Arabuko-Sokoke Forest This is an IBA in Danger! 

Country/territory: Kenya

IBA criteria met: A1, A2, A3 (1999)
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Area: 41,600 ha

IBA conservation status
Year of assessment (most recent) State (condition) Pressure (threat) Response (action)
2022 unfavourable very high high
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Site description (2001 baseline)
Arabuko-Sokoke lies a few kilometres inland on the Kenyan coast, between the towns of Kilifi and Malindi and some 110 km north of Mombasa. It is the largest extant fragment of the forests that once covered much of the East African coast, and whose remnants constitute the East African coastal forests Endemic Bird Area. Arabuko-Sokoke was proclaimed a Crown Forest in 1932 and gazetted in 1943, covering an area of 39,100 ha. The Kararacha extension (2,700 ha) to the south-east, which includes important tracts of key habitats, was added in 1968. Part of the forest, containing sections of the three main habitat types, was gazetted as a strict nature reserve (covering 4,300 ha) in the late 1960s. Average annual rainfall ranges from 900 mm (in the relatively dry and scrubby north-west) to 1,100 mm (in the east). The relatively flat eastern section lies on Pleistocene lagoonal sands and clays, separated by a wide band of apparently riverine sandy deposits from the ridge of red Magarini sands that forms the western part of the reserve. Three very distinctive forest types, each with its own special flora and fauna, correspond to these soil types:

Mixed forest (7,000 ha) in the east, on grey sands. This habitat is relatively dense, tall and undifferentiated, with a diversity of tree species. Characteristic trees include Combretum schumannii, Drypetes reticulata, Afzelia quanzensis, Dialium orientale, Hymenaea verrucosa and Manilkara sansibarensis. Brachystegia woodland (7,700 ha) runs in a strip through the approximate centre of the forest, on white, very infertile soil. This relatively open habitat is dominated by Brachystegia spiciformis. In the west, on red Magarini sands, is Cynometra forest and thicket, dominated by Cynometra webberi with Manilkara sulcata, Oldfieldia somalensis and (formerly) Brachylaena huillensis. The transition between white and red soil is sudden, and marked by a chain of seasonal ponds. There are two areas of relatively tall Cynometra forest, with a canopy height of up to 20 m, in the north (3,300 ha) and the south (6,600 ha) of this zone. Between these is a lower, scrubbier formation of intermediate Cynometra (11,300 ha) with a canopy height of 7–8 m. The dry north-western part of the reserve is covered by a low, dense, and often almost impenetrable Cynometra thicket (2,300 ha), with the canopy no more than 5 m high. Altogether, the area of indigenous forest or thicket at this site totals c.38,200 ha.

Key biodiversity
See Box and Tables 2 and 3 for key species. Arabuko-Sokoke has been ranked by BirdLife International as the second most important forest for bird conservation on mainland Africa. More than 230 bird species are recorded including nine globally threatened species. Ploceus golandi is known only from Arabuko-Sokoke and the little-studied Dakatcha woodland (IBA KE009). It occurs mainly in Brachystegia woodland, although its numbers fluctuate. The species’ nest is unknown. Otus ireneae is known only from this forest and one other site in north-east Tanzania. It is confined to Cynometra forest and (at much lower densities) intermediate Cynometra. Arabuko-Sokoke holds by far the bulk of the world’s population, with an estimated 850–1,200 pairs. Arabuko-Sokoke may also hold the world’s largest population of Sheppardia gunningi, with as many as 9,000 pairs thought to be present, primarily in the Cynometra forest. It is also a world stronghold for Anthus sokokensis, with around 3,000 individuals estimated to occur in the Brachystegia woodland alone; its status in other habitat types is not well-known. Zoothera guttata is a scarce but regular intra-African migrant from March–October, and Anthreptes pallidigaster is very local, occurring principally in the Brachystegia woodland, with an estimated population of 2,800 birds. Regionally threatened species include: Casmerodius albus, Thalassornis leuconotus and Podica senegalensis (all recorded occasionally on forest pools); Hieraaetus ayresii (a scarce resident); Stephanoaetus coronatus; Pitta angolensis (a scarce non-breeding visitor, with few recent records); Turdoides squamulatus (local and rarely recorded); and Erythrocercus holochlorus.

Non-bird biodiversity: Arabuko-Sokoke is rich in rare and endemic wildlife, especially among the fauna. Six taxa of butterfly endemic to the EastAfrican coast are present, as well as three rare, near-endemic mammals: Rhynchocyon chrysopygus (EN), Cephalophus adersi (EN; found only in Sokoke and Zanzibar) and the distinctive small carnivore Bdeogale crassicauda omnivora. There is also a small population of Loxodonta africana (EN), and Felis aurata, rare in Kenya, may occur. Unusual reptiles include the lizard Gastropholis prasina, and the forest is exceptionally rich in amphibians, including coastal endemics such as Mertensophryne micrannotis. Arabuko-Sokoke supports at least 50 globally or nationally rare plant taxa.

Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Arabuko-Sokoke Forest. Downloaded from on 26/02/2024.