A Guide to The Annual Wildebeest Migration
Every year the movement of an estimated 1.5 million wildebeest, 500,000 zebra, 200,000 Thompson’s gazelle and 18000 eland across the Serengeti National Park in Tanzania and Masai Mara in Kenya. The migration is a phenomenon that offers action packed game viewing and stunning photographic opportunities. Wildebeest are famous for their annual long-distance migration, seemingly timed to coincide with grass growth after the annual pattern of rainfall. The timing of their migrations in both the rainy and dry seasons can vary considerably (by months) from year to year. The following should be used as a guideline when planning your safari to Tanzania as movement of wildlife depends on a great many aspects but this helps to explain the seasonality of game viewing. The famous Mara river crossings are the highlight moment in the annual event of the great migration.
CALVING: January – March
The big herds of wildebeest are generally in the Southern Plains of the Serengeti ecosystem, calving takes place over approximately two weeks. Lots of predators, good visibility of game, mix of open plains and some woodland.
The life-giving rains that generally begin in mid-November and last through early May trigger the great wildebeest migration into the plains of the South Serengeti and the northern Ngorongoro Conservation Area.
The calving season usually begins towards the end of January. Members of the vast wildebeest herd give birth more or less simultaneously. This is usually over a period of three weeks sometime between January and March when optimum grazing is available on the short grass plains. The peak of calving usually takes place during the first two weeks in February. The exact timing is heavily dependent upon rainfall.
It is also very likely that you could witness an actual birth. Unlike most antelope, wildebeest do not encourage them to get on their feet and join the herds where there is safety in numbers.
THE RUT: April – May
The herds start moving towards central Serengeti. This is typically the rainy season, however, game viewing is still excellent and there are some great discounts available at the lodges and camps. It generally doesn’t rain all day. Photography is normally superb with moody skies and good depth of colour.
The wildebeest migration isn't all about river crossings. Due to their migratory ways, the wildebeest do not form permanent pair bonds.
The wildebeest mating season, rut, is when the males establish temporary territories and try to attract females. The males defend these small territories from other males while trying to attract females that are ready to mate. The males entice females into their territories with grunts and distinctive antics.
Wildebeest usually breed at the end of the rainy season when the animals are most fit. The mating season usually occurs between May and July and birthing usually takes place between January and March, at the start of the wet season. The gestation period is about 8-9 months.
CROSSING THE GRUMETI RIVER: June – August
The wildebeest move from the central area and split to the West and North, continuing their trek toward Mara River. River crossing may be seen in both the Western Corridor (Grumeti Area) and the North (Mara River) within the Serengeti.
By July the wildebeest and their entourage begin the journey from the Serengeti plains towards the green pastures of the Masai Mara. As the plains of the south and east dry out, there is a movement to the north and west, where there is more grass and more dependable water. In a dry year, the first wildebeest could be near the Mara River in early July; in a wet year mid-August. If conditions are very good, and there is plenty of grass and water, the herds spread out all the way from Seronera to the Mara River.
The northward wildebeest migration is divided between two main population groups with different migration routes. The main group follows the Mbalageti and Seronera Rivers from the southern plains into the western corridor, crossing the Grumeti River.
The second main group heads directly north from the plains through the Central Serengeti and directly into the Northern Serengeti and Masai Mara without entering the Western Serengeti.
ENCOUNTERING THE MARA RIVER: September – October
Whilst some of the wildebeest successfully reach the Masai Mara, there are still hundreds of thousands remaining in the northern region of Serengeti, offering those with patience the chance to see river crossings (the Mara River runs through the Serengeti).
In the Masai Mara, the grassy landscape and nutrient wealth for the great herds are created by abundant rains. Up to one and a half million animals pour in from the dry plains of Tanzania. Being in the reserve between August and September when the wildebeest have arrived is a mind-blowing experience. The variety of species is also unique. In one place you may be able to see ten or more species at a time – wildebeest, zebra, giraffe, buffalo, elephant, hyena, lions, eland and gazelle. And if you are lucky enough to witness a river crossing, you are sure to develop a new understanding and respect for the struggle for survival in the African wild.
November – December
The big herds remain on the productive Mara grasslands until November. And then as the storm clouds gather in the south, the vast herds return to their breeding grounds which, by the time they arrive, are once again green and lush. In November to December the big herds start to return from the North, to the Southern plains, to start the whole process all over again!