The Atewa Range (also called the Atiwa-Atwaredu ranges) is in the Akyem Abuakwa region of southeastern Ghana, near the town of Kibi, and south-west of the Kwahu Plateau which forms the south-west boundary of Lake Volta. The range runs roughly north-south, consisting of steep-sided hills with fairly flat summits. It is the last remains of the Tertiary peneplain that once covered southern Ghana, and contains ancient bauxitic soils. The range is the site of an important forest reserve, and the source of three major rivers.
Giant African Swallowtail (Papilio antimachus)
A large area of the range has been declared a forest reserve, including about 17,400 hectares of upland evergreen forest, rare for Ghana. The reserve is managed by the Okyeman Environment Foundation, which has restricted people from farming in the area and instead is trying to encourage eco-tourism. However, the reserve is under pressure from logging and hunting for bushmeat. It may also be vulnerable to mining exploration activities, since the reserve contains gold deposits as well as low-grade bauxite.
Many of the plant species occur only in this part of Ghana. The forest reserve contains many birds that are rare elsewhere in Ghana including Afep Pigeon, Olive Long-tailed Cuckoo, African Broadbill, Least Honeyguide, Spotted Honeyguide, Common Bristlebill and Blue-headed Crested-flycatcher. In a 2006 expedition to survey the reserve, scientists discovered two rare and possibly endangered species of primate in the reserve: Geoffroy’s pied colobus (Colobus vellerosus) and the olive colobus (Procolobus verus), as well as 17 rare butterfly species and the critically endangered frog species Conraua derooi. Butterfly species include the Papilio antimachus, which has the widest wingspan in the world and the Mylothris atewa, which may be globally critically endangered.
The Atewa range is the source of three important rivers: the Ayensu and Densu which flow south into the Atlantic, and the Birim which makes a long detour north and southwest around the Atewa range before joining the Pra River. The Birim, which flows through all the three of the traditional Akyem areas of Ghana, is an important but declining source of diamonds.