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Kobus vardonii (Livingstone, 1857) is a bovid commonly known as the puku. It is a medium-sized antelope with a golden-yellow coat and white underparts, sexually dimorphic as only males carry lyre-shaped horns, and according to current taxonomy it is one of 12 extant species in the genus Kobus. Adult males defend territories, whereas females and young move around in unstable groups. Feeding on a great variety of grasses, K. vardonii occurs in grasslands along rivers and lakes in southern central Africa with Zambia being the center of its distribution and Tanzania holding the largest population. It is classified as “Near Threatened” on the IUCN Red List of Threatened Species.

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.

Diet and dietary competition among puku (Kobus vardonii) and other grazing bovids were investigated in Kasanka National Park, Zambia, a prime area for puku. The objective was to provide new insights into the puku’s feeding ecology including autecological and synecological traits. Other bovids assessed for their diets were sitatunga (Tragelaphus spekii), reedbuck (Redunca arundinum), Lichtenstein’s hartebeest (Alcelaphus lichtensteinii), sable antelope (Hippotragus niger) and African buffalo (Syncerus caffer). Dung was collected during different periods in 2009 and 2010 and examined using microhistological analyses. The diets were assessed for potential differences or overlap using the Pianka Index. Puku feed mainly on monocotyledons and consumed Panicum spp., Brachiaria sp., Sporobolus spp. and Hyparrhenia/Andropogon grasses. Differences in dietary composition between sexes were observed, especially during the cool dry season, as well as differences at a temporal and spatial scale. It can be concluded that puku exhibit a flexible diet with regard to grass species. Diet breadth changed throughout the year being narrowest in the late rainy season but showed no sexual differences. The dietary overlap of puku with other grazing bovids was low. This combination contributes to the puku’s extraordinary situation in Kasanka National Park.

Differences in resource selection (i.e., habitat selection and diet composition) may allow for coexistence of interspecific competitors. Two congeneric floodplain antelope with broadly similar habitat use are puku (Kobus vardonii) and lechwe (K. leche). In Botswana, puku are restricted to a narrow band of floodplains along the Chobe River, whereas lechwe are far more abundant, with a distribution encompassing the Chobe Riverfront, the Linyanti Swamps, Kwando River, and the Okavango Delta. We investigated factors to try to explain the contrasting distribution patterns of puku and lechwe, including seasonal diet composition and overlap, seasonal nutritional status as indicated by fecal nitrogen and phosphorus, and habitat selection. Dietary overlap ranged from 84% to 90% across seasons. Cynodon dactylon was the greatest contributor to the diets of both puku and lechwe, but there were differences in the relative contributions of particular grass species associated with uplands or floodplains. Fecal ...