Hirola are found in the area between the Tana River in Kenya and the Juba River in Somalia. In 1963 a small population of about 20 individuals were introduced into the Tsavo East National Park from the South Garissa District.
Biogeographic Regions: ethiopian (Introduced , Native )
- Kingdon, J. 1997. The Kingon Field Guide to African Mammals. London and California: Academic Press.
- Nowak, R. 1999. Walker's Mammals of the World Sixth Edition Volume II. Baltimore and London: The Johns Hopkins University Press.