Sites - Important Bird and Biodiversity Areas (IBAs)
email a friend
Mount Elgon (Kenya)
Kenya, Rift Valley Province,Western Province
34o 37.98' East 1o 0.48' North
A1, A2, A3
2,100 - 4,280m
Year of IBA assessment
Site description This area comprises montane forest, wooded grassland, bamboo and alpine moorland on the eastern slopes of Mount Elgon, Kenya’s second-highest mountain. Mount Elgon lies c.140 km north-east of Lake Victoria and is bisected by the Kenya/Uganda border. It is an ancient, eroded volcano with a huge caldera and, on its summit, the spectacular flat-topped basalt column known as Koitobos. Another unique feature of the mountain is the ‘lava tube’ caves, some over 60 m wide and frequented by elephants (and other animals) digging for salts. The mountain soils are red laterite, and rainfall is c.1,200 mm on the mid-slopes. The vegetation is zoned by altitude, with wet montane forest dominated by Olea capensis and Aningeria adolfi-friedericii grading into Olea–Podocarpus falcatus forest, a zone of mixed Podocarpus and bamboo Arundinaria alpina,and the Hagenia abyssinica zone with giant heath Erica arborea and E. trimera elgonensis. Afro-alpine moorlands occupy the highest parts of the mountain, with tussock grasses such as Festuca pilgeri, bogs of Carex runssoroensis, giant groundsels and giant lobelias.Open wooded grassland with Erythrina and Combretum covers part of the lower, drier north-eastern slopes. Mount Elgon National Park (16,900 ha, gazetted in 1968) covers a narrow transect up the north-eastern slopes of the mountain, from lower montane forest to the caldera edge. The remaining forest and moorland (73,000 ha) is part of Mount Elgon Forest Reserve. The north-eastern wooded grassland (c.5,000 ha) is unprotected. The Ugandan side of the mountain, above c.2,000 m, is protected within Uganda’s Mount Elgon National Park. Mount Elgon is an important water catchment for the Nzoia river, which flows into Lake Victoria, and for the Turkwel river, which flows into Lake Turkana (IBA KE028).
Key Biodiversity See Box and Tables 2 and 3 for key species. The globally threatened, restricted-range Macronyx sharpei is local and uncommon on the moorland (where it has been collected at 3,400 m). Other restricted-range species are Cisticola hunteri, which is common above 3,500 m, and Francolinus jacksoni known from just one sight record. Mount Elgon has a rich montane avifauna. The wooded grasslands on the north-eastern side hold a number of unusual birds, including the Sudan–Guinea Savanna biome species that all have very restricted ranges in Kenya. Nineteen of Kenya’s 43 Guinea–Congo Forests biome species have been recorded, although as many as 10 of these may now be extinct. Regionally threatened species include Gypaetus barbatus, Stephanoaetus coronatus (resident in small numbers), Francolinus streptophorus (very scarce), Sarothrura affinis (scarce resident), Bubo capensis; Glaucidium tephronotum (uncommon), Indicator conirostris (uncommon), Phyllastrephus baumanni (may be extinct), Kakamega poliothorax (may be extinct), Sheppardia polioptera (uncommon) and Campephaga quiscalina (uncommon).
Non-bird biodiversity: Among mammals, the rare Felis aurata has been recorded in this forest, but its status is unknown, and Loxodonta africana (EN) and Tragelaphus eurycerus (LR/nt; declining and uncommon in Kenya) occur. There is a distinctive endemic subspecies of Tragelaphus scriptus heterochrous, and several endemic small mammals, including Crocidura elgonius (VU), Tachyoryctes ruddi and Mus sorella. The frog Anthroleptides dutoiti (EX) is known only from one specimen collected from the Koitobos river on Mount Elgon in 1980. Notable alpine plants include Senecio johnstoni elgonensis, Lobelia deckenii elgonensis, Lobelia cheranganiensis, Alchemilla elgonsis, A. microbetula and Helichrysum amblyphyllum, all of which are endemic or near-endemic to Mount Elgon.