The Serengeti-Mara wildebeest migration is the largest overland animal movement on Earth — 1.5 million wildebeest, 250,000 zebra, and 500,000 Thomson’s gazelle circulating in a clockwise annual loop across 40,000 sq km of Tanzania’s Serengeti and Kenya’s Masai Mara. The migration is not a single event but a continuous 12-month cycle driven by rainfall, grass growth, and the instinct to follow the nutritional gradient across the ecosystem. Understanding where the herds are in each month allows visitors to position themselves at the right location and time — whether for the January calving spectacle near Ndutu, the Grumeti River crossings in June, or the famous Mara River crossings of July-September. This guide traces the full annual cycle month by month.
December and January: Southern Serengeti Calving
By December, the wildebeest herds have returned from Kenya’s Masai Mara and accumulated on the short grass plains of the southern Serengeti — the Ndutu area near the NCA boundary, and the plains south of Seronera extending to the Tanzania-Kenya border at the base of the Gol Mountains. The short grass of the southern plains provides the specific nutrition wildebeest need for late pregnancy — higher protein content, lower fibre, and the mineral-rich young growth that triggers lactation. The calving season peaks in late January to mid-February. In this 3-week window, approximately 500,000 calves are born — the synchronised birth that overwhelms predators (too many calves to pick off efficiently) and ensures maximum calf survival through safety in numbers. The calving grounds are accessible from the Ndutu Safari Lodge area and the NCA western plains — a 2-hour drive from the Ngorongoro crater rim.
February: Calving Peak and Predator Feast
February is the Serengeti’s most dramatic predator month. The concentration of newborn calves (1-3 days old, unsteady on their feet) on the short grass plains attracts lion from the Ndutu and Lake Masek territories, cheetah (highest density anywhere in Africa near Ndutu in February), spotted hyena clans of 50-80 individuals, wild dog packs, and the ever-present black-backed jackals. The predator viewing in February is unmatched — hyena crèche sites with cubs watching the hunt, cheetah mothers teaching 3/4-grown cubs to run down young calves, and lion prides feeding on wildebeest daily because the prey is so abundant it barely needs coordinated hunting. February at Ndutu is one of Africa’s finest safari months and remains relatively uncrowded compared to July-August.
March, April and May: Long Rains, Western Serengeti
The long rains (March-May) drive the herds northwest. As the southern plains grass desiccates and the rains move north and west, the wildebeest follow — first to the central Serengeti around Seronera (March), then progressively northwest toward the Western Corridor (April-May). The Western Corridor (Kirawira area, Grumeti River) receives the herds in May-June as the grass quality of the western slopes attracts the leading herds. This period receives fewer visitors than peak season but the Western Corridor is genuinely excellent in May — large herds accumulating near the Grumeti River before the first crossings, with very few vehicles sharing the sightings. Accommodation on the Western Corridor: Kirawira Serena Camp (USD $300/night per person), Grumeti Serengeti Tented Camp (Singita, from USD $1,500/night), and the budget Ndabaka Gate campsite (USD $30/person).
June: Grumeti River Crossings
The Grumeti River crossings are the “forgotten crossings” — less photographed than the Mara River events but equally dramatic in their own way. The Grumeti’s distinguishing feature: the river’s enormous resident Nile crocodile population, including some of Africa’s largest individual crocodiles (5-5.5m, 800kg+ individuals). The Grumeti crocodiles are fewer in number than the Mara’s but larger individually — the scale of a single 5-metre crocodile ambushing a wildebeest is viscerally spectacular. The crossings occur at identified points near Kirawira and the Retima Hippo Pool area. June in the Western Corridor: beginning of dry season, excellent photography light, far fewer vehicles than the Mara River crossings of July-August, and wildlife already excellent (lions active, elephant herds at the Grumeti).
July and August: Northern Serengeti and Mara River
The herds push north through the Lobo and Kuria Hills area in July, reaching the Mara River by late July-early August. The Mara River crossings (north of Kogatende ranger post in the northern Serengeti, and on the Kenya side across the border in the Masai Mara) begin in late July and continue through August. The northern Serengeti (Kogatende area, accessible from Klein’s Gate) receives significantly fewer vehicles than the Masai Mara side of the same river — identical crossing events, identical crocodile action, and a fraction of the vehicle density. Self-drive visitors should consider positioning in the northern Serengeti in August rather than crossing the border to the Mara side for the crossing experience without the vehicle crowd.
September and October: The Return Begins
The short rains beginning in late October trigger the return movement south. From mid-September through October, the herds gradually drift southward out of the Mara and through the Lobo area back toward the central Serengeti. The return crossings (herds re-crossing the Mara River back into Tanzania) occur in September — a crossing event that is less predictably timed than the northward crossings but equally dramatic when it happens. October in the Serengeti: herds spread across the eastern and central plains heading south, excellent predator activity (lion and cheetah following the herds), and very manageable visitor numbers as most tourist traffic has followed the calendar to “peak season is over.”
November: Short Rains and Arrival Back South
November’s short rains bring the herds back to the central and southern Serengeti. The plains green up rapidly after the first rains, and the wildebeest begin the nutritional rebuild that will support the January calving. By late November, the bulk of the herd is back in the Serengeti’s central and southern sections. November is an underrated game-viewing month — rain typically falls in brief afternoon showers rather than sustained downpours, the Serengeti is green and beautiful, and wildebeest numbers in the central plains create excellent wildlife density. November accommodation prices are at shoulder rates — the post-October price reduction before Christmas demand.
Best Positions by Month: Quick Reference
- January-February: Southern Serengeti / Ndutu area (calving)
- March-April: Central Serengeti / Seronera (transition)
- May-June: Western Corridor / Grumeti River (first crossings)
- July-August: Northern Serengeti / Kogatende or Masai Mara (main crossings)
- September-October: Northern Serengeti return / Central Serengeti (return migration)
- November-December: Southern Serengeti / Ndutu (pre-calving accumulation)
