The wildebeest migration is one of the most spectacular natural events in the world, involving the movement of massive herds of wildebeests (and other herbivores) across the grasslands of East Africa. The migration primarily takes place in the Serengeti ecosystem of Tanzania and the Maasai Mara in Kenya. The migration is a complex and cyclical process that revolves around the search for food, water, and suitable breeding grounds. Here's how the wildebeest migration works:

Rainy Season and Births:

The migration begins with the rainy season. In the Serengeti, this is usually around November, and in the Maasai Mara, it's around April.

The rains stimulate new growth of grass, which provides abundant food for the wildebeests and other grazers.

During this time, wildebeest herds gather in the southern Serengeti or the Ngorongoro Conservation Area to give birth to their calves. The timing of the births coincides with the availability of fresh grass for the young calves to feed on.

Food Depletion:

As the rainy season progresses, the herds graze on the lush grasses in the southern areas, but eventually, the food supply starts to diminish.

Instinctual Trigger:

Instinctively, the wildebeests sense the decreasing food supply and begin to feel the urge to move in search of greener pastures and water sources.

Migration North:

Around May to June, the wildebeest herds start their journey northward, following the rains and the growth of new grasses.

The migration is driven by a quest for food, as well as the need to find water, especially in the dry season.

River Crossings:

One of the most dramatic aspects of the migration is the river crossings, particularly at the Mara River in Kenya. As the herds move north, they encounter rivers that must be crossed to reach better grazing areas.

River crossings can be treacherous, as they expose the wildebeests to predators like crocodiles and lions. Many wildebeests perish during these crossings.

Looping Movement:

The migration follows a somewhat circular or looping movement, where the herds move northward into the Maasai Mara and then, as the dry season approaches, begin their journey back to the south.

This cyclical movement ensures that the wildebeests have access to food and water throughout the year.

Return South:

As the dry season progresses and the grasses in the northern areas are depleted, the wildebeest herds start their journey back to the southern Serengeti and Ngorongoro Conservation Area.

Calving Season Again:

By November, the wildebeests return to the southern areas where they began their journey. The cycle starts anew with the calving season.

The wildebeest migration is a remarkable example of nature's balance and adaptation. It's driven by the availability of resources, instinctual behaviors, and the constant cycle of life and survival. The migration not only involves wildebeests but also other herbivores like zebras and antelopes, as well as predators like lions and hyenas that follow the herds for their own sustenance.