The numbers and distribution patterns of large mammals in the Ruaha-Rungwa area of southern Tanzania.

Abstract

1. An aerial census of Ruaha National Park, Rungwa and Kizigo Game Reserves, and part of the proposed Mloa-Ilambi Game Controlled Area is described.
2. Zebra, eland, sable, and hartebeest were virtually restricted to the miombo woodlands. Impala and kudu were most common in the rift valley sector of the census zone. Elephants, buffalo, and giraffe occurred throughout the entire area.
3. The 31,500 km² census zone carried one of the largest elephant populations in Africa, an estimated 43,685 ± 9,254 elephants, of which 24,625 ± 7,132 were estimated to occur within Ruaha National Park (10,200 km² in area). The densities of elephants and the combined densities of the other large herbivores were highest in the National Park and lowest in the Game Controlled Area.
4. Within the National Park, comparisons with earlier counts showed an apparent increase in elephant density of 8-10% per annum since 1965. Of the large herbivores, elephants alone showed a significant increase since the 1972 census and only elephant distribution was significantly affected by the distribution of human settlement and hunting. The increase in elephant numbers within the National Park is probably the result of the change in human distribution in the region and a period of higher rainfall.