July – September
By July, the herds have split up a bit, some heading up through the central Serengeti, and the rest father west in the Grumeti Reserve. By August and September, they have congregated along the most imposing obstacle on the entire migrator corridor: the mighty Mara River. This steep-banked river separates hungry herds from lush grazing in the Maasai-Mara Reserve of Kenya. The deep flowing water creates a challenging obstacle and confusion reigns as these herds try to find a way across. This is a prime opportunity for predators like crocodiles, unhappy hippos, and vultures waiting to clean up the aftermath. Crossings are chaotic and panic-driven and are truly one of the most dramatic spectacles on the continent. Thousands of frantic wildebeest leaping and falling off the riverbanks, rushing through the waters, swimming for their lives, getting confused, turning around and then turning around again! There’s no telling when these crossings happen so you’ll need a little luck and patience in order to catch this. This is also peak season, so its unlikely to have a crossing all to yourself – you’ll need a pro-guide who knows both where to go and how to get you in the best spot to witness the event.
October – January
As all of the green grass is devoured by the hungry herds, and what remains begins to dry out from lack of rain, the herds begin to head back south toward the Serengeti, again crossing the Mara River. The short rains begin in late October and early November, As the grass grows, the zebra and wildebeest work symbiotically – zebras eating the long grass which exposes the short grass preferred by the wildebeests. It’s not too late to still visit – one of the most amazing river crossings we ever saw was at the end of October! Through December and into January the migration continues to push south and congregate on the edge of the Ngorongoro Conservation Area on the southern edge of the Serengeti in time for the February calving season and the beginning of the entire cycle again.