The wet forests of Hispaniola maintain exceptionally distinct insular flora and fauna, with many unique species, genera and families that have maintained various relict taxons. Many of the relictual species that survive in these forests are extinct on the nearby continents. The status of conservation of this ecoregion is endangered in that it has gone from representing more than half of the island’s original vegetation to less than 15% at present. The major threats include illegal forestry operations, migratory agricultural expansion, gathering of firewood, grazing and illegal hunting.
Location and General Description
These wet forests originally occupied more than half (~60%) of the original vegetation on the island of Hispaniola, from the lowlands particularly on the eastern coast of the island to the valleys, plateaus, slopes and foothills of the many mountain ranges, up to an altitude of about 2,100 meters. In the Dominican Republic, moist forest frequently occur covering most of the eastern half of the country all along these shores till ending at the higher elevations of the mountains. Between the slopes of the eastern range and along the northern range in Haiti, the moist forests continue across the entire island of Hispaniola only lacking distinct presence in the southern extension of the island. They also exist on most of the Tiburón peninsula, in southern Haiti.
In this ecoregion, ecological conditions are the result of a complicated climate system, influenced primarily by the presence of subtropical anticyclones, the direction of the trade winds that predominate for most of the year, as well as altitudinal conditions. The period of most frequent rainfall is from April to December, varying in intensity depending on the orographic effects to which the areas of these forests are subject. Average annual precipitation varies between 1,000 to 2,000 mm for the wet zones, to more than 4,000 mm per year in the rainforest zones. In open areas near the coast, average annual temperature is from 23° to 24°C. In higher areas or areas closer to the mountain ranges, average annual temperature is about 20ºC and in the highest zones there are frosts (temperatures below 0º C) at certain times of the year.
The topography of this ecoregion is also varied, ranging from flatlands to valleys to rugged land. Two principal edaphic facies are identified, on neutral or somewhat alkaline soil (calcareous) and on acid soil. This ecoregion is important because it lies in the island’s most important water catchment basins and because it controls runoff from rains and soil erosion. The main rivers of Hispanola Island are Yaqus del Norte and del Sur and the Rio Yuna of Dominican Repulic and the Artibonite of Haiti.
Moist forests are classified according to their altitude, from lowland to montane and the precipitation they receive, from wet to rainforest. The principal indicator species that help to identify this ecoregion in the lowlands are oak (Catalpa longissima), particularly in well-drained lands, and mahogany (Swietenia mahagoni). In places where the soil comes from calcareous rocks, royal palm is common (Roystonea hispaniolana). The vegetation of the small secondary stands consists primarily of species of "Juan Primero" (Simaruba glauca), "anón de majagua" (Lonchocarpus pentaphyllus) and "jagua" (Genipa americana). Other species are black olive, "guaraguao" or "grigrí" (Bucida buceras), West Indian lancewood or "yaya" (Oxandra lanceolata) and "amacey" (Tetragastris balsamifera). The species of isolated trees are primarily fustic (Chlorophora tinctoria), logwood or "campeche" (Haematoxylon campechianum), iris (Hippeastrum puniceum), "caracolí" (Pithecellobium glaucum), West Indian elm or "guácima" (Guazuma ulmifolia), "palo de leche" (Rauwolfia nitida), fiddleword or "penda" (Citharexylum fruticosum) and "córbano" (Pithecellobium berterianum).
The vegetation on the savannas (resulting from the degradation of the forest) and lands with superficial soils is characterized by the presence of trees such as the sandpaper tree or "peralejo" (Curatella americana), sea grape or "hojancha" (Coccoloba pubescens), Florida trema or "memiso" (Trema micrantha) and oak (Tabebuia spp.). The zones that have marginal earth and precipitation close to the dry subtropical forest are characterized by the presence of cashew or "cajuil" (Anacardium occidentale). In wetter forests, we find yellow olivier or "guaraguao" (Buchenavia capitata), and generally "sablito" (Didymopanax morototoni), "peralejo" or "madroño" (Byrsonima spicata) and "aguacatillo" (Alchornea latifolia). We also find myrtle laurelcherry, "membrillo" or "almendrito" (Prunus myrtifolia), "mara" or "baría" (Calophyllum brasiliense), "cocuyo" (Hirtella triandra), American muskwood or "cabirma" (Guarea guidonia), "palo de yagua" (Casearia arborea), locust (Hymenea courbaril), "balatá" (Manilkara domingensis) and sierra or "manacla" palm (Prestoea montana). Another common species is pine (Pinus occidentalis), particularly in lateritic soils. Rainforests, with greater precipitation, consist of trees covered by parasitic and epiphytic plants. The principal indicator species include arboreal ferns (Cyathea spp.) and orchids (Linociera spp.). At higher elevations, characteristic species are "temblón" or "palo de viento" (Didymopanax tremulu), ebony (Diospyros ebenaster), almond (Prunus occidentalis), Garrya fadyenii, Weinmannia pinnata, Oreopanax capitatum, and Brunellia comocladifolia, as well as "pino criollo" (Pinus occidentalis) and arboreal ferns (Cyathea spp.).
Despite their degradation, these wet forests still maintain an exceptionally diverse insular biota with many endemic regional and insular species belonging to a large number of taxons. These forests have been isolated from the contiguous continents and have thus maintained relict taxons. In the mountains of Selle-Bahoruco alone there are five endemic genera of plants. This ecoregion is found in the five most important centers of plant diversity and endemism on the island. In the Dominican Republic, these centers correspond to Los Haitises, with characteristic forests over karstic limestone (mogotes), more than 500 species of plants and about 30% insular endemisms. The central mountain range has a total of 1,500 plant species and about 25% insular endemisms in its lowland and mountain forests. The Sierra de Neiba with 350 plant species and 25% endemisms in its low mountain forests. In Haiti, these centers are found in the low mountain forests of Morne la Visite with 335 plant species and 30% insular endemisms and in the low mountain forests of Pic Macaya with 665 species and 30% endemisms. In Sierra de Bahoruco National Park alone 166 or 52% of the orchids existing in the country are represented, and 32 of these or 10% are species endemic to the mountains.
The fauna of this ecoregion is diverse and rich in endemisms, particularly birds. Some of the most characteristic are the Hispaniolan parrot (Amazona ventralis), the parakeet (Aratinga chloroptera), the Hispamiolan lizard cuckoo (Saurothera longirostris), the palm crow (Corvus palmarum), the American kestrel (Falco sparverius), the Vervain hummingbird (Mellisuga minima), the narrow-billed tody or "barrancolí" (Todus angustriostris). The stolid flycatcher or "manuelito" (Myiarchus stolidus), the endemic peewee or "maroita" (Contopus hispaniolensis), the rufous throated solitaire (Myadestes genibarbis), the woodpecker (Melanerpes striatus), the white necked crow (Corvus leucognaphalus), the palm chat (Dulus dominicus), declared the national bird of the Dominican Republic, the Hispaniolan trogon (Temnotrogon roseigaster), the ruddy quail dove (Geotrygon montana), the red-tailed hawk or "guaraguao" (Buteo jamaicensis), the white-winged warbler (Xeboligea montana), and the green tailed ground warbler (Microligea palusrtris), the antillean siskin (Carduelis dominicensis), the la Selle thrush (Turdus swalesi), the chat-tanager or "chirri de los Bahorucos" (Calyptophilus frugivorus),and white winged crossbills (Loxia leucoptera).
To be noted among the mammals are the hutia or agouti (Plagiodontia aedium) and the Haitian solenodon or "nez longue" (Solenodon paradoxus). There is also a great variety of amphibians and reptiles, as well as invertebrates. Due to the threats in the ecoregion, many of these species are endangered.
More than 90% of this ecoregion’s original habitat has been lost and there is at least one original habitat block larger than 500 km2, which makes up about 1% of the ecoregion. The degree of fragmentation is average because the fragments are somewhat grouped. The annual rate of habitat conversion during the period 1990-95, from intact to altered, was about 2.5% There is at least one protected area with an intact habitat block larger than 500 km2. The gaps in bio-geographical data on the ecoregion are sufficient to hamper protection and conservation efforts. The gaps in taxonomic data are not as large although greater knowledge is still needed. According to the Dominican Republic’s 1999 National Human Development Report, latifoliate cloud forest in this country covers 2.29 %, latifoliate forest 6.54%, and semi-wet latifoliate forest 4.25%, for a total of 13%. The forest situation of Haiti is an even greater concern in that only 1.44% of the total original forest coverage remains. Less than 200 km2 of unaltered rainforest remains in Haiti.
In the Dominican Republic, this ecoregion is protected in part in the Armando Bermúdez National Park (766 km2), the José del Carmen Ramírez National Park (764 km2), the Valle Nuevo Scientific Reserve (409 km2), Ébano Verde Scientific Reserve (23 km2), the Sierra de Neiba National Park (407 km2), the Sierra Bahoruco National Park (1.027 km2), the Mirador del Paraíso Scenic Route, the National Park of the East (433 km2) and Los Haitises National Park (208 km).
In Haiti, this ecoregion is only represented in parts of the Pic Macaya National Park (55 km2) and the La Visite National Park (20 km2).
Types and Severity of Threats
Illegal forestry operations and migratory agricultural expansion are a serious threat to the ecoregion. Other threats include the gathering of firewood, grazing, illegal hunting, contraband in endangered species and tourism in some areas.
Justification of Ecoregion Delineation
Justification and linework will be available by January 2002.
Additional information on this ecoregion
- For a shorter summary of this entry, see the WWF WildWorld profile of this ecoregion.
- To see the species that live in this ecoregion, including images and threat levels, see the WWF Wildfinder description of this ecoregion.
- World Wildlife Fund Homepage
- Caribbean Environmental Programme (CEP) 1996. Status of Protected Area Systems in the Wider Caribbean Region. CEP Technical Report No. 36
- CONATEF/FAO, 1991. Plan de acción Forestal para República Dominicana. Secretariado Técnico de la Presidencia, Comisión Nacional Técnica Forestal.
- CRIES, 1980. Land cover/use inventory for the Dominican Republic through visual interpretation of LandSat imagery. CRIES/USDA/AID/MSU.
- Davis, S., V. Heywood, Herrera-MacBryde, J. Villa-Lobos, and A. Hamilton, editors. 1997. Centres of plant diversity. A guide and strategy for their conservation. WWF and IUCN, Washington, DC.
- Dinerstein, E., D.M. Olson, et al. 1995. A Conservation Assessment of the Terrestrial Ecoregions of Latin America and the Caribbean. The World Bank in association with WWF, Washington, D.C.
- DIRENA (en prensa). Inventario de la vegetación y uso de la tierra en la República Dominicana. Departamento de Inventario de Recursos Naturales. SURENA/SEA.
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- FAO 1997. State of the World’s Forests 1997. Food and Agriculture Organization of the United Nations, Rome.
- García, R. 1994. Diversidad, endemismo y especies amenazadas en la flora de la Isla Española. En: Situación ambiental y situación de la Biodiversidad en la República Dominicana. Agenda Ambiental Dominicana, No.1. Santo Domingo.
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- STD (Science and Technology Division) 1979. Draft environmental report on Haiti. Library of Congress and US Man and Biosphere Secretariat, Washington, D.C.
- Strauss V., 2000. Wood has become a scarce commodity. Island beat: News from the Environmental Frontline of the Caribbean. http://www.panosinst.org/Island/IB1e.htm
- Tasaico, H. 1967. Mapa ecológico de la República Dominicana. Unidad de Recursos Naturales de la Unión Panamericana.
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- UNEP-WCMC 1997. United Nations List of Protected Areas.
- Wege, D.C., and A.J. Long. 1995. Key areas for threatened birds in the Neotropics. Birdlife international, Smithsonian, Washington, DC.
- WWF-US 2000. Ecoregions of the Caribbean (Map).
- Zonas de Vida n.d.
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