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BIOGEOGRAPHIC REGIONS | AMPHIBIAN DISTRIBUTIONS | REPTILE DISTRIBUTIONS Cuba | Jamaica | Hispaniola | Puerto
Rican Bank | Lesser Antilles |
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Biogeographic regions of Hispaniola (Hedges, 1999)
Lying between Cuba and Puerto Rico,
Hispaniola has an area of 76,470 km2; it is 650 km long by 255 km
wide with a maximum elevation of 3175 m (see figure below). The western one
third of the island is occupied by Haiti and the remainder by the Dominican
Republic. Numerous mountain ranges and valleys dissect this island, which is
divided into two faunistically-defined paleoislands ("North Island"
and "South Island"), separated by a below sea-level trough, the Cul
de Sac and Valle de Neiba. Natural forests are essentially absent from Haiti,
and this has caused widespread silting and destruction of the already
overfished coral reefs. Most remaining forests in the Dominican Republic are
confined to the Cordillera Central, but some relatively small tracts remain in
other upland areas.
Figure. Biogeographic regions of Hispaniola.
Abbreviations: ART Plaine de l'Artibonite, BAR Península de Barahona, CEN
Cordillera Central, CIB Plaine du Nord-Valle de Cibao, CVN Plaine du Cul de
Sac-Valle de Neiba, GON Île Gonâve, HAI Los Haitises, LCC Llanura Costera del
Caribe, LHO Massif de la Hotte, LSB Massif de la Selle-Sierra de Baoruco, MDN
Massif du Nord, MNE Chaîne des Matheux-Sierra de Neiba, NOI Massif des
Montagnes Noires, ORI Cordillera Oriental, PLA Plateau Central, PNO Presqu'île
du Nord Ouest, SAM Península de Samana, SEP Cordillera Septentrional, SMG
Sierra de Martín García, TIB Presqu'île de la Tiburon, TOR Île de la Tortue,
VSJ Valle de San Juan.
Navassa Island.-This is a small island with a steep, rock shoreline
located about 60 km west of the Tiburon peninsula of Haiti.
Massif de la Hotte.-The region defined here forms the core (Montagnes de
la Hotte) of the more inclusive Massif de la Hotte, and includes the highest elevations
(up to 2347 m). Lower elevations largely are barren, and remnants of montane
rainforest and wet limestone forest exist on the slopes and foothills; some
pine forest and cloud forest still may be present on the highest peaks.
Presqu'île de la Tiburon.-The Tiburon peninsula includes some limestone hills
(up to 1340 m), representing the eastern extension of the Massif de la Hotte;
at one time they may have been covered with wet limestone forest.
Massif de la Selle-Sierra de Baoruco.-Two names have applied to this single mountain range
that straddles the international border and is formed largely by an uplifted
limestone platform that has been tilted up toward the north. This has resulted
in a gradual southern incline and a steeper and more rugged northern slope;
both have dry scrub forest at lower elevations. The mostly pine-clad ridge,
rising up to 2690 m elevation, has occasional patches of cloud forest,
especially in the extreme eastern end.
Península de Barahona.-The dry southern península of Hispaniola is a
terraced limestone platform supporting dry scrub forest; the maximum elevation
is 331 m.
Plaine du Cul de Sac-Valle de Neiba.-Separating the two paleoislands of Hispaniola along a
major fault, this long, mostly barren valley (below 100 m elevation) with
occasional patches of dry scrub forest lies below sea level in many places and
has several large hypersaline lakes (e.g., Lago Enriquillo, -42 m).
Île Gonâve.-This is the largest satellite island of Hispaniola
and has an upland area (Montagnes de la Gonâve, rising to 702 m); the island is
densely populated and largely devoid of natural vegetation.
Chaîne des Matheux-Sierra de Neiba.-These ranges, and the Haitian Montagnes Trou D'eau,
are oriented in a northwest-southeast direction and attain moderate to high
elevations (1575 m and 2279 m, respectively). The Haitian ranges have been
largely deforested, but some cloud forest and wet limestone forest are present
in the Sierra de Neiba.
Sierra de Martín García.-Surrounded by xeric lowlands in a region of
relatively low rainfall, this isolated range with a maximum elevation of 1368 m
supports some pine and hardwood forest at upper elevations.
Valle de San Juan.-This is a relatively dry valley (below 400 m
elevation) is the rainshadow of the Cordillera Central and presently an
agricultural region with little remaining natural vegetation.
Plateau Central.-At an elevation of about 300-400 m, this plateau is
an extension of the Valle de San Juan and separates the Massif du Nord from the
Montagnes Noires; there is little or no remaining natural vegetation.
Massif des Montagnes Noires.-These are mostly limestone ridges rising to 1793 m
elevation, now deforested.
Plaine de l'Artibonite.-This floodplain of the large Rivière Artibonite, with
elevations below 100 m, supports some agriculture but no natural vegetation.
Presqu'île du Nord Ouest.-The dry northwest peninsula of Haiti resembles a
barren lunar landscape when viewed from an airplane, but some small patches of
secondary forest remain on steep slopes of the interior ranges; the maximum
elevation is 840 m.
Île de la Tortue.-Once thickly forested with large hardwood trees but
now essentially barren, this large satellite island is mostly limestone; the
maximum elevation is 378 m.
Massif du Nord.-This is the major mountain range of northern Haiti
and represents the northwest extension of the Cordillera Central; the maximum
elevation is 1210 m.
Cordillera Central.-With many peaks above 2000 m, including the highest
point in the West Indies (Pico Duarte, 3087 m), this is the major central
mountain range of Hispaniola. Much of it has been deforested, but the core of
this range and the highest elevations typically support pine (Pinus
occidentalis) on a limestone substrate. Some cloud forest and montane rainforest
exist in patches throughout the range, primarily in the northwest sector.
Plaine du Nord-Valle de Cibao.-This is a mesic, fertile agricultural valley with
elevations below 300 m and with essentially no remaining natural vegetation.
Cordillera Septentrional.-The northern mountain range of the Dominican Republic
is a nearly linear northwest-southeast oriented ridge rising to 1249 m
elevation and with scattered patches of montane rainforest.
Península de Samana.-This rugged, wet, limestone peninsula with several
mountains has only secondary forest remaining; the maximum elevation is 606 m.
Los Haitises.-Wedged between the Cordillera Central and the
Cordillera Oriental, this highly dissected karst area is similar to the Cockpit
Country of Jamaica but lower in elevation. Typical elevations are 150-250 m and
wet limestone forest still exists, primarily on the tops of some mogotes; the
maximum elevation is 467 m.
Cordillera Oriental.-This eastern mountain chain of Hispaniola, attaining
a maximum elevation of 736 m, is continuous with Los Haitises but has little
remaining natural forest.
Llanura Costera del Caribe.-In many places along the coast, this Caribbean
coastal plain is characterized by low (0-20 m) limestone terraces with a
substrate of dogtooth limestone. The depauperate flora of the terraces is
characterized by Bucida buceras, whereas agriculture (primarily sugar
cane) predominates in the more fertile inland areas; the maximum elevation is
200 m.
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Hedges, S. B. 1999. Distribution patterns of
amphibians in the West Indies. Pp. 211-254 In, Duellman, W. E. (Ed.) Patterns
of distribution of amphibians: A global perspective. The Johns Hopkins
University Press, Baltimore.