Known by the local people as “messengers of God” for their habitual movements between the treetops and the ground, the king colobus monkey inhabits the Eastern Guinean Forests, but only to the east of the Sassandra River. For many species living in this ecoregion, the Sassandra River—which separates the Western Guinean Forests ecoregion from this one—has influenced their distribution and evolution. The gradual transition of this ecoregion, from moist evergreen forest in the south of Côte d’Ivoire and Ghana to dry semi-evergreen forest further north, provides the perfect habitat for a rich assortment of flora and fauna.
The ecoregion extends from the east banks of the Sassandra River in western Côte d’Ivoire to the edge of Lake Volta in Ghana. There is a small extension east of Lake Volta in the Togo Hills. The Dahomey Gap is a dry lowland area and a major biogeographical barrier on the ecoregion’s eastern edge. Topography generally undulates between 50 and 300 m, with occasional inselbergs rising to over 400 m. Within the Togo Hills, the maximum elevation reaches 1,000 m.
Temperatures in the south range between 22ºC and 34ºC, whereas in the north, temperatures can reach a maximum of 43ºC and fall to 10ºC. There are distinct wet and dry seasons, with a longer dry season than in the Western Guinean Lowland Forests ecoregion. In Benin and Togo, rainfall seldom exceeds 1,500 mm, but further to the west rainfall can average 2,500 mm per year.
The moist evergreen forests in the extreme south of the ecoregion are represented by trees including Entandroophragma utile, Khaya ivorensis, and Triplochiton scleroxylon; the semi-deciduous forests in the northern parts are dominated by Celtis spp., Mansonia altissima, Pterygota macrocarpa, Nesogordonia papaverifera, Sterculia rhinopetlal¸and Milicia excelsa. In the forest fragments in the Togo Hills, trees such as Antiaris Africana, Diospytos mespiliformis, Afzelia Africana, and Ceiba pentandra can also be found.
This ecoregion falls within the Upper Guinea forest block of the Guineo-Congolian regional center of endemism. Four small mammals are strictly endemic to this ecoregion: Wimmer's shrew, Ivory Coast rat, Cansdale's swamp rat, and the Togo mouse. The rare pygmy hippopotamus also occurs marginally in the western part of this ecoregion.
Small populations of African forest elephants also occur, often isolated in unconnected forest patches, and are relied upon by tree species, such as Tieghemella heckelii and Balanites wilsoniana, to facilitate their regeneration. The ecoregion contains high bird species richness, and shares several restricted range species with the Western Guinean Lowland Forests. Around 120 species of butterflies are believed to be endemic to the West African forest ecoregions as well as a number of butterflies that are narrowly endemic to the Togo Hills.
The forest cover has been reduced to a number fragmented remnant patches, found amongst large areas of agricultural land . These forests are mostly in protected areas under the control of national government wildlife or forestry departments. In Ghana, important protected areas include Kakum National Park, Bia National Park, Nini-Suhien National Park and Agumatsa Wildlife Sanctuary. There are also a large number of forest reserves that are used for timber production.
In Côte d’Ivoire, the largest remaining areas of forested habitats are found in the southeastern region in the Marahoue National Park and along the Comoé River, and in a number of forest reserves. The local human population also protect numerous small forest patches as sacred groves. In Ghana, there is estimated to be between 2,000 and 3,200 sacred groves; however, they have not been comprehensively mapped .
Forests have been lost in this region primarily due to slash-and-burn agriculture for the production of coffee and cocoa as well as commercial logging and fuelwood collection in unprotected forests due to burgeoning urban centres such as Abidjan and Accra. Additionally, logging of natural forest for valuable hardwoods such as iroko and mahogany has also contributed to the decline in forest area in all four countries in this ecoregion. Where forestry management authorities lack capacity, roads cut to access commercial hardwoods allow agriculturists and commercial hunters to penetrate further into the forests.
The impact of bushmeat hunting to meet the growing demand in urban and rural areas has already led to the extinction of a previously endemic primates, the Miss Waldron’s red colobus, and continue to threaten several endangered species.
The priority conservation actions for the next decade will be to: 1) enhance the level of forest and wildlife protection by upgrading managed areas to national parks, wildlife sanctuaries or reserves, e.g. supporting Ghana in their effort to legally protect areas by establishing Globally Significant Biodiversity Areas and Provenance Protection Areas; 2) support the development of forest management plans to achieve sustainable timber production; and 3) assist local communities to develop alternative livelihoods including mushroom farming.
1. Critical Ecosystem Partnership Fund. 2015. Ecosystem Profile: Guinean Forests of West Africa Biodiversity Hotspot.
2. White, F. 1983. The vegetation of Africa, a descriptive memoir to accompany the UNESCO/AETFAT/UNSO. United Nations Educational, Scientific and Cultural Organisation. Paris: France.
3. Nature & Development Foundation. 2018. Supporting the development of Forest Management Plans. [Online]. [Accessed 15 January 2018]. Available from: http://www.ndfwestafrica.org/list_of_projects/supporting-the-development-of-forest-management-plans/