A Blue wildebeest (Connochaetes taurinus taurinus) territorial bull stands alongside a Camelthorn tree in the dry Nossob riverbed of the Kgalagadi Transfrontier Park in Southern Africa. Territorial males aside, the blue wildebeest, or southern brindled gnu, is constantly on the move, searching for water and avoiding predators. Large herds of this antelope, numbering several thousand individuals, inhabit the savanna and plains of southern Africa south of Kenya. They are a major prey animal for large carnivores such as lions and are thus active both during the day and at night.