston, K. J., Hoffmann, M., Long, J., Marquet, P. A., Pilgrim, J. D., Pressey, R. L., Schipper, J., Sechrest, W., Stuart, S. N., Underhill, L. G., Waller, R. W., Watts, M. E. J. & Xie, Y. 2003. Global gap analysis: Towards a representative network of protected areas. In Advances in Applied Biodiversity Science. Washington, DC: Conservation International.
• Schwartz, A. & Henderson, R.W. 1991. Amphibians and Reptiles of the West Indies: Descriptions, Distributions, and Natural History. Gainesville, Florida: University of Florida Press. ISBN: 0813010497
• Thorbjarnarson, J., Messel, H., King, F.W. & Ross, J.P. (Eds.). 1992. Crocodiles: An Action Plan for their Conservation. Gland, Switzerland: IUCN/SSC Crocodile Specialist Group. ISBN: 2831700604

Disclaimer: This article contains certain information that was originally published by Conservation International. Topic editors and authors for the Encyclopedia of Earth have edited that content and added new information. The use of information from the Conservation International should not be construed as support for or endorsement by that organization for any new information added by EoE personnel, or for any editing of the original content.

Citation

International, C. (2011). Biological diversity in the Caribbean Islands. Retrieved from http://editors.eol.org/eoearth/wiki/Biological_diversity_in_the_Caribbean_Islands