The Guinean Forest Hotspot represents the Guinean portion of the Guinea-Congolian forests and contains two main blocks that incorporate several major Pleistocene refugia. The Upper Guinea Forest Ecosystem extends from Guinea into eastern Sierra Leone, and eastward through Liberia, Côte d'Ivoire and Ghana into western Togo. The Lower Guinea Forest Ecosystem extends from western Nigeria to the Sanaga River in southwestern Cameroon and also includes the islands of Bioko and Pagalu, both part of Equatorial Guinea, and São Tomé and Príncipe, which together are an independent nation. The two major ecosystems are separated by the Dahomey Gap, a mixture of savanna and dry forest, in Togo and Benin.
The Guinean Forest hotspot was originally covered in large part by tropical rainforest formations and extended an estimated 1,265,000 square kilometers. However, it has been dramatically reduced to a series of forest fragments separated by agricultural communities and degraded lands. Overall, the region retains approximately 141,000 square kilometers of closed canopy forest cover, or roughly 15% of its original vegetation, and only a little more than 20,000 square kilometers of the land area is found in national parks, nature reserves and wildlife sanctuaries that meet international standards for protection. It is important to note that, compared to the rest of this ecoregion, the Gulf of Guinea islands have higher percentages of their original forest cover intact, due largely to the inaccessibility of steep volcanic slopes that dominate these islands.
In terms of original extent, the Guinean Forest hotspot ranks fifth among the 25 hotspots identified by Conservation International (the top four are the Mediterranean Basin, Indo-Burma, the Brazilian Cerrado and Sundaland). Its ranking rises to fourth on the world list when only the area still intact is measured. In that category, it trails the Brazilian Cerrado, the Tropical Andes, and Mesoamerica. When one considers the land area currently under official protection, however, the Guinean Forests fall to 12th among the hotspots, suggesting that a great deal of work lies ahead to safeguard this region's biodiversity.
Aquatic systems, freshwater as well as coastal wetlands and near-shore marine communities, are clearly affected by upstream changes in terrestrial -and especially forested- environments. The north-south river systems that flow through the region show the impact of growing human populations, deforestation, expansion of commercial agriculture, and mining. Freshwater aquatic communities are not only heavily harvested -they are also degraded due to poor sanitation, siltation, and pollution. Furthermore, the capacity of rivers to support fisheries and coastal wetland and mangrove habitats is progressively weakened as they flow along their inland courses. Consequently, coastal habitats that are sustained by the ocean-bound freshwater flow are important not only for near-shore artisanal fishing but also for commercial marine fisheries, which are degraded. Marine turtles and manatees, as well as mangroves, wetland communities, and important sites for migratory shorebirds and waterfowl, are still found along the coasts, but receive limited protection. In addition to the challenges created by prevailing land use along watercourses, the conservation of aquatic systems and watersheds is often complicated by their transnational character, reflecting the impact of political fragmentation on the West African landscape.
Approximately 9,000 species of vascular plants are estimated to occur in the Guinean Forest Hotspot, which ranks it eighth among the hotspots along with the Chocó-Darién/Western Ecuador. Of the plants, 2,250 (25%) are believed to be endemic, suggesting a global ranking of 15th in the number of endemic species (again along with the Chocó-Darién/Western Ecuador), and a ranking below median among hotspots with respect to the percentage of endemics (Wallacea Hotspot has a 15% rate of plant endemism; the Madagascar and Indian Ocean Islands Hotspot and New Zealand Hotspot have rates of 81%). On average, there are 71 species of vascular plants for every square kilometer of intact natural vegetation in the Guinean Forest Hotspot. This falls in the bottom fifth of the hotspots, the low being 28 species per square kilometer for the Brazilian Cerrado and the high being a remarkable 2,000 species per square kilometer in the Eastern Arc Mountains and Coastal Forests of Kenya and Tanzania. The number of endemic plants per square kilometer, approximately 18, is also on the lower end of the scale with the least being 12 for the Brazilian Cerrado and the greatest being approximately 700, for the Eastern Arc Mountains and Coastal Forests.
Hotspot rankings aside, another global analysis conducted on centers of plant diversity and endemism has identified 14 centers of plant endemism within the Guinean Forest Hotspot: Taï National Park in Côte d'Ivoire, Southeast Forest Remnants in Côte d'Ivoire, Southeast Ghana, Mount Nimba on the Liberia-Guinea-Côte d'Ivoire border, the Cestos-Senkwen River Area in Liberia, Lofa-Mano in Liberia, Sapo National Park in Liberia, the Gola Forests in Sierra Leone, Loma in Sierra Leone, the Cross River National Park in Nigeria, Korup National Park in Cameroon, Mount Cameroon, Príncipe, and São Tomé. These should be considered in the assessment of focal areas for biodiversity conservation within the hotspot.
Levels of faunal diversity and endemism in the Guinean Forests are also impressive. Mammalian diversity, with 551 species, ranks first among the world's 25 hotspots and represents almost half of the 1,150 mammals that are native to continental Africa. Of the Guinean Forests' 551 mammals, 45 (8%) are endemic, a global ranking of 13th in terms of number and a relatively low percentage. At 4.3 mammal species per square kilometer of intact natural vegetation, the Guinean Forest Hotspot ranks an impressive seventh on the world list. However, as suggested by the figures for endemism, the ratio of endemic mammals to remaining intact natural vegetation is also on the lower end of the global scale at 0.3 per square kilometer.
Based on the Guinean Forest's rank as the world's foremost hotspot for mammalian diversity, combined with the relatively high number of species per unit area of intact natural vegetation and the large area of such vegetation that remains unprotected, it is clear that the single highest global priority for mammal conservation must be an increase in the size and number of protected areas within this region. The forest elephant (
Loxodonta africana cyclotis) and bongo (Boocerus euryceros) have emerged as important flagship species for conservation in the Guinean region and beyond, as have Guinean endemics such as the pygmy hippopotamus (
Hexaprotodon liberiensis), several species of forest duikers (
Cephalophus jentinki,
C. maxwelli,
C. niger,
C. zebra) and a host of highly endangered primate species and subspecies.
The status of the Guinean Forest primates, in fact, ranks it with the Indo-Burma Hotspot among the two highest-priority regions for primate conservation. According to the 2000 IUCN Red List of Threatened Species, five primates are critically endangered: the white-collared mangabey (
Cercocebus atys lunulatus), Roloway monkey (
Cercopithecus diana roloway), Stampfl's putty-nosed guenon (
Cercopithecus nictitans stampflii), Miss Waldron's red colobus (
Procolobus badius waldroni), and the Cross River gorilla (
Gorilla gorilla diehli). Another 21 primates are considered endangered. All but the last two of these threatened primates, or 92%, are endemic to the Guinean Forests Hotspot, and at least one, Miss Waldron's red colobus, has not been sighted in over a quarter of a century and is suspected to be extinct. By far the most important centers for primate diversity, endemism and threat are the island of Bioko, the Nigeria-Cameroon border, and the forests of southwestern Ghana-southeastern Côte d'Ivoire.
Birds also exhibit significant levels of diversity and endemism in the Guinean Forest Hotspot, with 514 species (14th among the hotspots) and 90 (18%) endemics (10th among the hotspots in number and a significant percentage). The figures for bird diversity (4.1 species per square kilometer) and endemism (0.7 endemic species per square kilometer) per unit area of intact vegetation, while not singularly impressive, still help to establish this region among the global priorities for avian conservation. BirdLife International recognizes six Endemic Bird Areas partly or entirely within the Guinean Forest Hotspot: the Upper Guinean Forests, with 15 restricted-range and 11 threatened species; the Cameroon Mountains (which extend into Nigeria and also include the island of Bioko) with 29 restricted-range and 12 threatened species; the Cameroon and Gabon Lowlands with six restricted-range and two threatened species; the island of São Tomé with 21 restricted-range and eight threatened species; the island of Príncipe with 11 restricted-range and two threatened species; and the island Annobón (also Pagalu) with three restricted-range and two threatened species. Clearly, the Upper Guinean Forests, Cameroon Mountains and Gulf of Guinea islands emerge as high global priorities for avian priorities within this region.
Among the birds, important flagship species for tropical forest conservation in the Upper Guinean Forests include the white-breasted guinea fowl (
Agelastes meleagrides), white-necked rockfowl (
Picathartes gymnocephalus), rufous fishing owl (
Scotopelia ussheri), Liberian greenbul (
Phyllastrephus leucolepis), Nimba flycatcher (
Malaenornis annamarulae) and the Gola malimbe (
Malimbus ballmanni). On the island of São Tomé, three endemic and critically endangered species can be added to the list of conservation flagships: the dwarf olive ibis (
Bostrychia bocagei), the São Tomé fiscal (
Lanius newtonii) and São Tomé grosbeak (
Neospiza concolor).
Of the region's terrestrial vertebrates, we know least about reptile and amphibian diversity. Minimum species estimates for each class are 139 and 116, respectively, but these should be regarded as preliminary. Levels of endemism within the known herpetological faunas are relatively high, however, with 46 species of reptile (33%) and 89 species of amphibian (77%) found only with the Guinean Forest Hotspot. While none of these figures place the Guinean Forests among the highest priority hotspots for reptile and amphibian conservation, the fact that we know relatively little about the levels of diversity and endemism for these vertebrate classes in this region establishes more extensive zoological research as a clear priority.
In terms of non-fish vertebrate diversity, West Africa's Guinean forests rank an impressive eighth among the world's hotspots, with 1,320 species, very similar to the level observed in Brazil's Atlantic Forest region. In terms of non-fish vertebrate endemism, the Guinean Forests rank 12th among the hotspots, with 270 endemic species or about 20% endemism. Given the relatively large area of intact natural vegetation, ratios of vertebrate diversity and endemism to area are relatively low compared to other hotspots, but this again points to the need to expand the total area of natural habitat under formal protection in order to safeguard this regions biodiversity.
The consensus recommendations of the Conservation Priority-setting Workshop underscore the need to strengthen and expand national protected areas and the systems that support them across the region. While some ambitious plans are being developed and pursued in several countries for reform of the protected area systems, protection in existing areas is not viable at current funding and capacity levels. Existing protected areas within the Guinean Forest Hotspot are listed in the table below. The degree to which they include natural intact vegetation is not known at present, nor is the degree to which levels of biodiversity and endemism are represented within these collective national parks, nature reserves and wildlife sanctuaries. However, responding to the extinction crisis resulting from the bushmeat trade, a recent analysis of primate conservation efforts within the hotspots has identified a number of these protected areas as especially high priorities for the Guinean Forest region. (In the table, these are indicated by an asterisk.)
| Country |
Protected Area |
Area (km2) |
| Guinea |
Massif du Ziama Strict Nature Reserve |
1,123 |
| Mount Nimba Strict Nature Reserve |
130 |
| Sierra Leone |
Tiwai Island Game Reserve * |
12 |
| Outamba-Kilimi National Park |
808 |
| Gola Forest Nature Reserves * |
176 |
| Liberia |
Sapo National Park * |
1,307 |
| Côte d'Ivoire |
Azagny National Park |
190 |
| Banco National Park |
340 |
| Iles Ehotile National Park |
105 |
| Marahoue National Park * |
1,010 |
| Mount Peko National Park |
340 |
| Mount Sangbe National Park |
950 |
| Tai National Park * |
3,500 |
| Mount Nimba Strict Nature Reserve |
50 |
| Ghana |
Bia National Park * |
78 |
| Digya National Park |
3,478 |
| Kakum National Park |
207 |
| Nini-Suhien National Park * |
160 |
| Kogyae Strict Nature Reserve |
386 |
| Bomfobiri Wildlife Sanctuary |
53 |
| Owabi Wildlife Sanctuary |
13 |
| Nigeria |
Cross River National Park * |
4,000 |
| Cameroon |
Korup National Park * |
1,259 |
| Equatorial Guinea |
Pico Basile National Park |
350 |
| Southern Highlands National Park * |
600 |
| TOTAL |
20,625 |
* Identified as a high priority protected area for primate conservation.
Many of the 41 consensus priority areas identified by the experts fall outside of strict protected areas, some within a variety of classifications of management including faunal and forest reserves (or proposed protected areas). Still others fall entirely outside any protection or management regime. According to Conservation International's hotspot analysis, approximately 141,000 square kilometers (roughly 15%) of the Guinean Forest hotspot retains its natural vegetation intact (Fig.2). It is also important to note that only about 20,000 square kilometers of the hotspot can be found in Strict Nature Reserves and other protected areas, which represents less than 2% of the hotspot's original extent. This is well below the level of habitat protection recorded for the hotspots, which averages 40% of the natural vegetation intact.
Recommendations from the CPW include a priority emphasis on implementing the plans to establish the protected area system in Liberia, particularly in the northwest and southeast. Furthermore, experts encouraged initiatives such as those underway by Ghana to establish Globally Significant Biodiversity Areas. In many cases, recommendations include upgrading managed areas to national parks, nature reserves or wildlife sanctuaries and increasing levels of protection of resident biodiversity.
Previous: Background / Next: Threat Assessment