Kakamega Forest

Description

Kakamega Forest is a mid-altitude tropical rainforest, the easternmost outlier of the Congo Basin forests. Its West African affinities are unique in Kenya, and the forest contains many species found nowhere else in the country. The forest lies in the Lake Victoria catchment, about 40 km north of Kisumu, and just west of the Nandi Escarpment that forms the edge of the central highlands.

Kakamega forest was first gazetted as Trust Forest in 1933, and two small Nature Reserves, Yala and Isecheno (totaling about 700 ha), were established within the Forest Reserve in 1967. In 1986, nearly 4,000 hectares of the northern portion of the forest, along with the adjacent 457 hectares Kisere Forest, were gazetted as a National Park, Kakamega Forest is an important catchment; the Isiukhu and Yala Rivers flow through the forest and gather tributaries from it. The terrain is undulating, with often steep-sided river valleys. The soils are well-drained, deep, heavily leached clay-loams and clays, of generally low fertility. Rainfall is approximately 2,001mm per year, decreasing from south to north, and apparently declining due to deforestation.

Wildlife in the area

The forest holds large populations of black-and-white colobus monkey (Colobus guereza) and red-tailed monkey (Cercopithecus ascanius schmidti), and small number of de Brazza’s monkey (Cercopithecus neglectus). Several West African forest mammals occur, such as potto (Perodicticus potto), giant otter shrew (Potamogale velox) and Lord Derby's anomalure (Anomalurus derbianus). The small mammal community is also very rich and shows strong affinities to the Congo basin. At least 28 snake species are recorded, including the rare Goldie’s tree cobra (Pseudohaje goldii) and other West African species such as the barred green snake (Philothamnus heterodermus carinatus), black-lined green snake (Hapsidophrys lineata), Jameson's mamba (Dendroaspis jamesoni kaimosae), green bush-viper (Atheris squamiger squamiger), prickly bush-viper (Atheris hispida) and rhinoceros-horned viper (Bitis nasicornis) (Spawls, 1978). Two notable and probably endangered forest amphibians, Leptopelis modestus and Hyperolius lateralis, are recorded (Duff-MacKay, 1980). The forest's butterfly fauna is very diverse and important, both regionally and continentally; around 350 species are thought to occur, including at least one endemic species, Metisella kakamega, and a near-endemic, Euphaedra rex (Larsen, 1991).

Kakamega's avifauna is unique, not only nationally but also continentally. Several species have isolated, relict populations here, including Ansorge's greenbul, blue-headed bee-eater, Chapin's flycatcher and Turner's eremomela, which are absent from all or nearly all of the superficially similar mid-elevation forests in Uganda. Chapin's flycatcher is a restricted-range species which characterizes the Kakamega and Nandi Forests Secondary Area, and is also present in the Albertine Rift Mountains Endemic Bird Area. The presence of the eremomela indicates biogeographic links to the Eastern Zaire Lowlands Endemic Bird Area. Kakamega itself has few endemic taxa; among birds, there is an endemic sub-species (kavirondensis) of Ansorge's greenbul. At least 16 bird species occur in Kakamega but nowhere else in Kenya, and another 30 (such as the grey parrot) are probably now confined to this site. The grassy glades have their own distinctive avifauna, with many moist-grassland species that are now rare elsewhere in western Kenya.

Kakamega has a rich diversity of trees, with common genera including croton, celtis, trema, antiaris, Bequaertiodendron and Zanthoxylum (Beentje, 1990). Endemism is low, however, withthe only woody endemic being the liana Tiliacora kenyensis.

Justification of Outstanding Universal Value

Criterion (vii): The undulating terrain with steep sided river valleys gives the forest its exceptional natural beauty and acts as/and is an important catchment for Isiukhu and Yala Rivers. It is one of Africa's top bird-watching forests.

Criterion (ix): Kakamega forest is one of the most important wintering spots for palearctic bird species. It also host regional migrant species.

Criterion (x): Kakamega forest has a unique presentation of avifauna with 16 species of bird found only in Kenya; it is an important and significant natural habitat for conservation of avifauna as it currently provides a habitat for the highest number of forest-dependent bird species in Kenya.

Statements of authenticity and/or integrity

Kakamega forest was first gazetted as a Trust Forest in 1933. This status was maintained until 1986 when a total of 4,000 ha of the northern portion of the forest, along with the adjacent 457 ha of Kisere Forest, were amalgamated and gazetted as Kakamega National Park.

Conservation issues

Kakamega is a complex and fragmented forest, and one that has been under attack, from inside and out, for many years. However, to reduce the level of poaching for forest products in the forest KWS has developed a participatory forest management approach that incorporates the community in conservation initiatives.

Comparison with other similar properties

Kakamega forest can be compared to Kibale and Mabira forests in Uganda, as they have the same species diversity and are an important bird area. Kakamega forest is, therefore, proposed for serial listing with these similar forests in Uganda since they have similar characteristics in terms of species diversity and signify the end of Congo basin forests.