Country/territory: Angola

IBA criteria met: A1, A2, A3 (2001)
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Area: 40,000 ha

Site description (2001 baseline)
The site lies north and north-east of the town of Buco-Zau, in the Maiombe forest on the watershed of the Chiloango and Loémé rivers (Congo). No specific climatic data are available for the site, but it lies within the 1,200 mm isohyet. The moist forests in the area have a rich and robust flora, with a very high canopy (c.50 m) and poor undergrowth with very few grasses. Dominant trees are Gilletiodendron, Librevillea, Tetraberlinia and Julbernardia. There is an abundance of flowers and fruit throughout the year and frugivorous mammals and birds are common. The undergrowth has been replaced with coffee in the southern parts of the region, but current coffee production is likely to be low, and the forests are probably relatively undisturbed by people.

Key biodiversity
See Box and Table 3 for key species. The site has the highest number of species in Angola that are restricted to the Guinea–Congo Forests biome but, apart from 301 specimens collected in the general area during the late 1800s (Sharpe and Bouvier 1876a, 1876b, 1877, 1878) and during the late 1960s by the IICA (Pinto 1972), the avifauna is virtually unstudied. Despite this, the bird fauna is clearly species-rich, and significantly more species probably await discovery. Three species characteristic of the Zambezian biome, and one of the Afrotropical Highlands biome, also occur.

None of the Angolan endemic bird species have as yet been recorded from the area. Rare species that are likely to occur include Accipiter castanilius, Urotriorchis macrourus, Himantornis haematopus (recorded widely in dry-land rainforest in the adjacent Mayombe region in Congo by Dowsett-Lemaire et al. 1993), Bubo poensis, Bubo leucostictus, Scotopelia bouvieri, Caprimulgus nigroscapularis, Rhaphidura sabini, Neafrapus cassini, Tockus hartlaubi, Ceratogymna cylindricus, Nectarinia johannae and Anthreptes gabonicus. Ploceus subpersonatus (a globally threatened species) and Ploceus aurantius probably occur in lowland swamps along the rivers.

The Maiombe is one of the few collecting localities in Angola for Accipiter tachiro toussenelii and Anthreptes fraseri, and several of the lesser-known forest bulbuls (Calyptocichla serina, Ixonotus guttatus, Phyllastrephus icterinus, Criniger calurus, C. chloronotus and C. ndussumensis) and barbets (Gymnobucco peli and Buccanodon duchaillui) are known from the general area (Pinto 1972). Other poorly known species that have been collected in the region include Hieraaetus ayresii, Agelastes niger, Poicephalus gulielmi, Agapornis pullaria, Centropus monachus, Nectarinia bouvieri, Ploceus pelzelni, Pyrenestes ostrinus and Clytospiza monteiri.

Non-bird biodiversity: The forest generally lacks grazing antelope, but browsers such as Hyemoschus aquaticus (DD), Cephalophus sylvicultor (LR/nt), C. nigrifrons (LR/nt) and C. dorsalis (LR/nt) occur. The primates include Gorilla gorilla (EN) and Pan troglodytes (EN).

Recommended citation
BirdLife International (2023) Important Bird Area factsheet: Maiombe. Downloaded from on 05/10/2023.