December – March (Ngorongoro Conservation Area & Southern Serengeti)Highlight: calving season
Vast herds of wildebeest spend the short rain season in the open volcanic plains below the Ngorongoro Crater and in the southern part of the Serengeti where the grass growth is most productive and nutritional. This area is the starting point for one of the great wonders of the world: the Serengeti Annual Migration. Wildebeest have synchronized birthing, which means that about 90% of calves are born within three weeks.
April – May (Central Serengeti & Western Serengeti)
Highlight: Seeing the herds on the plains
As the grass gets depleted in the Southern Serengeti, herds move to the plains and woodlands of the Central Serengeti. The mortality rate is quite high due to injuries and fatigue, motivating large numbers of griffon vultures to follow the herds on their journey. The zebras join the migration as well as a scattering of Thompson's and Grant's gazelles.
June (Western Serengeti)
Highlight: Scenes of the Grumeti River
The Grumeti River is northwest of the short grass plains. This watercourse is their first real obstacle, and gigantic Nile crocodiles (up to 6 metres in length) are waiting for the hesitant wildebeest to stumble at the crossing. Their livelihood is inextricably linked with the great migration. After moving westwards, the migration divides by some uncanny instinct, one group turning northeast and the other due north.
July - August - September - October (Northern Serengeti and Masai Mara)
Highlight: River crossings
Following the rainfalls, the migrating animals move north and will stay in the Masai Mara National Reserve and the Northern Serengeti. Nothing stops the stampeding hordes. Tempted by greener pastures, the wildebeest arrive at the Mara River around July and cross over onto the Masai Mara plains. During these four months, many animals cross and re-cross the Mara River several times following periodic rain showers. Crossing points form bottlenecks in which thousands of animals perish through trampling or drowning. Not surprisingly, hyenas, lions, leopards, crocodiles and even cheetahs capitalize on this glut of fresh meat. Typically, the wildebeest remain in the Masai Mara until October when they start returning to the Southern Serengeti.
November (Southern Serengeti)
Highlight: Seeing the herds on the Serengeti plains
The army of animals returns southward to the replenished grasslands of the southern Serengeti, thereby completing the migratory cycle.