Bight of Benin and Niger Delta, Part 2: Mangroves and Grasslands

Central African Mangroves

This ecoregion is found in Ghana (Greater Accra and Volta Regions) and Nigeria (Lagos, Ogun, Ondo, Edo, Delta, Bayelsa, and Akuwa Ibom States). The coastline of west Africa is a complex network of rivers, estuarine swamps, and barrier islands. In Nigeria, flood tides can penetrate as much as 45 km inland. Mangroves form in these coastal areas, including in the deltas of the Volga and Niger Rivers, as well as in the area around lagoons in coastal Nigeria such as around Lagos. Mangrove swamps capture the sediment load coming from rivers in the Niger and Volta deltas. Three species of red mangrove and two species of white mangrove dominate. The trees provide habitat for the African manatee, soft-skinned turtle, and pygmy hippopotamus.

World Heritage Site

Fort Prinzenstein, Volta Region, Ghana (N5o55’ E0o59’) was constructed in 1784 by Danish traders and used in the slave trade. It is part of the Forts and Castles of Ghana World Heritage listing.

Ramsar sites

Apoi Creek Forest Reserve, Bayelsa State, Nigeria (N4o42’ E5o47’) is a 29,213-ha lowland tidal freshwater swamp forest, known for red colobus monkey.

Keta Lagoon Complex, Volta Region, Ghana (N5o55’ E0o59’), is 3,000 ha noted for migratory birds, Nile monitor, West African manatee, and sea turtle nesting. It is the eastern part of the Volta River estuary. It is an Important Bird Area, the most important wetland in Ghana for water birds.

Songor Lagoon Complex, Accra Region, Ghana (N5o50’ E0o28’) is 51,113 ha in the western part of the Volta River estuary. It contains an estuary, sandy beaches, and floodplain habitats. It is also a Man and the Biosphere Reserve and Important Bird Area.

Other sites

Akassa forests, Bayelsa State, Nigeria (N4o21’ E5o59’) is a lowland forest and mangrove area near the coast in the Niger Delta.

Edumanon Forest Reserve, Bayelsa State, Nigeria (N4o25’ E6o27’) is 86,760 ha east of the Niger River. The freshwater swamp area is known for chimpanzees, manatee, and three species of crocodile (Akani et al., 2014a).

Finima Nature Park, Rivers State (N4o24’ E7o11’) is 1,000 ha on Bonny River managed by the Nigerian Conservation Foundation with funding from the Nigeria Liquefied Natural Gas Company.

Lekki Conservation Centre, Lagos State (N6o26’ E3o32’) is 78 ha in the urban area of Lagos. The Nigerian Conservation Foundation manages the site, which features a canopy walkway.

Tropical and Subtropical Grasslands

Guinean forest-savanna

This ecoregion is a humid tropical savanna just to the north of the equatorial rain forests of Africa. Rains occur during a single rainy season of 5 to 7 months in the north. In the south, two rainy seasons of two to four months are separated by a dry period in July or August. The Dahomey Gap portion of this ecoregion, found in Benin, Togo, and Ghana, stretches south to the Atlantic Ocean at the Bight of Benin and separates the rainforests in Ghana from those in the Congo region to the east. The topography is gently rolling plains with scattered isolated mountains rising to 1,500 m. Forest patches include species from nearby rainforests to the east, west, and south. Grasses are generally tall grasses except for short grasses in the Dahomey Gap. Animals include the African palm civit, lesser spot-nosed monkey, and Maxwell’s duiker. Savanna species include baboon, common duiker, helmeted Guinea fowl, and side-striped jackal. Mathey’s mouse and Jackson’s fat mouse are endemic mammals to this ecoregion. The ecoregion is found in Benin (Collines, Zou, Plateau, Kouffo, Mono, Atlantic, and Queme), Ghana (Volta), Nigeria (Ogun, Oyo, Kwara, Kogi, Ekiti, Ondo, Edo, Niger, Federal Capital Territory, Kaduna, Nassarawa, Benue, Enugu, Ebony, Anambra).

World Heritage Sites

Royal Palaces of Abomey, Zou Department, Benin (N7o11’ E2o0’) is 47 ha containing 10 palaces of the Kingdom of Abomey. The kingdom existed from 1625 to 1900 and 12 kings lived in the area until it was conquered by France in 1900. The empire derived its wealth from trading prisoners of war as slaves with European merchants. In lieu of written documents, decorative bas reliefs were used on walls, illustrating the most significant events in the evolution of the empire.

Fort Fredensborg, Greater Accra Region, Ghana (N5o45’ E0o11’), was a Danish Fort constructed in 1734 in present-day Old Ningo. It is part of the Forts and Castles of Ghana World Heritage Site.

Fort Vernon, Greater Accra Region, Ghana (N5o43’ E0o7’) was constructed in 1742 by the British in present-day Prampram. It was used in the slave trade. It is part of the Forts and Castles of Ghana World Heritage Site.

Ramsar Sites

Lower Couffo Valley, Coastal Lagoons, Aho Channel, and Aheme Lake (Bassee Vallee du Couffo, Lagune Cotiere, Chenal Aho, and Lac Aheme) Ramsar Site, Benin (N6o47’ E1o51’), is 524,289 ha of mangroves, flooded grasslands, and wooded savanna, including the valleys of the Couffo, Mono, and Sazue Rivers. The site includes the Mono Biosphere Reserve. Aheme Lake and Aho are Important Bird Areas.

Lower Kaduna-Middle Niger flood plain Ramsar Site, Niger and Kwara States, Nigeria (N8o50’ E5o50’) is 229,054 ha containing swamp forests and savanna woodland. Trees include Uapaca togoensis (Phyllanthaceae), Berlinea (Fabaceae), Pterocarpus (Fabaceae), Terminalia (Combretaceae), and Diospyros (Ebenaceae). The area is an important Bird Area for colonies of the rosy bee-eater.

Lower Oueme, Porto Novo Lagoon, and Lake Nokoue (Basse Vallee de l’Oueme, Lagune du Porto Novo, Lac Nokoue) Ramsar Site, Benin, is 652,670 ha of swamp forest, flooded grassland, reeds, and mangroves harboring 8 primates, aquatic mammals, the leatherback turtle, and 215 birds. Lake Nokoue (N6o25’ E2o25’) is an Important Bird Area. The old lagoons (N6o35’ E2o11’) are west of Lake Nokkoue. The lower Oueme Valley (N6o27’ E2o30’) includes the capital of Cotonou, the Oueme and So River floodplains, and the Lake Nokoue area. Brackish water is found in Nokaue Lake and the Porto Novo lagoon. Swamp forests and relict mangroves are present. Lake Nokoue contains a rich fish fauna and is noted for the black tern. It is an Important Bird Area. The Middle Oueme Valley (N6o50’ E2o40’) has mostly been converted to oil palm and teak plantations but relict Celtis (Cannabaceae), Milicia (Moraceae), and Ceiba (Malvaceae) forests are present. The Adjarra swamps (N6o44’ E2o40’) are east of the river and include marshy grasslands and estuaries of the Porto Novo plateau. Islands of humid and swamp forest are present. Coastal and nearshore oceanic areas are also included in the Ramsar site.

Padam and Wise Lakes Wildlife Park, Plateau State, Nigeria (N8o42’ E8o58’) includes 217 bird species such as the white-faced whistling duck and the long-toed lapwing.

Songor Lagoon Complex, Accra Region, Ghana (N5o50’ E0o28’) is 51,113 ha in the western part of the Volta River delta. It contains mudflats, islands, sandy beaches, and floodplain habitats. Also included are saline marshes, wet grassland, and riverine woodland. Birds include herons, egrets, greenshank, avocet, and stilts. Beaches are known for sea turtle nesting; the three species involved are leatherback, olive ridley, and green turtle. Threats to nesting are trawling vessels, poaching from the nesting beach, egg predation by dogs and humans, and hatchling predation by mammals and birds (Agyeman, Riverson, and Andrews, 2013). It is also a Man and the Biosphere Reserve. Songor is a community-owned reserve where the lagoon and estuary are owned by clans. The elders serve as custodians. People in the reserve are involved in subsistence crop farming, animal rearing, fishing, hunting, salt mining, and fuel wood collection. There are several sacred groves (Ashong et al., 2013). It is also a Man and the Biosphere Reserve and an Important Bird Area, especially for terns, herons, and egrets.

Togodo Faunal Reserve, Maritime and Plateaux Districts, Togo (N6o49’ E1o25’), is 31,000 ha, consisting of semi-deciduous forest with ponds and swamps. It is included in the Mono Transboundary Biosphere Reserve.

Biosphere Reserves

Mono Transboundary Biosphere Reserve is 346,286 ha on the lower Mono River in Benin and Togo. The alluvial plain of the Mono River contains savanna, mangroves, and lagoons hosting dugong and hippos. Sites included in the reserve are Bouche du Roy, Benin (N6o18’ E1o52’); Lake Toho (N6o37’ E1o42’), Hadjivi Island Naglanou Forest Complex (N6o33’ E1o42’), the complex of Adjamey (N6o50’ E1o37’), the Togodo Faunal Reserve (N6o49’ E1o25’), Lakes of Afito (N6o46’ E1o36’), the Sacred Forest of Godje-Godjin, the Sacred Forest of Akissa (N6o19’ E1o47’), and the Lake Togo-Gbaga Channel Complex (N6o15’ E1o25’). Financial assistance for reserve management is provided by the German Federal Environment Ministry. The Benin portion is also included in the Lower Couffo Valley, Coastal Lagoons, Aho Channel, and Aheme Lake Ramsar Site.

Songor Lagoon Complex Biosphere Reserve is listed above under Ramsar sites.

Other sites

Digya National Park, Bono East Region, Ghana (N7o26’ E0o0’) is 347,800 ha on the west side of Volta Lake. The park contains isolated mountains, Guinea savanna woodland, 6 primates, elephants, antelopes, manatees, and otters.

Kainji National Park, Niger State, Nigeria is a 534,000-ha important Bird Area in two large tracts. Borgu Sector (N10o0’ E4o0’) is west of the Niger River and Zugurma Sector (N9o40’ E5o0’) is east. The Borgu sector and Kainji lake are in the West Sudanian Savanna ecoregion. The Zugurma sector is in the Guinean forest-savanna ecoregion. The shores of Kainji Lake are a wintering area for migratory birds. Numerous antelope species are also present.

Kalakpa Game Production Reserve, Volta Region, Ghana (N6o29’ E0o29’) is in the foothills of the Togo Mountains. Habitats are dry forest and short grass savanna. Animals found in the reserve include lions, elephants, buffalo, antelope, and red river hog, along with 148 bird species and 227 butterfly species.

Farin Ruma Falls, Nasarawa (N9o9’ E8o45’) is a 150-m waterfall.

Keana Salt Village, Nasarawa state (N8o8’ E8o48’) is a salt mining town dating to the 12th century.

Lama Forest Reserve, Atlantique and Zou Districts, Benin (N6o57’ E2o8’) is 16,250 ha in an east-west oriented depression and an Important Bird Area. Forests are of Afzelia (Fabaceae), Bombax (Malvaceae), Ceiba (Malvaceae), and Parinari (Chrysobalanceae).

Matsirga Waterfalls, Kaduna State (N9o33’ E8o14’) are 30 m in height near Kafanchan.

Mount Patti, Lokoja, Kogi State (N7o49’ E6o43’) is a 458-m flat-topped mountain that overlooks the confluence of the Niger and Benue Rivers. It is popular hiking spot and the location of Lord Lugard’s rest house, a colonial-era structure on the mountain.

Old Oyo National Park, Oyo State, Nigeria (N5o25’ E3o50’), is 2.5 million ha of savanna in both the Guinean forest-savanna and West Sudanian savanna ecoregions. The park contains the ruins of the Oyo Empire’s capital city (Oyo). Topography ranges from lowland plains to granite outcrops.

Peperuwa (Feferuwa) Lake, Nawarawa (N8o39’ E8o50’) is known for hippos and waterfowl.

Sunvit Farm, Edo State, Nigeria (N7o7’ E6o41’) is 13,200 ha of Guinean savanna and riparian forests, bordered by the Ogbudu and Obe Rivers. It is an Important Bird Area.

Shai Hills Resource Reserve, Greater Accra Region, Ghana (N5o55’ E0o4’) is 5,100 ha of grassland and dry forest on granitic hills, housing baboons, green monkeys, antelope, and zebra. It is an Important Bird Area.

West Sudanian savanna

The ecoregion has a distinct dry season that lasts from 6 months in the south to 9 months in the north. Grasses in these areas range from tall grasses in the south to short grasses in the north.  The vegetation consists of woodland ranging from 10 percent coverage in the north to 40 percent canopy coverage in the south. with an understory of long grasses, shrubs, and herbs. Common woody plant families are the Combretaceae and Fabaceae, with common genera Acacia (Fabaceae), Combretum (Combretaceae), and Terminalia (Combretaceae). Along streams and rivers, plants from the more humid Guinean forest-savanna are able to survive. Animals include bushbuck, warthog, vervet monkey, baboon, and savanna monitor lizard. In protected areas, elephant, hippopotamus, roan antelope, and western persist. The ecoregion is found in Benin (Borgou, Collines, Donga), Ghana (Northern, Oti, Volta), Nigeria (Kwara, Niger, Oyo), and Togo (Savannes, Kara, Central, Plateaux.

Abdoulaye Faunal Reserve, Centrale Region, Togo (N8o39’ E1o22’), is representative of the West Sudanian savanna. A plant study indicated 258 plant species, of which 67 were woody. Dominant plant families were Combretaceae, Sapotaceae, and Fabaceae. Dominant woody genera were Anogeissus (Combretaceae), Pouteria (Sapotaceae), Cola (Malvaceae), Diospyros (Ebenaceae), and Dialium (Fabaceae) (Periki et al., 2013).

Fazao-Malfakassa National Park, Centrale and Kara Regions, Togo (N8o50’ E0o45’) includes 192,000 ha of forest patches of the Eastern Guinean forests (Dialium (Fabaceae), Antiaris (Moraceae), Berlinia (Fabaceae)) and lower elevation areas in the West Sudanian savanna (Afzelia (Fabaceae), Anogeisseus (Combretaceae), and Isoberlinia (Fabaceae)). Peaks that dominate the park are Mount Fazao in the center and Mount Malfakassa in the north. Some areas have precipitous cliffs. The Kamassi River drains the park. Between 1987 and 2015 the area of closed canopy forest in the park decreased 40 percent, suggesting overexploitation by local populations due to agricultural expansion, bushfires, and timbering (Atsri et al., 2018). The park is an applicant for Biosphere Reserve status. More than 200 bird species have been recorded in the park, including the white-browed forest flycatcher (Radley and Campbell, 2008).

Kainji National Park, Niger State, Nigeria is a 534,000-ha important Bird Area in two large tracts. Borgu Sector (N10o0’ E4o0’) is west of the Niger River and Zugurma Sector (N9o40’ E 5o0’) is east. The Borgu sector and Kainji lake are in the West Sudanian Savanna ecoregion. The Zugurma sector is in the Guinean forest-savanna ecoregion. The shores of Kainji Lake are a wintering area for migratory birds. Numerous antelope species are also present.

Monts Kouffe Forest Reserve, Donga Department, Benin (N8o45’ E2o6’) is 180,300 ha and part of the Oueme River Basin Important Bird Area

Old Oyo National Park, Oyo State, Nigeria (N5o25’ E3o50’), is 2.5 million ha of savanna in both the West Sudanian savanna and Guinean forest-savanna ecoregions. The park contains the ruins of the Oyo Empire’s capital city (Oyo). Topography ranges from lowland plains to granite outcrops.

Ouari-Maro Forest Reserve, Borgou Department, Benin (N9o9’ E2o25’) is 107,500 ha and part of the Oueme River Basin Important Bird Area

Oueme Superieur Forest Reserve, Borgou Department, Benin (N9o35’ E2o30’) is 177,542 ha and part of the Oueme River Basin Important Bird Area.

Sources

Sheila N.A. Ashong et al. 2013. Natural Resources, People, and Livelihoods in the Songor Biosphere Reserve. Pp. 123-140 In Ruida Pool-Stanvliet and Miguel Closener-Godt. AfriMAB, Biosphere Reserves in Sub-Saharan Africa: Showcasing Sustainable Development. Republic of South Africa, Department of Environmental Affairs, and United Nations Educational Scientific and Cultural Organization.

Honam Komina Atsri et al. 2018. Changes in the West African forest-savanna mosaic, insights from Central Togo. PLoS ONE 13(10):e0203999. DOI: 10.1371/journal/pone.0203999.

Neil Burgess, Jennifer D’Amico Hales, Emma Underwood, Eric Dinerstein, David Olson, Illanga Itoua, Jan Schipper, Taylor Ricketts, and Kate Newman. 2004. Terrestrial Ecoregions of Africa and Madagascar: A Conservation Assessment. Island Press.

Hodabalo Periki et al. 2013. Woody species diversity and important value indices in dense dry forests in Abdoulaye Wildlife Reserve (Togo, West Africa). International Journal of Biodiversity and Conservation 5:358-366. DOI: 10.5897/IJBC12.061.

Paul M. Radley and Genevieve Campbell. 2008. The birds of Fazao-Malfakassa National Park, including a first record for Togo of white-browed forest flycatcher Fraseria cinerascens. African Bird Club Bulletin 15:203-213.