Cameroonian Highlands forests

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Cameroonian Highlands forests
Gashaka-Gumti National Park, Taraba, Nigeria.jpg
Ecoregion AT0103.svg
Map of the Cameroonian Highlands forests
Ecology
Realm Afrotropical
Biome tropical and subtropical moist broadleaf forests
Borders
Geography
Area38,000 km2 (15,000 sq mi)
Countries
Coordinates 6°N11°E / 6°N 11°E / 6; 11
Conservation
Conservation status Critical/endangered [1]
Protected6.9% [2]

The Cameroonian Highlands forests, also known as the Cameroon Highlands forests, are a montane tropical moist broadleaf forest ecoregion located on the range of mountains that runs inland from the Gulf of Guinea and forms the border between Cameroon and Nigeria. This is an area of forest and grassland which has become more populous as land is cleared for agriculture. [3] [4]

Contents

Geography

The Cameroonian Highlands forests extend across the Cameroon Highlands, a chain of extinct volcanoes, covering an area of 38,000 square kilometers (15,000 sq mi) in eastern Nigeria and western Cameroon. The highlands extend roughly southwest–northeast. In the southwest the ecoregion includes the Rumpi Hills, Bakossi Mountains, Mount Nlonako, Mount Kupe, and Mount Manengouba. It extends northeast towards the Mambila Plateau, and north to the Bamenda Highlands. It continues northeast along the western flank of the Adamawa Plateau to Tchabal Gangdaba. Northern outliers include the Mambilla Plateau to the northeast, Nigeria's Obudu Plateau to the northwest, the Alantika Mountains and Hosséré Vokré to the north, and in the southeastern Adamawa Plateau east of Ngaoundéré. [1]

The ecoregion lies above 900 meters elevation, and is surrounded at lower elevations by the Cross–Sanaga–Bioko coastal forests at the southern end of the range, and by Guinean forest–savanna mosaic along the central and northern ends of the range. The Cameroon Highlands form the boundary between the Guinean and Northern Congolian forest–savanna mosaic ecoregions. The highest peak within the ecoregion is Mount Oku (3,011 metres (9,879 ft)). Mount Cameroon is highest mountain in the chain, but its high-elevation forests are designated a separate ecoregion. [1]

Climate

Mean maximum temperatures are below 20°C due to the effects of altitude, and are cooler than the surrounding lowlands. Average annual rainfall ranges from around 4,000 mm near the coast to 1,800 mm or less further inland. [1] The highlands are an important source of water for both Nigeria and Cameroon.

Flora

The vegetation varies with elevation. Submontane forests extend from approximately 900 metres (2,953 ft) to 2,000 metres (6,562 ft) meters elevation. Above 2,000 metres (6,562 ft) elevation are distinct montane forests and patches of montane grassland, bamboo forest, and subalpine grasslands and shrublands. The ecoregion is characterized by the presence of Afromontane species, which have an archipelago-like distribution across the highlands of Africa and are distinct from the lowland flora. Typical afromontane tree species are Nuxia congesta, Olea capensis, Podocarpus milanjianus, Prunus africana, Myrsine melanophloeos, and Syzygium staudtii . [1] [5]

Submontane forests from 850 to 1600 meters elevation typically have an open canopy. Common trees include species of Alchornea , along with species characteristic of the adjacent lowland plant communities, like semi-deciduous forests (species of Ficus, Santiria, Symphonia, Allanblackia and Anthocleista ) and savanna (species of Lannea, Bridelia, Lophira , and Fabaceae). Grasses are abundant in the understorey. From 1600 to 2000 meters, trees from the Euphorbiaceae family predominate, including species of Macaranga, Alchornea, and Mallotus . Savanna and semi-deciduous forest species - Ficus, Lophira, Bridelia, Lannea, and Fabaceae – are also present. The Afromontane genus Astropanax is abundant, and Afromontane species including Olea capensis, Syzygium, Maesa , Meliaceae, and Clematis grow in smaller numbers. Grasses remain common in the understory. [5]

Afromontane forests grow above 2000 meters elevation. Lower montane forests generally have a denser canopy than the submontane and upper montane forests, with fewer grasses in the shady understorey. Trees in the lower Afromontane forests include species of Astropanax, Alchornea, Myrica, and Ilex , and the palm Elaeis guineensis . Nuxia congesta , Olea capensis, and Astropanax are predominant from 2270 to 2500 meters elevation. In the upper montane forest from 2500 to 2945 meters elevation Podocarpus milanjianus and Astropanax are predominant, together with Myrsine melanophloeos, Syzygium, Prunus africana, Ixora , and shrubs and herbs like Isoglossa, Pavetta, Rubus , and Impatiens . [5]

The climate is drier further inland, and rainfall more seasonal. In the northern mountains, including the Adamawa Plateau, Hosséré Vokré, and Alantika mountains, submontane forests generally absent, and the Afromontane forests transition directly to savanna. Afromontane forests on the Hosséré Vokré and Alantika mountains are generally limited to stream valleys and ravines, separated by areas of montane savanna or grassland. [6] [7]

The ericaceous belt is a transition between the upper montane forests and high-elevation grasslands, ranging from approximately 2750 up to 2950 meters elevation. Shrubs and stunted trees of genus Ericaceae, including Erica mannii and Erica silvatica , are predominant. [5]

Subalpine grasslands grow above 2800 meters elevation, with many grasses, and herbs in the genera Alchemilla and Anthospermum and the families Caryophyllaceae, Asteraceae, and Lamiaceae. [5]

Fauna

The ecoregion is home to a number of endemic species, along with several more that are also found in the nearby Mount Cameroon and Bioko montane forests ecoregion.

Six species of birds are strictly endemic: the Bamenda apalis (Apalis bamendae), white-throated mountain-babbler (Kupeornis gilberti), banded wattle-eye (Platysteira laticincta), Bannerman's weaver (Ploceus bannermani), Mount Kupe bush-shrike (Telophorus kupeensis) and Bannerman's turaco (Tauraco bannermani), which is a cultural icon for the Kom people who live in the area. Seven species are endemic to the Cameroon Highlands forests and Mount Cameroon: Cameroon greenbul (Arizelocichla montana), Bangwa forest warbler (Bradypterus bangwaensis), grey-headed greenbul (Phyllastrephus poliocephalus), yellow-breasted boubou (Laniarius atroflavus), green-breasted bushshrike (Malaconotus gladiator), mountain robin-chat (Cossyphicula isabellae) and a subspecies of Chubb's cisticola, Cisticola chubbi discolor (sometimes considered a separate species C. discolor). Nine more montane endemic species are shared with Mount Cameroon and Bioko: the western greenbul (Arizelocichla tephrolaema), Cameroon olive greenbul (Phyllastrephus poensis), black-capped woodland warbler (Phylloscopus herberti), green longtail (Urolais epichlorus), white-tailed warbler (Poliolais lopezi), Cameroon sunbird (Cyanomitra oritis), Ursula's sunbird (Cinnyris ursulae), Shelley's oliveback (Nesocharis shelleyi), and Cameroon olive-pigeon (Columba sjostedti). [1] [6]

Eleven small mammal species are endemic to the ecoregion: Eisentraut's striped mouse (Hybomys eisentrauti), the Mount Oku hylomyscus (Hylomyscus grandis), Mount Oku rat (Lamottemys okuensis), Mittendorf's striped grass mouse (Lemniscomys mittendorfi), Dieterlen's brush-furred mouse (Lophuromys dieterleni) and Eisentraut's brush-furred rat (L. eisentrauti), Oku mouse shrew (Myosorex okuensis,) Rumpi mouse shrew (M. rumpii), western vlei rat (Otomys occidentalis), Hartwig's soft-furred mouse (Praomys hartwigi), and Bioko forest shrew ( Sylvisorex isabellae ). [1]

The ecoregion is home to several endangered primates, including the Cross River gorilla (Gorilla gorilla diehli), an endemic subspecies of western gorilla, mainland drill (Mandrillus leucophaeus leucophaeus), Preuss's red colobus (Pilocolobus preussi), chimpanzee ( Pan troglodytes ) and several species of guenon including Preuss's monkey (Cercopithecus preussi). [1]

Forty species of amphibians are endemic to the ecoregion: Petropedetes parkeri , Petropedetes perreti , Phrynobatrachus cricogaster , Phrynobatrachus steindachneri , Phrynobatrachus werneri , Phrynobatrachus species, Phrynodon species, Cardioglossa melanogaster , Cardioglossa oreas , Cardioglossa pulchra , Cardioglossa schioetzi , Cardioglossa trifasciata , Cardioglossa venusta , Astylosternus nganhanus , Astylosternus perreti , Astylosternus montanus , Astylosternus rheophilus , Leptodactylodon axillaris , Leptodactylodon bicolor , Leptodactylodon boulengeri , Leptodactylodon erythrogaster , Leptodactylodon mertensi , Leptodactylodon polyacanthus , Leptodactylodon perreti , Afrixalus lacteus , Hyperolius ademetzi , Hyperolius riggenbachi , Leptopelis nordequatorialis , Xenopus amieti , Xenopus species, Bufo villiersi , Werneria bambutensis , Werneria tandyi , Wolterstorffina mirei . [1]

The following reptiles are also considered more or less endemic: Atractaspis coalescens , Pfeffer's chameleon (Trioceros pfefferi), four-horned chameleon (Trioceros quadricornis), Leptosiaphos ianthinoxantha , Angel's five-toed skink (Lacertaspis lepesmei), [1] and the gecko Ancylodactylus alantika .

Urban areas and settlements

In Cameroon the mountains are quite heavily populated and used for farming and grazing; much of this ecoregion lies in the Northwest and Adamawa Regions. Towns include Bamenda, capital of the Northwest and base for visiting the mountains including Oku, the Kilum-Ijim Forest and Lake Nyos. In Nigeria the ecoregion is located mainly on the Mambila Plateau, an area of agricultural and grazing land in Taraba State.

Conservation and threats

The forest is continually being cleared for firewood, timber and to create farmland, and many of the mountains have lost significant amounts of forest cover. There is very little formal environmental protection.

Protected areas

6.9% of the ecoregion is in protected areas. Protected areas include Gashaka-Gumti National Park, Korup National Park, Bayang-Mbo Wildlife Sanctuary, Santchou Faunal Reserve, Gangoro Forest Reserve, Mai Samari Forest Reserve, Ngel-Nyaki Forest Reserve, River Nwum Forest Reserve, Kakara Forest Reserve, and Nguroje Forest Reserve. [2]

Related Research Articles

<span class="mw-page-title-main">Mount Cameroon</span> Active volcano in Cameroon near the Gulf of Guinea

Mount Cameroon is an active volcano in the South West region of Cameroon next to the city of Buea near the Gulf of Guinea. Mount Cameroon is also known as Cameroon Mountain or Fako or by its indigenous name Mongo ma Ndemi. Mount Cameroon is ranked 22nd by topographic isolation.

<span class="mw-page-title-main">Eastern Highlands</span> Mountain range in Zimbabwe and Mozambique

The Eastern Highlands, also known as the Manica Highlands, is a mountain range on the border of Zimbabwe and Mozambique. The Eastern Highlands extend north and south for about 300 kilometres (190 mi) through Zimbabwe's Manicaland Province and Mozambique's Manica Province.

<span class="mw-page-title-main">Ethiopian Highlands</span> Mountain range in northern Ethiopia

The Ethiopian Highlands is a rugged mass of mountains in Ethiopia in Northeast Africa. It forms the largest continuous area of its elevation in the continent, with little of its surface falling below 1,500 m (4,900 ft), while the summits reach heights of up to 4,550 m (14,930 ft). It is sometimes called the "Roof of Northeastern Africa" due to its height and large area. It is the only country in the region with such a high elevated surface. This elevated surface is bisected diagonally by the Great East African Rift System which extends from Syria to Mozambique across the East African Lakes. Most of the Ethiopian Highlands are part of central and northern Ethiopia, and its northernmost portion reaches into Eritrea.

<span class="mw-page-title-main">Afromontane</span> Subregion of the Afrotropical realm

The Afromontane regions are subregions of the Afrotropical realm, one of the Earth's eight biogeographic realms, covering the plant and animal species found in the mountains of Africa and the southern Arabian Peninsula. The Afromontane regions of Africa are discontinuous, separated from each other by lower-lying areas, and are sometimes referred to as the Afromontane archipelago, as their distribution is analogous to a series of sky islands.

<span class="mw-page-title-main">Northern Congolian forest–savanna mosaic</span> Forest and savanna ecoregion of Central Africa

The Northern Congolian forest–savanna mosaic is a forest and savanna ecoregion of central Africa. It extends east and west across central Africa, covering parts of Cameroon, Central African Republic, Democratic Republic of the Congo, South Sudan, and Uganda. It is part of the belt of transitional forest-savanna mosaic that lie between Africa's moist equatorial Guineo-Congolian forests and the tropical dry forests, savannas, and grasslands to the north and south.

<span class="mw-page-title-main">Wildlife of Cameroon</span>

The wildlife of Cameroon is composed of its flora and fauna. Bordering Nigeria, it is considered one of the wettest parts of Africa and records Africa's second highest concentration of biodiversity. To preserve its wildlife, Cameroon has more than 20 protected reserves comprising national parks, zoos, forest reserves and sanctuaries. The protected areas were first created in the northern region under the colonial administration in 1932; the first two reserves established were Mozogo Gokoro Reserve and the Bénoué Reserve, which was followed by the Waza Reserve on 24 March 1934. The coverage of reserves was initially about 4 percent of the country's area, rising to 12 percent; the administration proposes to cover 30 percent of the land area.

<i>Astylosternus perreti</i> Species of frog

Astylosternus perreti, also known as Perret's night frog is a species of frog in the family Arthroleptidae. It is endemic to western Cameroon and known from Mount Manengouba and from parts of the Bamileke Highlands, at elevations of 1,200–1,400 m (3,900–4,600 ft) above sea level. It is one of the few species of African frogs to have claws, used on demand, when it feels threatened.

Isoglossa nervosa is a species of plant in the family Acanthaceae. It is an herbaceous perennial or subshrub native to southeastern Nigeria, Cameroon, and Bioko island in Equatorial Guinea. Its natural habitat is tropical montane forest from 2,000 to 2,950 meters elevation.

Astropanax barteri is a species of plant in the family Araliaceae.

<span class="mw-page-title-main">Mount Cameroon and Bioko montane forests</span>

The Mount Cameroon and Bioko montane forests is a tropical moist broadleaf forest ecoregion in central Africa. It occupies the upper slopes of coastal Mount Cameroon in Cameroon, and the mountains of nearby Bioko island in Equatorial Guinea.

<span class="mw-page-title-main">South Malawi montane forest–grassland mosaic</span>

The South Malawi montane forest–grassland mosaic is an ecoregion of Malawi.

<span class="mw-page-title-main">Angolan montane forest–grassland mosaic</span>

The Angolan montane forest-grassland mosaic ecoregion is located on the east-facing inland side of the belt of mountains that stands parallel to the coast of Angola, 50–100 km inland.

<span class="mw-page-title-main">Mount Oku</span>

Mount Oku, or Kilum Mountain, is the largest volcano in the Oku Massif, in the Cameroon Volcanic Line, located in the Oku region of the Western High Plateau of Cameroon. It is the second highest mountain in mainland Central Africa. The stratovolcano rises to 3,011 metres (9,879 ft) above sea level, and is cut by a large caldera.

The Atlantika Mountains, also known as the Alantika Mountains, are an extension of the Cameroon line of volcanic mountains, spanning the border between Nigeria and Cameroon. They lie to the southeast of Yola, the capital of Adamawa State in Nigeria, and southwest of the Mandara mountains. In Cameroon, they are part of the North Region. They are north of the Adamawa Plateau and west of the Faro National Park in Cameroon. The massif rises to about 1,300 metres (4,300 ft) above the Faro River, a tributary of the Benue River. The range includes a belt of volcanoes, most of which are inactive. The mountains' landscape includes outcrops of large granite boulders.

<span class="mw-page-title-main">East African montane forests</span>

The East African montane forests is a montane tropical moist forest ecoregion of eastern Africa. The ecoregion comprises several separate areas above 2000 meters in the mountains of South Sudan, Uganda, Kenya, and Tanzania.

<span class="mw-page-title-main">Mandara Plateau mosaic</span> Ecoregion in the Mandara Mountains, Nigeria-Cameroon

The Mandara Plateau mosaic, also known as the Mandara Plateau woodlands, is a tropical grasslands, savannas, and shrublands ecoregion located in the Mandara Mountains of northern Nigeria and Cameroon.

<span class="mw-page-title-main">Ethiopian montane forests</span> Tropical moist broadleaf forest ecoregion in Ethiopia

The Ethiopian montane forests is a tropical moist broadleaf forest ecoregion in eastern Africa. It covers the middle elevations of the Ethiopian Highlands in Ethiopia and extends into neighboring Eritrea, Sudan, Djibouti, and Somaliland. The ecoregion includes distinctive Afromontane forests, woodlands, grasslands, and shrublands. The ecoregion's biodiversity is threatened by deforestation, conversion to agriculture, and overgrazing.

<i>Phrynobatrachus jimzimkusi</i> Species of amphibian

Phrynobatrachus jimzimkusi is a species of frogs in the family Phrynobatrachidae. It is found in submontane and montane regions within the Cameroon volcanic line as well as the adjacent Obudu Plateau in the southeast of Nigeria. It is named after James (Jim) Zimkus by his wife, Breda Zimkus, the first author of the species description. Common name Jim Zimkus' puddle frog has been proposed for this species.

The Njesi Highlands are a range of mountains in northern Mozambique.

Hosséré Vokré is an isolated plateau in the North Region of Cameroon. It covers approximately 930 square kilometres (360 sq mi), and forms a broad u-shaped ridge that opens northwards toward the town of Poli. Its highest point is 2,049 metres (6,722 ft). ‘Hosséré' is a regional term for isolated massifs which rise above the savanna lowlands. The Hosséré Godé massif is close by to the northwest. It is separated from other mountains by lowlands less than 500 meters in elevation, including the Alantika Mountains to the northwest along the Nigeria–Cameroon border, and the Adamawa Plateau to the south.

References

  1. 1 2 3 4 5 6 7 8 9 10 "Cameroonian Highlands forests". Terrestrial Ecoregions. World Wildlife Fund.
  2. 1 2 "Cameroonian Highlands forests". DOPA Explorer. Accessed 7 August 2021.
  3. "Map of Ecoregions 2017". Resolve. Retrieved August 20, 2021.
  4. "Cameroonian Highlands forests". The Encyclopedia of Earth. Retrieved August 20, 2021.
  5. 1 2 3 4 5 Lorelei Verlhac, Kenji Izumi, Anne-Marie Lézine, Kévin Lemonnier, Guillaume Buchet, Gaston Achoundong, Barthélémy Tchiengué (2018). Altitudinal distribution of pollen, plants and biomes in the Cameroon highlands. Review of Palaeobotany and Palynology, Volume 259, 2018, Pages 21-28. ISSN 0034-6667. https://doi.org/10.1016/j.revpalbo.2018.09.011.
  6. 1 2 BirdLife International (2024) Endemic Bird Areas factsheet: Cameroon mountains. Retrieved 25 February 2024.
  7. B. Larison, T. B. Smith, D. Mcniven, R. Fotso, M. Bruford, K. Holbrook,and A. Lamperti, Faunal Surveys of Selected Montane and Lowland Areas of Cameroon, WWF Cameroon, 1996, unpubl. PDF