I was just chatting to one of the guides and he told me that over the weekend some big crossings took place and then, during the week the herds started moving south, through Ikorongo and the Grumeti Game Reserve.
There's a large herds towards the west and on the way to Seronera - Retima and Serena as of yesterday afternoon. It also looked like it rained over that way recently, but still pretty dry around us, despite a few showers this past week, so I imagine the herds are looking for greener pastures.
Even so we have has a few smaller herds of zebra and wildebeest visiting our waterhole yesterday and this morning.
Small herd around the waterhole at the Four Seasons - Image by Oliver Dreike