Essay: Africa

Africa is the earth’s second largest continent, contributing to nearly 20% of the total land area, (Cooke, 1978). Africa has various topographical variations and landscapes which differ from region to region. These differences in topographical units influence precipitation and habitat heterogeneity to a large extent as do the various geological formations and parent base material of which the soils consist. These factors have contributed to a large variety of adaptations in mammalian fauna and resultant diet and habitat preferences, (Talbot 1965; Keya 1973; Maglio and Cooke 1978).
Wildlife increasingly occurs in reserves of various sizes with great habitat variation and ability to sustain these populations endlessly without active management being brought in to question (Soule, Wilcox and Holtby 1979).
Early pioneers like Lamprey (1964) found in Tarangire Game Reserve in Tanzania that certain animals like wildebeest (Connochaetes taurinus), zebra (Equus burchelli) and buffalo (Syncerus caffer) fed exclusively on grass whereas animals like giraffe (Giraffa camelopardalis) and dik-dik (Madoqua kirkii) fed almost exclusively on browse. Ungulates like eland (Tragelaphus oryx) and impala (Aepyceros melampus) are mixed feeders taking both browse and graze in varying proportions during different seasons. These observations were not subject to statistical analysis but the fact remains that certain ungulates utilize certain vegetation in their diets during different seasons as well as different habitats.
The proportions of different plant parts found in faecal samples indicates trophic distinctions between grazing species, zebra diets showed prevalence toward stem material and wildebeest diets showed prevalence toward leaf material, on the other hand, Thompson’s gazelle (Gazella thomsonii), showed a large proportion of fruit in their diet. Clearly, grass is not utilized in the same manner by all grazing ungulates. The nutritional content of the grass structures differ from one another as well as with the change in seasons (Jarman and Sinclair 1979). Therefore, migratory ungulates utilize rainfall patterns in their movement from one area to the next to gain maximum nutrients from the protein rich green grass swards (McNaughton 1976; McNaughton 1985). This leads to the logical conclusion that ungulates utilize different plant structures and different plant species depending on the changes in nutrient content over the seasons (Vesey-Fitzgerald 1960).