Visiting Serengeti is where you can see the big migration up close. Large amounts of Wildebeests migrate all through the year, followed by lots of zebras and some Grants gazelles, Thompson gazelles, and Impala. They keep searching for fresh grass and drinking water. Even though their migration cycles are quite predictive, it may change a bit according to when the rainy seasons start, and the amounts of rain.
From February to March they are all gathered in southern Serengeti and north in Ngorongoro Conservation Area. Most of the wildebeest are giving birth in February and may be one of the most amazing happenings in Serengeti. Slowly they start moving west, but in April they head north for fresh feeding grounds. In May you can see large groups moving together.
On their way north, they get delayed by the Grumetti River, so large groups of animals are gathered here, before they find the right way to continue north during July/August.
It is not before September they meet their most dangerous destination, the big and dangerous crossing of the Mara River. This crossing may be a spectacular view, where confusion and panic quickly spread in the crowd while they try to find a safe way to the other side of the river.
In October they will be grassing the southern plains of the Masai Mara National Park in Kenya.
They start coming back to the southern planes of Serengeti already in December, ready for the new cycle to begin.
Even though many animals are migrating, not all of them are. In Serengeti you will always be able to see lots of animals.