Biodiversity and Protected Areas in West Africa
Biological diversity, or biodiversity, can be defined as the full array of life in a region, including species richness, ecosystem complexity, and genetic variation. Biodiversity may be the greatest natural resource, as it is a source of food, fuel, medicines, clothing, building materials, clean water, tourism and many other benefits (Norse and others, 1986). Biodiversity possesses marked economic value that in many areas enables conservation to serve as a competitive form of land use (Stock, 2012).
Biodiversity’s importance in West Africa is well established. The various ecosystems, ranging from dry savanna to tropical forest, provide habitats to more than 2,000 amphibian, bird and mammal species (IUCN, 2015). The region’s tropical forest, in the Upper Guinean countries, is the main locus for biodiversity. These lowland forests of West Africa are home to 320 mammal species (which represents more than a quarter of Africa's mammals), 9,000 vascular plant species, and 785 bird species (Conservation International, 2008). The Upper Guinean forest is renowned for its primate diversity, with nearly 30 distinct species, and has been identified as some of Africa's most critical primate conservation area. The West African forest ecosystem is also home for two of Africa's great apes, including remaining scattered populations of the endangered western chimpanzees and a small population of western lowland gorillas on the Nigeria-Cameroon border. The West African countries are also home to a population of over 7,500 African elephants, although many groups reside in northern savannah habitats outside the forest ecosystems (Mallon and others, 2015). The Upper Guinean forest ecosystem of West Africa, however, is one of the most critically fragmented regions on the planet. Logging, mining, hunting and human population growth are placing extreme stress on the forests threatening species such as the Jentinka's duiker or the pygmy hippopotamus (Conservation International, 2008). Indeed, only 69,424 sq km, or 10 percent of its original dense forest cover remains. Much of this remaining forest is exploited for timber and does not represent intact habitat. Moreover, hunting and indiscriminate trapping are prevalent throughout the forest zone and accelerating harvest rates put increasing pressure on populations of primates and forest antelopes in particular. Similarly, hunting whether for meat, trophies or sport, has resulted in a catastrophic decline of large mammals across the Sahel and Sahara zones in the north of the region (Durant and others, 2014; Mallon and others, 2015). The reduced prey base adversely impacts carnivore numbers, such as the African lion, across the region.
In West Africa today, most of the endangered species and highly biodiverse habitats are confined to protected areas. A total of 1,936 nationally protected areas have been identified in the region, currently covering around 9.6 percent of West Africa (see Protected Areas map above). Approximately 90 percent of these protected areas are small and dominated by forest reserves. In addition, 53 protected areas have international designations, including 17 Biosphere Reserves. Protected areas vary widely in size, from less than 1 sq km to 97,300 sq km. However, large protected areas, including clusters of sites, are critical to supporting viable populations of larger species or to ensure fully-functioning, dynamic ecosystems (Mallon and others, 2015). More extensive areas or buffer zones provide connectivity between habitats, safeguard dispersal corridors between core populations and natural migration routes, and enhance resilience to the effects of climate change (Mengue-Medou, 2002). Since international borders rarely coincide with ecosystem boundaries, transboundary sites and landscapes are of great importance. These better preserve ecosystem function, show the value of managing biodiversity conservation at a sub-regional in spite of institutional difficulties, engage local communities, and may lead to harmonization of legislation. For instance, Diawling National Park in Mauritania and Djoudj Bird Reserve in Senegal lie on opposite sides of the Senegal River Delta but the joint site is recognized as an International Biosphere Reserve. Similarly, the W-Arly-Pendjari complex (Benin, Burkina Faso and Niger) is a transboundary Biosphere Reserve which covers roughly 32,250 sq km, and protects a highly biodiverse savanna ecosystem.
Landscapes of West Africa: A Window on a Changing World
Biological diversity, or biodiversity, can be defined as the full array of life in a region, including species richness, ecosystem complexity, and genetic variation. Biodiversity may be the greatest natural resource, as it is a source of food, fuel, medicines, clothing, building materials, clean water, tourism and many other benefits (Norse and others, 1986). Biodiversity possesses marked economic value that in many areas enables conservation to serve as a competitive form of land use (Stock, 2012).
Biodiversity’s importance in West Africa is well established. The various ecosystems, ranging from dry savanna to tropical forest, provide habitats to more than 2,000 amphibian, bird and mammal species (IUCN, 2015). The region’s tropical forest, in the Upper Guinean countries, is the main locus for biodiversity. These lowland forests of West Africa are home to 320 mammal species (which represents more than a quarter of Africa's mammals), 9,000 vascular plant species, and 785 bird species (Conservation International, 2008). The Upper Guinean forest is renowned for its primate diversity, with nearly 30 distinct species, and has been identified as some of Africa's most critical primate conservation area. The West African forest ecosystem is also home for two of Africa's great apes, including remaining scattered populations of the endangered western chimpanzees and a small population of western lowland gorillas on the Nigeria-Cameroon border. The West African countries are also home to a population of over 7,500 African elephants, although many groups reside in northern savannah habitats outside the forest ecosystems (Mallon and others, 2015). The Upper Guinean forest ecosystem of West Africa, however, is one of the most critically fragmented regions on the planet. Logging, mining, hunting and human population growth are placing extreme stress on the forests threatening species such as the Jentinka's duiker or the pygmy hippopotamus (Conservation International, 2008). Indeed, only 69,424 sq km, or 10 percent of its original dense forest cover remains. Much of this remaining forest is exploited for timber and does not represent intact habitat. Moreover, hunting and indiscriminate trapping are prevalent throughout the forest zone and accelerating harvest rates put increasing pressure on populations of primates and forest antelopes in particular. Similarly, hunting whether for meat, trophies or sport, has resulted in a catastrophic decline of large mammals across the Sahel and Sahara zones in the north of the region (Durant and others, 2014; Mallon and others, 2015). The reduced prey base adversely impacts carnivore numbers, such as the African lion, across the region.
In West Africa today, most of the endangered species and highly biodiverse habitats are confined to protected areas. A total of 1,936 nationally protected areas have been identified in the region, currently covering around 9.6 percent of West Africa (see Protected Areas map above). Approximately 90 percent of these protected areas are small and dominated by forest reserves. In addition, 53 protected areas have international designations, including 17 Biosphere Reserves. Protected areas vary widely in size, from less than 1 sq km to 97,300 sq km. However, large protected areas, including clusters of sites, are critical to supporting viable populations of larger species or to ensure fully-functioning, dynamic ecosystems (Mallon and others, 2015). More extensive areas or buffer zones provide connectivity between habitats, safeguard dispersal corridors between core populations and natural migration routes, and enhance resilience to the effects of climate change (Mengue-Medou, 2002). Since international borders rarely coincide with ecosystem boundaries, transboundary sites and landscapes are of great importance. These better preserve ecosystem function, show the value of managing biodiversity conservation at a sub-regional in spite of institutional difficulties, engage local communities, and may lead to harmonization of legislation. For instance, Diawling National Park in Mauritania and Djoudj Bird Reserve in Senegal lie on opposite sides of the Senegal River Delta but the joint site is recognized as an International Biosphere Reserve. Similarly, the W-Arly-Pendjari complex (Benin, Burkina Faso and Niger) is a transboundary Biosphere Reserve which covers roughly 32,250 sq km, and protects a highly biodiverse savanna ecosystem.