The Kopjes of Serengeti

Serengeti is a vast plain of grassland, woods and swamps, nearly 30,000 square kilometers, that stretches from north-western Tanzania into south-western Kenya. The plains are home to approximately 70 large mammal and some 500 avifauna species, including the largest terrestrial mammal migration in the world. Dotting this vast savannah are outcrops of granite that stick out like rocky islands in a sea of grass. They are called kopjes, and were formed when the soft volcanic rock and ash that covers Serengeti were eroded away to expose the extremely old metamorphic rock below. Standing majestically around plains of savannah with vegetation dominated by bushes and grass these beautiful metamorphic rocks consist of very hard granite capable of resisting erosion from rain and harsh tropical winds. Aside from providing a scenic contrast to the surrounding grasslands, kopjes provide habitat for many creatures because of the presence of a variety of plants, caves for dwelling, water, and a vantage point for Serengeti’s many predators. Simba Kopje. Photo credit Kopjes are essentially piles of ancient rocks that poke through the more recent soils and surface rocks. These rocks were laid down more than 500 million years ago all over Africa. Over this, volcanic activity from volcanoes of the Ngorongoro highlands deposited a layer of rocks and ash, about one million years ago, to create a rich and fertile soil that produces short, sweet grass when it rains. As the surface rock and soil wore away, it exposed the uneven top of the granite layer forming kopjes. Kopjes are refuges for life in the Serengeti. On top of these natural structures some special plants grow by sticking roots into the cracks in the rocks that trap soil and nutrients. There are many animal species that only live on kopjes because of these plants, the rocky habitats and hiding places they offer.