The Nimba Range forms part of the southern extent of the

Guinea Highlands The Guinea Highlands is a densely forested mountainous plateau extending from central Guinea through northern Sierra Leone and Liberia to western Ivory Coast. The highlands include a number of mountains, ranges and plateaus, including the Fouta ...

. The highest peak is Mount Richard-Molard on the

border Borders are usually defined as geographical boundaries, imposed either by features such as oceans and terrain, or by political entities such as governments, sovereign states, federated states, and other subnational entities. Political borders c ...

Côte d'Ivoire Ivory Coast, also known as Côte d'Ivoire, officially the Republic of Côte d'Ivoire, is a country on the southern coast of West Africa. Its capital is Yamoussoukro, in the centre of the country, while its largest city and economic centre is ...

and

Guinea Guinea ( ),, fuf, 𞤘𞤭𞤲𞤫, italic=no, Gine, wo, Gine, nqo, ߖߌ߬ߣߍ߫, bm, Gine officially the Republic of Guinea (french: République de Guinée), is a coastal country in West Africa. It borders the Atlantic Ocean to the we ...

, at 1,752 m (5,750 ft). "Mount Nimba" may refer either to Mount Richard-Molard or to the entire range. Other peaks include Grand Rochers at 1694 m (5558 ft), Mont Sempéré at 1682 m (5518 ft), Mont Piérré Richaud at 1670 m (5479 ft), Mont Tô at 1675 m (5495 ft), and Mont LeClerc 1577 m (5174 ft), all of them are located in Guinea.

Mount Nimba Strict Nature Reserve Mount Nimba Strict Nature Reserve is a protected area and UNESCO World Heritage Site located in both Guinea and Côte d'Ivoire, extending over a total of area of 17,540 hectares, with 12,540 hectares in Guinea, and 5,000 hectares in Côte d'Ivoire ...

of Guinea and Côte d'Ivoire covers significant portions of the Nimba Range.

Geology

The Nimba Range is a narrow ridge extending approximately 40 km long, with an orientation of northeast-southwest. It is composed mostly of

Precambrian The Precambrian (or Pre-Cambrian, sometimes abbreviated pꞒ, or Cryptozoic) is the earliest part of Earth's history, set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian, the first period of the ...

rock, including

granite Granite () is a coarse-grained (phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies undergro ...

and

quartzite Quartzite is a hard, non- foliated metamorphic rock which was originally pure quartz sandstone.Essentials of Geology, 3rd Edition, Stephen Marshak, p 182 Sandstone is converted into quartzite through heating and pressure usually related to tect ...

which contain deposits of

iron ore Iron ores are rocks and minerals from which metallic iron can be economically extracted. The ores are usually rich in iron oxides and vary in color from dark grey, bright yellow, or deep purple to rusty red. The iron is usually found in the fo ...

. Mining of top-quality iron-ore poses the major threat to the unique geomorphology and wildlife. There are about fifty springs, including the origins of the Cavally,

Cestos Cestos is a settlement in Rivercess County in central Liberia. Located along the Cestos River, it lay at the heart of a heavily contested region during the First Liberian Civil War: the National Patriotic Front of Liberia derived vast amounts of r ...

, and

Sassandra River The Sassandra River is a river of western Côte d'Ivoire in West Africa. It is formed by the confluence of the Tienba River, which originates in the highlands of northwestern Côte d'Ivoire, and the Gouan River (also known as the Bafing Sud Rive ...

Climate

Rainfall varies greatly with elevation and season. About 3,000 mm of rain falls at the highest altitudes, and between 700-1,200 mm at the lower elevations. In fact, some parts of the mountain receive less precipitation, due to rain-shadow effect of the high ridge. Most of the rainfall occurs between May and October.

Ecology

The Nimba Range harbours an especially rich flora and fauna, and it is the home of more than 2000

vascular plant Vascular plants (), also called tracheophytes () or collectively Tracheophyta (), form a large group of land plants ( accepted known species) that have lignified tissues (the xylem) for conducting water and minerals throughout the plant. They al ...

species, 317

vertebrate Vertebrates () comprise all animal taxa within the subphylum Vertebrata () ( chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, ...

species, 107 of which are

mammal Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...

s, and to more than 2,500

invertebrate Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...

species. Notably

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

vertebrates are Nimba viviparous toad (''Nimbaphrynoides occidentalis''),

Lamotte's roundleaf bat Lamotte's roundleaf bat (''Hipposideros lamottei'') is a species of bat found only at Mount Nimba on the border of Côte d'Ivoire, Guinea and Liberia. It is critically endangered. Taxonomy It was described as a new species in 1984 by French zoo ...

(''Hipposideros lamottei''), ''

Myotis nimbaensis The Nimba myotis (''Myotis nimbaensis''), also known as the orange-furred bat or Nimba Mountain bat, is a species of bat in the family Vespertilionidae. The species is endemic to the Nimba Mountains in Guinea, West Africa. It was discovered in 20 ...

'', and

Nimba otter shrew The Nimba otter shrew (''Micropotamogale lamottei'') is a dwarf otter shrew and belongs to the mammal family Potamogalidae. Otter shrews are shrew-like afrotherian mammals found in sub-Saharan Africa. They are most closely related to the tenrecs ...

(''Micropotamogale lamottei''). Other rare and endangered animals are West African lion (''Panthera leo senegalensis''),

pygmy hippopotamus The pygmy hippopotamus or pygmy hippo (''Choeropsis liberiensis'') is a small hippopotamid which is native to the forests and swamps of West Africa, primarily in Liberia, with small populations in Sierra Leone, Guinea, and Ivory Coast. It has bee ...

(''Choeropsis liberiensis''), zebra duiker (''Cephalophus zebra''), and

western chimpanzee The western chimpanzee, or West African chimpanzee, (''Pan troglodytes verus'') is a Critically Endangered subspecies of the common chimpanzee. It inhabits western Africa, specifically Côte d'Ivoire, Guinea, Liberia, Mali, Senegal, Ghana, Guinea ...

(''Pan troglodytes verus'') that uses stones as tools. Terrestrial ecoregions include

Western Guinean lowland forest The Western Guinean lowland forests ecoregion (WWF #AT0130) is a tropical moist broadleaf forest ecoregion of West Africa. It is centered on Liberia, with portions in surrounding countries. It is the westernmost tropical rainforest in Africa, an ...

, Guinean montane forest,

Guinean forest-savanna mosaic Guinea ( ),, fuf, 𞤘𞤭𞤲𞤫, italic=no, Gine, wo, Gine, nqo, ߖߌ߬ߣߍ߫, bm, Gine officially the Republic of Guinea (french: République de Guinée), is a coastal country in West Africa. It borders the Atlantic Ocean to the we ...

, and

West Sudanian savanna The West Sudanian savanna is a tropical savanna ecoregion that extends across West Africa. Geography The ecoregion stretches east and west across West Africa, from the Atlantic coast of Senegal to the Mandara Mountains on Nigeria's eastern borde ...

. The Nimba Range is a part of a distinct freshwater ecoregion with a high portion of endemic aquatic species.

Terrestrial

The plant communities vary with altitude and cardinal orientation. The Guinean montane forests ecoregion covers the portion of the range above 600 meters elevation. Major plant communities in the ecoregion include montane grasslands and savannas, cloud forests, and lower montane forests. High-altitude grasslands and montane savannas cover the highest peaks, dominated by the grass ''

Loudetia kagerensis ''Loudetia'' is a genus of African, Arabian, and South American plants in the grass family.Asplenium schnellii ''Asplenium'' is a genus of about 700 species of ferns, often treated as the only genus in the family Aspleniaceae, though other authors consider ''Hymenasplenium'' separate, based on molecular phylogenetic analysis of DNA sequences, a different ...

'', and two endemic flowering plants, ''

Osbeckia porteresii ''Osbeckia'' is a genus of plants in the family Melastomataceae. It was named by Carl Linnaeus for the Swedish explorer and naturalist Pehr Osbeck (1723–1805). Distribution Osbeckias are native to Eastern Asia — China, Japan, Malaysia, Ind ...

'' and '' Blaeria nimbana''. Shrubs, including ''

Protea occidentalis ''Protea'' () is a genus of South African flowering plants, also called sugarbushes (Afrikaans: ''suikerbos''). Etymology The genus ''Protea'' was named in 1735 by Carl Linnaeus, possibly after the Greek god Proteus, who could change his form a ...

'', inhabit the slopes."Mount Nimba Strict Nature Reserve, Guinea and Côte d'Ivoire". Encyclopedia of Earth. Accessed November 10, 2012

/ref> The endemic frog species '' Nimbaphrynoides occidentalis,'' which inhabits the montane grasslands of the range, is totally

viviparous Among animals, viviparity is development of the embryo inside the body of the parent. This is opposed to oviparity which is a reproductive mode in which females lay developing eggs that complete their development and hatch externally from the m ...

. The Guinea Screeching Frog (''

Arthroleptis crusculum ''Arthroleptis crusculum'' is a species of frog in the family Arthroleptidae. It is found in southern Guinea, Liberia, Sierra Leone, and Côte d'Ivoire, at elevations of above sea level. Its natural habitats are high-altitude grassland, galler ...

'') is a threatened species found on Mt. Nimba and other peaks in the Guinea Highlands. It is found in high-altitude grassland and in gallery forests during the dry season. ''

Ptychadena submascareniensis ''Ptychadena submascareniensis'' (common name: Guinea grassland frog) is a species of frog in the family Ptychadenidae. This West African frog is found on the Nimba Range of Ivory Coast, Guinea, and Liberia, and on the Loma Mountains of Sierra Le ...

'' is another frog species that has been found only on Mount Nimba and in the

Loma Mountains The Loma Mountains are the highest mountain range in Sierra Leone Sierra Leone,)]. officially the Republic of Sierra Leone, is a country on the southwest coast of West Africa. It is bordered by Liberia to the southeast and Guinea surround ...

Sierra Leone Sierra Leone,)]. officially the Republic of Sierra Leone, is a country on the southwest coast of West Africa. It is bordered by Liberia to the southeast and Guinea surrounds the northern half of the nation. Covering a total area of , Sierra ...

. Below the highest peaks, montane grasslands interspersed by gallery forests, between 1,200-1,400 meters. Above 900 meters elevation, near-daily mist and clouds support

cloud forest A cloud forest, also called a water forest, primas forest, or tropical montane cloud forest (TMCF), is a generally tropical or subtropical, evergreen, montane, moist forest characterized by a persistent, frequent or seasonal low-level cloud c ...

s, dominated by the Guinea Plum tree (''

Parinari excelsa ''Parinari excelsa'', the Guinea plum, is a species of large, evergreen tree in the family Chrysobalanaceae. It has a very wide distribution in tropical Africa and South America. This species grows to tall while the trunk is up to in diameter. ...

''), trees of the Myrtle family (

Myrtaceae Myrtaceae, the myrtle family, is a family of dicotyledonous plants placed within the order Myrtales. Myrtle, pōhutukawa, bay rum tree, clove, guava, acca (feijoa), allspice, and eucalyptus are some notable members of this group. All speci ...

), including ''

Syzygium guineense ''Syzygium guineense'' ( bm, Kokisa) is a leafy forest tree of the family Myrtaceae, found in many parts of Africa both wild and domesticated. Both its fruits and leaves are edible; the pulp and the fruit skin are sucked and the seed discarded. I ...

'', and species of ''

Ochna ''Ochna''Linnaeus C (1753) ''Sp. Pl.'' 1: 513. is a genus comprising 86 species of evergreen trees, shrubs and shrublets belonging to the flowering plant family ''Ochnaceae''. These species are native to tropical woodlands of Africa, the Mascare ...

'' and ''

Gaertnera ''Gaertnera'' is a genus of flowering plants in the family Rubiaceae. There are at least 85 species distributed across the Old World tropics from Africa to Asia.

''. The moist climate supports many

epiphyte An epiphyte is an organism that grows on the surface of a plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. The plants on which epiphytes grow are called phoroph ...

s, including an endemic

orchid Orchids are plants that belong to the family Orchidaceae (), a diverse and widespread group of flowering plants with blooms that are often colourful and fragrant. Along with the Asteraceae, they are one of the two largest families of flowering ...

, '' Rhipidoglossum paucifolium''. Lower montane forests of ''

Lophira procera ''Lophira'' is a genus of plants in the family Ochnaceae. Almost every part of ''Lophira'' (bark, root bark, leaves, and leafy shoots) is used for various medicinal purposes. Species include: * ''Lophira alata'' Banks ex C.F.Gaertn. * ''Lophi ...

'', '' Tarrietia utilis'', ''

Mapania ''Mapania'' is a genus of plants in the family Cyperaceae. It contains around 60-70 species, distributed in tropical regions of Africa, India, southern China, Southeast Asia, New Guinea, Australia, Central America, northern South America ...

'' spp., ''

Chlorophora regia ''Milicia regia'' is a species of tropical tree in the family Moraceae. It grows in a belt on the west coast of Africa that extends from the Gambia to Ghana. It is threatened by habitat loss and logging. Description ''Milicia regia'' has a wide ...

'', '' Morus mesozygia'', and ''

Terminalia ivorensis ''Terminalia ivorensis'' is a species of tree in the family Combretaceae, and is known by the common names of Ivory Coast almond, idigbo, black afara, framire and emeri. Description ''Terminalia ivorensis'' is found in Cameroon, Ivory Coast, Gh ...

'' occur between 600 and 900 meters elevation. Below 600 meters, the montane forests transition to the Western Guinean lowland forests ecoregion. The mountain is surrounded by Guinean forest-savanna mosaic, and

Freshwater

Swift-running streams descend steep slopes of the range, and often experience torrential floods during the rainy season. Rheophytes, plants that can live in running water, dominate the aquatic vegetation. The endemic aquatic animals in the Nimba Range includes frogs, fish, the Nimba Stream Crab ''(Liberonautes nimba)'', and the endangered

''(Micropotamogale lamottei)''. The

African clawless otter The African clawless otter (''Aonyx capensis''), also known as the Cape clawless otter or groot otter, is the second-largest freshwater otter species. It inhabits permanent water bodies in savannah and lowland forest areas through most of sub- ...

''(Aonyx capensis)'' also inhabits the mountain streams. Species richness is high among aquatic invertebrates, including 81 species of dragonflies. The WWF designates the Nimba Range a distinct freshwater ecoregion because of its moderate species richness and high proportion of

aquatic species, particularly among fish and amphibians. The Nimba Range's high elevation, its rapids and waterfalls that isolate habitat areas, and the stability of the aquatic environment, have promoted

speciation Speciation is the evolutionary process by which populations evolve to become distinct species. The biologist Orator F. Cook coined the term in 1906 for cladogenesis, the splitting of lineages, as opposed to anagenesis, phyletic evolution within ...

. The

Guinean Highlands The Guinea Highlands is a densely forested mountainous plateau extending from central Guinea through northern Sierra Leone and Liberia to western Ivory Coast. The highlands include a number of mountains, ranges and plateaus, including the Fouta Dj ...

, of which the Nimba Range are part, separate the coastal rivers and streams of

Upper Guinea Upper Guinea is a geographical term used in several contexts: # Upper Guinea (french: Haute-Guinée) is one of the four geographic regions of the Republic of Guinea, being east of Futa Jalon, north of Forest Guinea, and bordering Mali. The populat ...

from the upper

Niger River The Niger River ( ; ) is the main river of West Africa, extending about . Its drainage basin is in area. Its source is in the Guinea Highlands in south-eastern Guinea near the Sierra Leone border. It runs in a crescent shape through ...

basin. The highlands form a barrier to movement of aquatic species between these freshwater regions. The fish fauna of the Nimba Range shares affinities with that of

."Mount Nimba". Freshwater Ecoregions of the World, accessed November 10, 201

/ref>

Mount Nimba Strict Nature Reserve

In 1943, the colonial government established a Strict Nature Reserve in the Côte d'Ivoire section of the range. It was extended into Guinea the following year. The area remained protected after Guinea and Côte d'Ivoire became independent.

UNESCO The United Nations Educational, Scientific and Cultural Organization is a specialized agency of the United Nations (UN) aimed at promoting world peace and security through international cooperation in education, arts, sciences and culture. It ...

declared Mount Nimba a biosphere reserve in 1980, and a

World Heritage Site A World Heritage Site is a landmark or area with legal protection by an international convention administered by the United Nations Educational, Scientific and Cultural Organization (UNESCO). World Heritage Sites are designated by UNESCO for h ...

shortly thereafter.

References

External links

Mount Nimba (Freshwater Ecoregions of the World)

Guinean Montane Forests (Encyclopedia of Earth)

Western Guinean lowland forests (Encyclopedia of Earth)

Guinean forest-savanna mosaic (Encyclopedia of Earth)

Mount Nimba Strict Nature Reserve, Guinea and Côte d'Ivoire (Encyclopedia of Earth)

Mount Nimba Strict Nature Reserve, Guinea and Côte d'Ivoire (UNESCO)

Mount Nimba Strict Nature Reserve, Guinea and Côte d'Ivoire (UNESCO MAB Biosphere Reserves Directory)

{{Coord, 7, 34, N, 8, 28, W, display=title, region:LR_type:mountain_source:GNS-enwiki Afromontane Ecoregions of Guinea Ecoregions of Ivory Coast Ecoregions of Liberia Freshwater ecoregions of Africa Guinean montane forests Mountain ranges of Guinea Mountain ranges of Ivory Coast Mountain ranges of Liberia Montagnes District