The Guianan mangroves (NT1411) is a coastal

ecoregion An ecoregion (ecological region) or ecozone (ecological zone) is an ecologically and geographically defined area that is smaller than a bioregion, which in turn is smaller than a biogeographic realm. Ecoregions cover relatively large areas of l ...

of southeastern

Venezuela Venezuela (; ), officially the Bolivarian Republic of Venezuela ( es, link=no, República Bolivariana de Venezuela), is a country on the northern coast of South America, consisting of a continental landmass and many islands and islets in th ...

Guyana Guyana ( or ), officially the Cooperative Republic of Guyana, is a country on the northern mainland of South America. Guyana is an indigenous word which means "Land of Many Waters". The capital city is Georgetown. Guyana is bordered by the ...

Suriname Suriname (; srn, Sranankondre or ), officially the Republic of Suriname ( nl, Republiek Suriname , srn, Ripolik fu Sranan), is a country on the northeastern Atlantic coast of South America. It is bordered by the Atlantic Ocean to the north ...

French Guiana French Guiana ( or ; french: link=no, Guyane ; gcr, label=French Guianese Creole, Lagwiyann ) is an overseas departments and regions of France, overseas department/region and single territorial collectivity of France on the northern Atlantic ...

and

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

. The

mangrove A mangrove is a shrub or tree that grows in coastal saline water, saline or brackish water. The term is also used for tropical coastal vegetation consisting of such species. Mangroves are taxonomically diverse, as a result of convergent evoluti ...

s provide an important habitat for migrating birds that winter in the area. Large areas are intact, although they are threatened by destruction of the trees for timber and to make way for agriculture, and from upstream agricultural and industrial pollution.

Location

The Guianan mangroves ecoregion extends along the Atlantic coasts of northeastern Venezuela, Guyana, Suriname, French Guiana, and Cabo Orange in Brazil. It covers an area of about between the deltas of the

Orinoco The Orinoco () is one of the longest rivers in South America at . Its drainage basin, sometimes known as the Orinoquia, covers , with 76.3 percent of it in Venezuela and the remainder in Colombia. It is the fourth largest river in the wor ...

and

Oyapock The Oyapock or Oiapoque (; ; ) is a long river in South America that forms most of the border between the French overseas department of French Guiana and the Brazilian state of Amapá. Course The Oyapock runs through the Guianan moist fores ...

rivers. It includes the

Gulf of Paria The Gulf of Paria ( ; es, Golfo de Paria) is a shallow (180 m at its deepest) semi-enclosed inland sea located between the island of Trinidad (Republic of Trinidad and Tobago) and the east coast of Venezuela. It separates the two countries ...

and the delta of the San Juan River. The largest part is in Venezuela in and around the Orinoco delta. The mangroves lie between the sea and areas of

Orinoco Delta swamp forests The Orinoco Delta swamp forests (NT0147) is an ecoregion of eastern Venezuela and northern Guyana covering the large and shifting Orinoco Delta. The vegetation is mostly permanently flooded rainforest. The ecoregion is relatively intact apart fro ...

Guianan moist forests The Guianan moist forests (NT0125) is an ecoregion in the east of Venezuela, north of Brazil and the Guyanas (Guyana, Suriname and French Guiana). It is in the Amazon biome. The climate is hot and humid, with two rainy seasons each year. As of 1996 ...

and Guianan freshwater swamp forests. The Guianan mangroves ecoregion is part of the Guianan-Amazon Mangroves global ecoregion, which also contains the Amapa mangroves, Pará mangroves and

Maranhão mangroves The Maranhão mangroves (in Portuguese: ''Reentrâncias Maranhenses'') is a mangrove ecoregion of northern Brazil. It supports half of the shorebird population of the country. The combination of flat land, heavy rainfall and high tides causes the ...

ecoregions.

Physical

Elevations in the flat, narrow strip of coastal land covered by the mangroves range from sea level to about above sea level. Sand and shell ridges and elevated mud flats are formed by accumulated sediments, carried steadily westward from the mouth of the Amazon by strong ocean currents. The mud flats evolve into clay flats occupied by some species of mangrove. The coastlines suffer periodically from extensive erosion after large number of mangroves die at the same time. Other habitats are brackish or salt lagoons, brackish herbaceous swamps, swamp woods and swamp forests. The swamps are a source of fresh water to the mangroves. The alluvial plains in the northwest have different characteristics. The San Juan delta has swamps with marine-fluvial sediment deposits, the Gulf of Paria has marine sediments and the Orinoco delta has mainly fluvial sediments. The tides are no more than in the Orinoco delta. The Oronoco river has an average flow of per second, and deposits 200,000 tons of sediment each year, resulting in a very unstable landscape.

Climate

There are considerable differences in climate along the length of the ecoregion. Annual rainfall varies from in Venezuela to the east of the Gulf of Paria to in parts of Suriname. Some areas have a four-month dry season while others have none. In the Orinoco Delta the mean monthly temperature ranges from .

Flora

The composition of the mangrove forests depend on the soil and the salinity of the water. Mixed stands of

Rhizophora ''Rhizophora'' is a genus of tropical mangrove trees, sometimes collectively called true mangroves. The most notable species is the red mangrove (''Rhizophora mangle'') but some other species and a few natural hybrids are known. ''Rhizophora'' sp ...

and

Avicennia ''Avicennia'' is a genus of flowering plants currently placed in the bear's breeches family, Acanthaceae. It contains mangrove trees, which occur in the intertidal zones of estuarine areas and are characterized by its "pencil roots", which are a ...

species are found in areas of higher salinity, particularly in the extreme northwest. Rhizophora and

Laguncularia ''Laguncularia'' is a genus of plants in the family Combretaceae The Combretaceae, often called the white mangrove family, are a family of flowering plants in the order Myrtales. The family includes about 530 species of trees, shrubs, and lia ...

species grow in channels with more fresh water, and Rhizophora, Avicennia and Laguncularia grow where the soil contains more organic matter. The higher zones hold forests dominated by Avicennia species while herbaceous vegetation grows in the more saline swamps. There are diverse habitats in the Orinoco delta. The most saline parts have formations of ''

Rhizophora mangle ''Rhizophora mangle'', the red mangrove, is distributed in Estuary, estuarine ecosystems throughout the tropics. Its Vivipary, viviparous "seeds", in actuality called propagules, become fully mature plants before dropping off the parent tree. Th ...

'', ''

Rhizophora harrisonii ''Rhizophora harrisonni'' is a species of plant in the family Rhizophoraceae. It can be found in Brazil, Cameroon, Colombia, Costa Rica, Ecuador, Guyana, French Guiana, Honduras, Nicaragua, Panama, Suriname, Trinidad, Tobago, and Venezuela. De ...

'' and ''

Rhizophora racemosa ''Rhizophora racemosa'' is a species of mangrove tree in the family Rhizophoraceae. It has a patchy distribution on the Pacific coast of Central and South America, occurs in places on the Atlantic coast of that continent, and has a more widesprea ...

''. In less saline areas further inland Rhizophora species and the palm ''

Mauritia flexuosa ''Mauritia flexuosa'', known as the moriche palm, ''ité'' palm, ''ita'', ''buriti'', ''muriti'', ''miriti'' (Brazil), ''canangucho'' (Colombia), ''acho'' (Ecuador), or ''aguaje'' (Peru), is a Arecaceae, palm tree. It grows in and near swamps and ...

'' grow together in peat bogs. In other parts of the delta the Rhizophora species mingle with swamp forest species such as '' Pterocarpus officinalis'', ''

Symphonia globulifera ''Symphonia globulifera'', commonly known as boarwood, is a timber tree abundant in Central America, the Caribbean, South America and Africa. This plant is also used as a medicinal plant and ornamental plant. Common names Common trade names of t ...

'',

açaí palm The açaí palm (, , from Nheengatu ''asai''), ''Euterpe oleracea,'' is a species of palm tree (Arecaceae) cultivated for its fruit (açaí berries, or simply açaí), hearts of palm (a vegetable), leaves, and trunk wood. Global demand for the f ...

(''Euterpe oleracea'') and

Roystonea ''Roystonea'' is a genus of eleven species of monoecious palms, native to the Caribbean Islands, and the adjacent coasts of the United States (Florida), Central America and northern South America. Commonly known as the royal palms, the genus wa ...

species. There are wide belts of

in the inner estuary, with

on higher ground, sometimes mixed with ''Pterocarpus officinalis'', ''Symphonia globulifera'' and

Vitex ''Vitex'' is a genus of flowering plants in the sage family Lamiaceae.List of Genera in Lamiaceae. At: Peter F. Stevens. 2001 onwards. Angiosperm Phylogeny Website At: Missouri Botanical Garden Website. (see ''External links'' below). It has ...

species.

Along the coast from eastern Venezuela to the Guyanas the mangroves form belts a few meters wide associated with deciduous forests, muddy meadows and muddy forests in flooded areas. Dominant species include '' Costus arabicus'', ''

Cyperus giganteus ''Cyperus giganteus'' (also known as piripiri) is a perennial herbaceous plant. It belongs to the genus ''Cyperus''. Its native range extends from Jalisco in west-central Mexico as far south as Uruguay, and also grows on some islands in the Car ...

'', ''

Eichhornia crassipes ''Pontederia crassipes'' (formerly ''Eichhornia crassipes''), commonly known as common water hyacinth is an aquatic plant native to South America, naturalized throughout the world, and often invasive species, invasive outside its native range ...

'', '' Heliconia psittacorum'', ''

Roystonea regia ''Roystonea regia'', commonly known as the Cuban royal palm or Florida royal palm, is a species of palm that is native to Mexico, parts of Central America and the Caribbean, and southern Florida. A large and attractive palm, it has been planted ...

'' and ''

''. Muddy forests on ground that is almost always flooded have a single dense stratum of trees with heights from such as ''Pterocarpus officinalis'', ''Symphonia globulifera'', '' Tabebuia aquatilis'', açaí palm (''Euterpe oleracea''),

Manicaria ''Manicaria'' is a palm genus which is found in Trinidad, Central and South America. It contains two recognized species: #'' Manicaria martiana'' Burret – Colombia, northwestern Brazil #''Manicaria saccifera'' Gaertn. – Central America, Tri ...

species and ''

''. The mangrove belts hold ''

Laguncularia racemosa ''Laguncularia racemosa'', the white mangrove, is a species of flowering plant in the leadwood tree family, Combretaceae. It is native to the coasts of western Africa from Senegal to Cameroon, the Atlantic Coast of the Americas from Bermuda and ...

'' on the seaward side, mixed with

Spartina ''Spartina'' is a taxon of plants in the grass family, frequently found in coastal salt marshes. Its species are commonly known as cordgrass or cord-grass, and are native to the coasts of the Atlantic Ocean in western and southern Europe, nort ...

species of salt marsh grass, in front of stands of ''

Avicennia germinans ''Avicennia germinans'', the black mangrove, is a shrub or small tree growing up to 12 meters (39 feet) in the acanthus family, Acanthaceae. It grows in tropical and subtropical regions of the Americas, on both the Atlantic and Pacific Coasts, ...

''.

Fauna

The ecoregion has diverse fauna. It is the largest area in South America where migrating shorebirds from the

Nearctic realm The Nearctic realm is one of the eight biogeographic realms constituting the Earth's land surface. The Nearctic realm covers most of North America, including Greenland, Central Florida, and the highlands of Mexico. The parts of North America t ...

spend the winter, with up to 5 million birds visiting in one year. Over 118 species of birds have been recorded in Suriname and Venezuela, of which more than 70 are waterbirds. Bird species include

scarlet ibis The scarlet ibis (''Eudocimus ruber'') is a species of ibis in the bird family Threskiornithidae. It inhabits tropical South America and part of the Caribbean. In form, it resembles most of the other twenty-seven extant species of ibis, but its ...

(''Eudocimus ruber''), black skimmer (''Rynchops niger''),

gull-billed tern The gull-billed tern (''Gelochelidon nilotica''), formerly ''Sterna nilotica'', is a tern in the family Laridae. It is widely distributed and breeds in scattered localities in Europe, Asia, northwest Africa, and the Americas. The Australian gull ...

(''Gelochelidon nilotica''),

short-billed dowitcher The short-billed dowitcher (''Limnodromus griseus''), like its congener the long-billed dowitcher, is a medium-sized, stocky, long-billed shorebird in the family Scolopacidae. It is an inhabitant of North America, Central America, the Caribbea ...

(''Limnodromus griseus''),

lesser yellowlegs The lesser yellowlegs (''Tringa flavipes'') is a medium-sized shorebird. It breeds in the boreal forest region of North America. Taxonomy The lesser yellowlegs was formally described in 1789 by the German naturalist Johann Friedrich Gmelin in ...

(''Tringa flavipes''),

greater yellowlegs The greater yellowlegs (''Tringa melanoleuca'') is a large shorebird in the family Scolopacidae. It breeds in central Canada and southern Alaska and winters in southern North America, Central America, the West Indies and South America. Taxonomy ...

(''Tringa melanoleuca''),

black-bellied whistling duck The black-bellied whistling duck (''Dendrocygna autumnalis''), formerly called the black-bellied tree duck, is a whistling duck that breeds from the southernmost United States, Mexico, and tropical Central to south-central South America. In the ...

(''Dendrocygna autumnalis'') and

tricolored heron The tricolored heron (''Egretta tricolor''), formerly known as the Louisiana heron, is a small species of heron native to coastal parts of the Americas; in the Atlantic region, it ranges from the northeastern United States, south along the coast ...

(''Egretta tricolor''). More than 50 species of mammals have been recorded, including

opossum Opossums () are members of the marsupial order Didelphimorphia () endemic to the Americas. The largest order of marsupials in the Western Hemisphere, it comprises 93 species in 18 genera. Opossums originated in South America and entered North ...

bat Bats are mammals of the order Chiroptera.''cheir'', "hand" and πτερόν''pteron'', "wing". With their forelimbs adapted as wings, they are the only mammals capable of true and sustained flight. Bats are more agile in flight than most bi ...

tufted capuchin The tufted capuchin (''Sapajus apella''), also known as brown capuchin, black-capped capuchin, or pin monkey is a New World primate from South America and the Caribbean islands of Trinidad and Margarita. As traditionally defined, it is one of th ...

(''Sapajus apella''),

common squirrel monkey Common squirrel monkey is the traditional common name for several small squirrel monkey species native to the tropical areas of South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern ...

(''Saimiri sciureus''),

Venezuelan red howler The Colombian red howler or Venezuelan red howler (''Alouatta seniculus'') is a South American species of howler monkey, a type of New World monkey, found in the western Amazon Basin in Venezuela, Colombia, Ecuador, Peru and Brazil. The populat ...

(''Alouatta seniculus''),

white-faced saki The white-faced saki (''Pithecia pithecia''), called the Guianan saki and the golden-faced saki, is a species of the New World saki monkey. They can be found in Brazil, French Guiana, Guyana, Suriname and Venezuela. This species lives in the und ...

(''Pithecia pithecia''),

giant anteater The giant anteater (''Myrmecophaga tridactyla'') is an insectivorous mammal native to Central and South America. It is one of four living species of anteaters, of which it is the largest member. The only extant member of the genus ''Myrmecopha ...

(''Myrmecophaga tridactyla''),

jaguar The jaguar (''Panthera onca'') is a large cat species and the only living member of the genus '' Panthera'' native to the Americas. With a body length of up to and a weight of up to , it is the largest cat species in the Americas and the th ...

(''Panthera onca''),

cougar The cougar (''Puma concolor'') is a large Felidae, cat native to the Americas. Its Species distribution, range spans from the Canadian Yukon to the southern Andes in South America and is the most widespread of any large wild terrestrial mamm ...

(''Puma concolor''),

ocelot The ocelot (''Leopardus pardalis'') is a medium-sized spotted wild cat that reaches at the shoulders and weighs between on average. It was first described by Carl Linnaeus in 1758. Two subspecies are recognized. It is native to the southwes ...

(''Leopardus pardalis'') and

capybara The capybaraAlso called capivara (in Brazil), capiguara (in Bolivia), chigüire, chigüiro, or fercho (in Colombia and Venezuela), carpincho (in Argentina, Paraguay and Uruguay) and ronsoco (in Peru). or greater capybara (''Hydrochoerus hydro ...

(''Hydrochoerus hydrochaeris''). The paradoxal frog (''

Pseudis paradoxa ''Pseudis paradoxa'', known as the paradoxical frog or shrinking frog, is a species of hylid frog from South America. Its name refers to the very large—up to long—tadpole (the world's longest), which in turn "shrinks" during metamorphosi ...

'') and the

common Suriname toad The common Surinam toad or star-fingered toad (''Pipa pipa'') is an purely aquatic species of frog in the family ''Pipidae'' with a widespread distribution in South America. The species is known for incubating its eggs in honeycombed chambers in ...

(''Pipa pipa'') have adapted to the saline conditions. Reptiles include

olive ridley sea turtle The olive ridley sea turtle (''Lepidochelys olivacea''), also known commonly as the Pacific ridley sea turtle, is a species of turtle in the family Cheloniidae. The species is the second-smallest and most abundant of all sea turtles found in th ...

(''Lepidochelys olivacea''), which nests on the beaches, green iguana (''Iguana iguana''), spectacled caiman (''Caiman crocodilus'') and

green anaconda The green anaconda (''Eunectes murinus''), also known as the giant Emerald anaconda, common anaconda, common water boa or sucuri, is a boa species found in South America. It is the heaviest and one of the longest known extant snake species. Lik ...

(''Eunectes murinus'').

Status

The

World Wildlife Fund The World Wide Fund for Nature Inc. (WWF) is an international non-governmental organization founded in 1961 that works in the field of wilderness preservation and the reduction of human impact on the environment. It was formerly named the Wo ...

gives the ecoregion the status of "Relatively Stable/Intact". There are many protected areas, and large sections of mangroves are intact. Suriname has at least seven protected areas, most with a degree of connectivity, including the Coppename Monding wetland and the Wia-Wia nature reserve. Venezuela has the Mariusa National Park and the Orinoco Delta Biosphere Reserve. The Guarapiche Forest Reserve in the San Juan delta holds a patch of mangroves, palms and swamp forests. Agriculture such as rice cultivation has caused some fragmentation, but most fragmentation is natural. The main threats come from logging to obtain building material, fuel, tannin and medicinal products. Upstream agriculture releases fertilizers and pesticides, and adds sediments due to erosion. Population growth and tourism are increasing use of the mangroves as a source of food such as shrimp and wildlife, or for grazing domestic animals. Unsuccessful hydraulic engineering has damaged the Orinoco delta environment, and oil prospecting is a concern.

References

Sources

* * * {{DEFAULTSORT:Guianan mangroves Ecoregions of Venezuela Mangrove ecoregions Neotropical ecoregions Amazon biome