This area is an isolated basalt mountain with dramatic cliff faces that tower above the surrounding plain, Ol Donyo Sabache is some 30 km north-west of Archer’s Post along the main Isiolo–Marsabit road. It is often called Ololokwe, a name that refers to the general area rather than the mountain itself. Three-quarters of its circumference (c.14 km) is a sheer precipice up to 500 m high. The summit is a plateau of c.900 ha, divided in two by a small wooded valley that contains several springs. Around half the summit area is covered by dry Juniperus–Podocarpus forest, with numerous cycads Encephalartos tegulaneus. The steep cliffs are sparsely vegetated. The semi-arid plains below (at 1,100 m) are covered by bushland, but with many drainage lines that support some taller trees.
See Box for key species. Ol Donyo Sabache is one of the most important sites in Kenya for birds of prey. At least one pair of Falco fasciinucha nests here, and 61 other diurnal raptors and nine species of owl have been recorded on the mountain and its foothills. The mountain is a stop-over and ‘refuelling’ point for numerous Palearctic migrants, including unusual species such as Accipiter brevipes, Accipiter nisus, Falco cherrug and Falco peregrinus (race calidus), as well as Falco amurensis, Buteo buteo and Pernis apivorus. Raptors nesting on the mountain (in forest or on the cliffs) or in the drainage lines below it include Aquila verreauxii, Hieraaetus spilogaster and the regionally threatened Hieraaetus ayresii, Plomaetus bellicosus and Aquila rapax, Polyboroides typus, Terathopius ecaudatus, Falco peregrinus and (probably) Falco pelegrinoides, and Bubo capensis. Stephanoaetus coronatus nested here until the drought year of 1984. Up to 120 Gyps rueppellii roost and nest in a colony on the cliffs. The avifauna at the base of the mountain is similar to that in Samburu National Reserve (IBA KE033), while that on the summit contains an impoverished set of species characteristic of the central Kenyan highlands, including the restricted-range Cisticola hunteri. Regionally threatened species include Gypaetus barbatus (rare visitor), Polemaetus bellicosus (nests near the base of the hill) and Stephanoaetus coronatus (not recorded since 1984).
Non-bird biodiversity: The large mammal Diceros bicornis (CR) formerly occurred here, but the animals were translocated to sanctuaries in 1982. Loxodonta africana (EN) move on to the mountain from the plains during the wet season, and six individuals of Lycaon pictus (EN) were sighted here in 1995. Ol Donyo Sabache shelters a near-endemic plant, Streptocarpus exsertus, and many fine specimens of the rare cycad Encephalartos tegulaneus.
Pressure/threats to key biodiversity
The forest on Ol Donyo Sabache has been deteriorating since the drought of 1984. Populations of livestock (mainly cattle and goats) had built up on the plains, thanks to the provision of new watering points. When drought struck, the only available grazing was on top of the mountain. The hillsides and summit were set on fire, in the belief that this would encourage rain, kill ticks and improve grazing. The effect was to destroy many forest trees and cause the springs to dry up, in turn causing the death of much wildlife and livestock as well. Subsequent fires, and continued grazing pressure, have severely damaged the forest and other vegetation on the summit. The cycads are fire-resistant, but many have been damaged by Samburu moran who cut the leaves away in order to collect and eat the cones. Other threats are less serious. Visitors to the site, mainly climbers, leave a considerable amount of garbage on the climbing route and at campsites. The main cliff face has at times been extensively mortared and shelled for military practice, thus disrupting nesting raptors. With its magnificent views, extraordinary diversity of raptors and proximity to the Shaba, Samburu and Buffalo Springs National Reserves (IBAs KE033 and KE034) Sabache has potential for ecotourism. A community-based programme might be developed to protect the mountain and its vegetation, while bringing in revenue to compensate for the potential loss of dry-season grazing.