The tourist season in the Serengeti fluctuates with the wildlife, and in turn, the wildlife fluctuates with the seasons.
December and January happen to be busy months because that is when many people take their holiday vacation time. Luckily, the end-of-year holidays just so happen to coincide with the return of the green landscapes, following the short rainy season in November. Come in October and the first part of November and the landscape is a dreary thing indeed, the heavy rains from April having all but receded back into the ground. The animals are still there, true, but it becomes a bit harder to spot the large groups, as each herd splits up and heads to where the last of the drinking pools and grazing areas are.
The reason why February is such a big draw isn’t because of the holidays, but because it is the season when hundreds of thousands of wildebeest give birth en masse across the Serengeti. Truly a sight to behold, the giant herds move ever more south towards the rich grazing areas of the “endless plains” in preparation for their due date.
In turn, the traditional predators of wildebeest–hyenas, lions, and even cheetahs–follow the herds in order to have the best chance of scoring an easy meal. This allows one to see all of the action within a relatively small radius, therefore allowing for more wildlife viewing with less overall driving time.
It is undoubtedly one of the very best times of the year to visit the Serengeti.
To maximize your time in the Serengeti be sure to request one of the tented camps around the Ndutu or Salei areas, that way you barely have to leave your tent before you start seeing the animals (and indeed, sometimes you don’t have to move at all, as they come right up to the camping areas). It is best to be quick though–these areas are in high demand, and they fill up very quickly (usually months in advance.)
The birthing season comes to an end around the middle of March as the grasses start to dry up and the herd must move on to graze and look after the newborns somewhere else. Soon after, the annual big rains will quench the land of its thirst, and all will be vibrant again come May.
Note: please keep in mind that nothing is ever 100% when it comes to nature. The mass migration is totally dependent on the wildebeest, and they are dependent on the food sources as well as the rains that feed those food sources. Every year timing is a bit different, as is the weather, but in general, if you come during the month of February you stand a very good chance of seeing the wildebeest herds (they can be on the move every day, so it may take some time to figure out where they’ve gone since the day prior).