[1] The ecoregion occupies the middle and upper reaches of Kenya's Tana River watershed and the closed basins in the Kenyan portion of the East African Rift including those of lakes Magadi, Naivasha, Nakuru, Baringo and the uplands south and west of Turkana.

To the east and northeast they transition into the drier Somali Acacia–Commiphora bushlands and thickets and Masai xeric grasslands and shrublands.

In Kenya's mountains, the Acacia–Commiphora bushlands transition to humid East African montane forests at higher elevations.

[1] Elephants (Loxodonta africana) are major shapers of the ecoregion, knocking down trees for forage and opening up areas of grassland and savanna.

In addition to elephants, large mammals include the Eastern Black Rhinoceros (Diceros bicornis michaeli), Grevy’s Zebra (Equus grevyi), Beisa Oryx (Oryx beisa), Gerenuk (Litocranius walleri) and Lesser Kudu (Tragelaphus imberbis).