Tsavo West National Park is a vast expanse of savanna stretching from the Athi river, north of the Mombasa–Nairobi road, south to the Tanzanian border. The north-east boundary along the Athi adjoins Tsavo East National Park (IBA KE024), but Tsavo West has a more varied topography and a more diverse array of habitats than its neighbour. Most of the northern sector is Acacia–Commiphora bushland, with scattered trees such as baobabs Adansonia digitata and Delonix elata. There are numerous rocky outcrops and ridges, and, towards the Chyulu Hills, ash cones and lava flows—some of them very recent. In the Ngulia area, a range of craggy hills reaches c.1,800 m and is heavily wooded. The southern sector consists of open grassy plains. The permanent Tsavo river runs through the northern part of the park, with a fringe of riverine Acacia elatior and Hyphaene compressa woodland. In the far south-west corner on the Kenya–Tanzania border is Lake Jipe, part of which is in the park. Run-off from Mount Kilimanjaro and the North Pare mountains feed this very attractive lake. It is bordered by extensive beds of Typha and has large permanent swamps at its eastern and western ends. At Mzima Springs, in the north of the park, water that has filtered underground from the Chyulu Hills gushes into a series of clear pools, rich in fishes and fringed by Raphia farinifera and Phoenixreclinata palms. Tsavo West houses one of Africa’s premier bird ringing stations, Ngulia Safari Lodge, which is located on the edge of a dramatic escarpment at the foot of Mount Ngulia.
See Box and Table 3 for key species. Tsavo West has a rich avifauna. The enigmatic, Near Threatened Mirafra pulpa has been recorded singing and displaying in years of good rains, and presumably nests here. Tsavo West forms part of a corridor of natural habitat in eastern Kenya through which vast numbers of Palearctic birds migrate, especially in November/December. These include the globally threatened Crex crex (regularly caught at Ngulia Lodge) and Near Threatened Acrocephalus griseldis (regularly ringed at Ngulia; a number of birds may overwinter). Local weather conditions at Ngulia Safari Lodge are often such that thousands of migrating birds are attracted to the lodge’s lights at night, and around 220,000 individuals have been ringed here since 1969. Lake Jipe supports an important heronry, where the regionally threatened Anhinga rufa nests (in small numbers), among other species; this is situated a few kilometres outside the park. Other regionally threatened species include Struthio camelus (common); Casmerodius albus (small numbers at Lake Jipe and Mzima Springs); Trigonoceps occipitalis (resident in small numbers); Polemaetus bellicosus (resident in small numbers); Coturnix adansonii (uncommon); Podica senegalensis (uncommon on Tsavo river); Phoeniculus granti (local and uncommon); and Buphagus africanus (fairly common in extreme south).
Non-bird biodiversity: Tsavo West is well known for its populations of large savanna mammals, particularly Loxodonta africana (EN). The Ngulia Rhino Sanctuary holds a number of Diceros bicornis (CR), and other threatened mammals include Acinonyx jubatus (VU). The frog Afrixalus pygmaeus septentrionalis is known only from the area between Mtito Andei and Voi, but is not considered under threat.
Pressure/threats to key biodiversity
The park faces no major threats at present. The remarkable phenomenon of night-time bird migration over Ngulia Safari Lodge is an ecotourist attraction that is presently little appreciated. This long-term ringing programme has enormous scientific value, and its importance should be better recognized by the park administration.
BirdLife International (2020) Important Bird Areas factsheet: Tsavo West National Park. Downloaded from
http://www.birdlife.org on 26/02/2020.