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 (Tasaico 1967; Dominican Republic 1998; WWF-US 2000).
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 (Hartshorn 1981; Zonas de Vida n.d.). 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) (Tolentino 1998).
The vegetation on the savannahs (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.) (Hartshorn 1981; Zonas de Vida n.d.; DIRENA (in press).
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 (Dinerstein et al. 1995; Olson et al. 1997). These forests have been isolated from the contiguous continents and have thus maintained relict taxons (Olson et al. 1997). In the mountains of Selle-Bahoruco alone there are five endemic genera of plants (Olson et al. 1996). This ecoregion is found in the five most important centers of plant diversity and endemism on the island (Davis et al. 1997). 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 (CPD Cb9) 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 (Grupo Jaragua 1994).
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 (Wege et al. 1995; García, R. 1994; Harcourt et al. 1996).
According to Dinerstein et al. 1995, 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. According to Olson et al. 1996, 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 (based on interpretation of Landsat images from 1988 to 1996), 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% (Grupo Jaragua 1994). The forest situation of Haiti is an even greater concern in that only 1.44% of the total original forest coverage remains (Strauss 2000). Less than 200 km2 of unaltered rainforest remains in Haiti (STD 1979)
In the Dominican Republic, this ecoregion is protected in part in the Armando Bermúdez National Park (766 km2, IUCN category II), the José del Carmen Ramírez National Park (764 km2, IUCN category II), the Valle Nuevo Scientific Reserve (409 km2, IUCN category IV), Ébano Verde Scientific Reserve (23 km2, IUCN category IV), the Sierra de Neiba National Park (407 km2, IUCN category II), the Sierra Bahoruco National Park (1.027 km2, IUCN category II), the Mirador del Paraíso Scenic Route (IUCN category V), the National Park of the East (433 km2 , IUCN category II) and Los Haitises National Park (208 km , IUCN category II) (CEP 1996; UNEP 1997).
In Haiti, this ecoregion is only represented in parts of the Pic Macaya National Park (55 km2, IUCN category II) and the La Visite National Park (20 km2, IUCN category II) (CEP 1996; UNEP 1997; DNP (Dirección Nacional de Parques) 1980).
Types and Severity of Threats
According to Dinerstein et al. 1995, 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 (CONATEF/FAO 1991; CRIES 1980; ).
Justification of Ecoregion Delineation
Justification and linework will be available by January 2002.
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Zonas de Vida n.d. http://jmarcano.webjump.com<
Prepared by: Ugo D'Ambrosio
Reviewed by: Rosemarie Gnam (American Museum of Natural History)