Serengeti direction through the Serengeti National Park and north towards the Masai Mara reserve in Kenya. This migration is a natural phenomenon determined by the availability of grazing. The initial phase lasts from approximately January to March, when the calving season begins – a time when there is plenty of rain-ripened grass available for the 260,000 zebra that precede 1.7 million wildebeest and the following hundreds of thousands of other plains game, including around 470,000 gazelles. During February, the wildebeest spend their time on the short grass plains of the southeastern part of the ecosystem, grazing and giving birth to approximately
Serengeti National Park to describe the area, "siringet", which means "the place where the land runs on forever". The first American to enter the Serengeti, Stewart Edward White, recorded his explorations in the northern Serengeti in 1913. He returned to the Serengeti in the 1920s and camped in the area around Seronera for three months. During this time, he and his companions shot 50 lions. Because the hunting of lions made them scarce, the British colonial administration made a partial game reserve of in the area in 1921 and a full one in 1929. These actions were the basis for Serengeti National Park,