Wldebeest migration in Serengeti continues year after year. This year, the pattern of migration is more or less the same. The rains, that translates in green grass for the wildebeest, is the major determinant of the movement. This year, the Serengeti has experienced less rains than usual. That being the case, the movement from south Serengeti to north Serengeti has started earlier, and, crossing Mara River might be earlier as well.