The African Savanna biome is a tropical grassland in Africa between latitude 15° North and 30 degrees S and longitude 15 degrees W and 40° West. It covers Guinea, Sierra Leone, Liberia, Cote D'ivore, Ghana, Togo, Benin, Nigeria, Cameroon, Central African Republic, Chad, Sudan, Ethiopia, Somalia, and the Democratic Republic of the Congo, Angola, Uganda, Rwanda, Burundi, Kenya, Tanzania, Malawi, Zambia, Zimbabwe, Mozambique, Botswana, and South Africa.
Annual rainfall in the African Savanna is about the same as that of Wisconsin. During the rainy season, beginning in May and ending in November, they get fifteen to twenty-five inches of rain a month. In the dry season they only get about four inches of rain. The dry season occurs more then seven months of the year, from October to March in the southern hemisphere and April to September in the northern hemisphere. The dry season comes in the low sun period and the wet season comes in the high sun period. They have a wet-dry tropical climate.
A rolling grassland dotted with trees is one way to define the African Savanna. The African Savanna is a thornbush savanna, which has many different kinds of plants such as acacia Senegal, candelabra tree, jackalberry tree, umbrella thorn acacia, whistling thorn, Bermuda grass, baobabs, and elephant grass. The Serengeti Plains are a grass savanna that has very dry but nutrient-rich volcanic sand. Around 2 million large plant-eating mammals live in the savanna. There are 45 species of mammals, almost 500 species of birds, and 55 species of acacia in the Serengeti Plains. There are animals such as lions, African wildcats, klipspringer, steenbok, Burchell's zebra, African Savanna monitor, and puff adders. They have the largest diversity of hoofed animals in the world including antelopes, wildebeest, buffalos, zebras, and rhinoceros.
Both plants and animals have adapted very well to living where they live. Some animals are grazers, some are browsers, and some do a little of both. One herd of browsers nibbles at the trunk of a tree, another looks a little higher for food, a third eats even higher than the ones below them, and another herd browses at the very top. Many plants have developed long taproots to reach down to water. Some kinds of trees have thick fire resistant bark and trunks that can store water. Some animals migrate when it gets too hot or too cold for them, and others burrow in the ground. Some animals have tough cheek teeth so they can stand their diets, many animals cannot eat tough grasses like the animals of the African Savanna. Some animals have developed speed for hunting such as cheetahs others such as giraffes have developed long legs to become too high for a cheetah or other predators to get to. Naked mole rats feed on large underground tubers produced by plants, the secretary bird feeds on snakes so it has evolved to have long legs to walk through the grasses, and ostriches can run as fast as 31 miles per hour to escape predators. They can also have very thick skin to make it so predators cannot bite through their skin.
This biome has been helped, hurt, and changed by humans in many ways. For example people use the land for cattle grazing, which kills the grass and turns the savanna into a desert, they cause many fires that destroy the land, use of wood for fuel also causes problems to the environment, and people also poach (hunt the animals illegally) very often causing animals to become extinct. To repair damage people are creating controlled burning programs to keep worse fires from developing, they are creating nature preserves to keep the savanna natural, and they set up a biosphere reserve in South Africa to help protect the environment. The Serengeti and the Ngorongoro Conservation Area together have been named a World Heritage site. The Serengeti is one of the most famous national parks in the world. It has the most grazing animals and their predators in Africa. Some of the greatest wildlife scenes ever seen take place there. The African Savanna takes up almost half of the continent, about 5 million square miles. If it weren't for the efforts that people made to preserve the savanna they may not have all the animals, plants, and other wonderful things they have now.
by Maya S. 2003
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Photo credit: http://mercury.bio.uaf.edu/courses/biol105/Lectures/Section1/photos/50-25bx-Savanna.jpg