Population characteristics and coexistence of puku (Kobus vardonii) and impala (Aepyceros melampus) in and around Kafue National Park, Zambia

Sympatric occurrence of puku (Kobus vardonii) and impala (Aepyceros melampus) characterises large parts of the protected areas in Zambia. The present study assessed traits of the populations as well as spatial and dietary overlap of both antelopes in Kafue National Park and adjacent Game Management Areas in western Zambia. Data were collected via distance sampling along line transects (population and distribution) and via microhistological analyses of dung (diet). Hunting activities might result in fewer males in both antelopes in the Game-Management areas. During the cool dry season there was considerable spatial overlap between puku and impala. However, puku are more abundant in grassland areas, while impala reach highest population densities in intermediate habitats. The diet of puku was characterised by high amounts of grasses during both the cool dry season and the late rainy season. Impala shifted from browsing during the cool dry season to a more grazing diet during the rainy season. This study found niche partitioning via habitat and diet as a key to understand the coexistence of these antelopes and improves our knowledge of Zambian Wildlife.