The Okwangwo Division is the northern part of the Cross River National Park (CRNP), separated by about 50 km of disturbed rainforest from the southern Oban Division (NG007). It is located south-west of the Obudu Plateau (NG001) in south-eastern Nigeria and lies immediately east of Afi River Forest Reserve (NG005). It is bordered to the east by Takamanda Forest Reserve in Cameroon. The terrain comprises numerous ridge systems and rocky outcrops. Elevations reach 1,700 m in the Sankwala mountains in the north and about 1,000 m in the Mbe mountains in the south-west. The site is drained by the Oyi, Bemi and Okon rivers, all tributaries of the Cross river. Vegetation consists of two general types; lowland rainforest at lower elevations and montane grasslands (with relict forests in valleys) along high ridge-tops. Areas of derived savanna occur in lowland parts where there has been intense forest degradation. Soils of the lowland areas are ferralitic and highly susceptible to leaching, while those of the grassland areas are ferruginous and very easily eroded when exposed. The area has marked wet (March–November) and dry (December–February) seasons. Up to 4,280 mm of rain falls annually.
See Box and Tables 2 and 3 for key species. To date, over 280 species have been recorded including Picathartes oreas, which breeds in the Mbe mountains. Nationally uncommon species include Calyptocichla serina.
Non-bird biodiversity: With 18 species, Okwangwo has the highest diversity of primates recorded at a single site in Africa. Species include Pan troglodytes (VU), Gorilla gorilla (VU), Cercopithecus sclateri (EN), Cercopithecus preussi (EN) and Mandrillus leucophaeus (EN). Other large mammals include Loxodonta africana cyclotis (EN) and Syncerus caffer (LR/cd). Two species of Lepidoptera (Tetrarhanis okwango and T. ogojea) new to science have recently been described from the area. Plant diversity is high. A recent plant survey resulted in six first records for the country and four species possibly new to science.
BirdLife International (2019) Important Bird Areas factsheet: Cross River National Park (Okwangwo Division) and Mbe Mountains. Downloaded from http://www.birdlife.org on 20/11/2019.