Where the grass is shortest: reading the Migration in June

A moving season, not a place First, the correction every good guide makes in the first ten minutes: there is no such thing as 'the Migration' as a single location. There is a two-million-head decision loop following the rain, one wildebeest at a time, and the professional skill is knowing what the loop is doing this week.

The green-grass algorithm Wildebeest are simple creatures with one appetite: the shortest, greenest grass within a day's walk of water. The long rains fall in the south first, so the herds calve on the Ndutu plains in February. When the rains move north-west in May the plains dry to dust and the loop begins — through the Western Corridor's Grumeti in June, the north in July–August, the Mara River's crossings in September, and the long walk home on the October rain.

• December–March: south and east (Ndutu, Golini) — calving, predators, dust
• April–May: the corridor — long grass, few vehicles, dramatic skies
• June–July: Grumeti and the west — river number one
• August–October: Kogatende — the Mara crossings, the main event
• November: the fast walk home, racing the short rains

The radio network and the cousins Technology helps — everybody scans the WhatsApp ranger groups now — but the edge is older than that. Our senior guides come from the Serengeti's districts and still have family in the park villages. When the herds are between two rivers and the radios go quiet, that is when you want a guide who can make one phone call and hear 'the crossing built up at Number Three at four o'clock, the crocodiles are active'.

What this means for your dates If you tell us the month, we can tell you where the camp should be and roughly what you will see. The honest months are all good; they are just good differently. September buys the crossings, February buys the calving, June buys the emptiness. There is no bad answer — only the wrong camp for the week you are there.