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Migration · 7 min read

The Ndutu calving season: when it happens and what you will see

Eight thousand births a day, and everything that follows them.

Active Kili Top · Arusha · Updated 3 October 2026
A wildebeest mother and her calf on green grass
A calf can stand within minutes of being born.

The Ndutu calving season is the part of the migration that stays still. From about December to March the wildebeest herds settle on the short-grass plains around Ndutu, at the south-eastern edge of the Serengeti, and most of the year’s calves are born there within a few weeks around February. For a traveller it is the most dependable time of year to find the herds, and the hardest to watch.

This article covers where Ndutu is and why the herds come back to it, where the famous figure of eight thousand births a day comes from, which weeks to choose, what the predators do, and how to plan the days. It goes deeper on one season than our month-by-month migration calendar, which is the place to start if you have not yet settled on a month.

The short answer

The Ndutu calving season runs from about December to March on the short-grass plains of the southern Serengeti and the Ngorongoro Conservation Area. Most wildebeest calves are born within a few weeks around mid-February, at a commonly quoted rate of about 8,000 a day, with lion, cheetah and hyena close by.

At a glance: the calving season at Ndutu by month

The herds follow rain, not dates. In a dry spell they can leave the short grass for days at a time.
MonthWhere the herds usually areWhat to expect
NovemberReturning south through the parkShort rains; herds strung out and travelling
DecemberArriving on the southern plainsGreen grass, herds gathering, few calves yet
JanuaryOn the short grass around NdutuHerds settled; first calves late in the month
FebruaryNdutu and the southern plainsThe calving peak, with predators close by
MarchStill in the south, spreading outCalves on their feet; rain building
April and MayLeaving for the centre and westLong rains; Ndutu is the wrong place
Next: Where Ndutu is ↓Contents ↑

Where Ndutu is, and why the wildebeest calve there

Ndutu is not a park. It is an area of acacia woodland, marsh and two shallow soda lakes, Ndutu and Masek, at the head of the Olduvai Gorge. It lies inside the Ngorongoro Conservation Area, hard against the boundary of the Serengeti National Park. There is no fence and no visible line. The short-grass plains run on in every direction, and the herds graze across both.

The grass is the reason they come. Tanzania National Parks describes the plains between Naabi Hill gate and the Ngorongoro highlands as highly nutritious because of volcanic ash that fell there thousands of years ago. The shallow soil gives the grasses calcium, sodium, nitrogen and phosphorus, which is what a heavily pregnant cow, and then a nursing one, needs. The plains only grow when it rains, so the herds can use them for a few months of the year and no more.

For visitors the practical points are two. Ndutu is governed by the conservation area’s rules and fees, and the plains just to the north and west by the national park’s, so a day’s driving can involve both. And the rules on leaving the tracks differ between the two, which is why your guide will drive differently on either side of a boundary you cannot see.

Next: The 8,000 figure ↓Contents ↑

How many wildebeest calves are born a day

The figure repeated everywhere is 8,000 calves a day. It is worth knowing where it comes from, because nobody stands on the plains counting. It is an estimate, worked out from the size of the herd and the length of the birth peak. The park authority’s own leaflet for the Serengeti gives it as a range: more than 250,000 calves a year, four-fifths of them born in a few weeks around mid-February, at 8,000 to 12,000 births a day.

The science behind the short peak is solid. The biologist Richard Estes, who studied wildebeest in the Ngorongoro Crater in the 1960s and 1970s, found that more than 80 per cent of calves were born within two to three weeks. A 2018 paper in Scientific Reports puts the Serengeti total higher, at nearly 500,000 calves in about three weeks, from a population of roughly 1.25 million. So the commonly quoted half-million calves and the commonly quoted 8,000 a day do not quite come from the same sum.

The herd size itself is now in question. Aerial surveys have long put the migration at about 1.3 million wildebeest. A satellite count using machine learning, published in PNAS Nexus in 2025, found fewer than 600,000 in the images it analysed from 2022 and 2023, and its authors say the gap may reflect counting methods and not a collapse. The honest statement is this: several thousand calves a day at the peak, and nobody knows the number exactly.

Next: The months ↓Contents ↑

When is calving season in Ndutu: December to March

The herds usually reach the southern plains in December and stay into March. Our Ndutu Calving Season plan is built for those four months and rates January, February and March highest. Calving is concentrated around February. If you want the best chance of seeing newborn calves, the first three weeks of February are the ones to aim for, and they are also when the camps are fullest.

The timing is set months earlier. The rut, when the cows conceive, lasts less than a month around the end of the long rains, and gestation is about eight and a half months, which is why the births arrive together. The peak can fall a little earlier or later from one year to the next, and a dry spell in January can send the herds off the short grass towards the woodland or the west until it rains again.

January is green and often has a drier spell, with big herds and the first calves late in the month. March still has calves everywhere and good predator viewing, but the rain is building and a storm on black cotton soil can close a track for a day. From April the long rains set in and the herds leave. If you are travelling then, look at the central Serengeti instead.

Next: The predators ↓Contents ↑

Predators in calving season, and what is hard to watch

A wildebeest calf is on its feet within a few minutes of birth; the park authority says three to seven. It can keep up with the herd soon afterwards. That speed, and the sheer number of calves arriving at once, is the animal’s defence. Predators cannot eat more than a small share of a crop that appears all together. Estes found that calves born in large gatherings survived far better than those in small scattered herds, about 84 per cent against 51.

The predators come anyway. Lion, cheetah and spotted hyena are resident around the Ndutu woodland and marshes, and the open short grass makes hunts easy to follow from a distance. This is one of the better seasons in northern Tanzania for watching cheetah. Jackals and vultures work the edges. You are likely to see a kill, or the end of one, if you spend two full days on the plains.

Some of it is hard to watch. Calves are caught, mothers and calves lose each other in the confusion, and the park authority puts first-year losses at about 70,000 calves from predation, drowning and separation. Tell your guide at the start what you do and do not want to see. Nobody will drive you to a hunt you would rather miss, and there is plenty else on the plains.

Next: Planning the days ↓Contents ↑

Planning a Ndutu calving season safari from Arusha

Sleep at Ndutu. From the lodges at Karatu it is about three and a half hours over the crater highlands and down onto the plains, which is too far to do as a day’s outing and leaves you arriving after the best light. Our plan runs to six days: Lake Manyara on the way out, two nights at Ndutu in a seasonal tented camp, and a morning on the Ngorongoro Crater floor on the way back.

Two nights gives one full day and parts of two others. That is enough to find the herds if they are on the short grass, with little slack if the rain has moved them. A third night is the change we suggest most often, especially for February. If you want resident leopard and the Seronera valley as well, add two nights in the central Serengeti, or look at every plan that suits February.

Pack for the green season: a light waterproof, a warm layer for the early start, and a dust cover for the camera, because the plains are dusty between storms. Afternoon rain is common and rarely costs a whole day. Book early for February, when the few camps at Ndutu fill. If your dates fall between July and October, the herds are in the north, and the Mara River crossings are the thing to plan around.

Next: Questions ↓Contents ↑

Questions people ask

The herds are usually on the southern plains around Ndutu from December to March. Most calves are born within a few weeks around mid-February. The peak falls a little earlier or later from year to year, and the herds move with the rain.

The usual figure is about 8,000 a day at the peak. Tanzania National Parks gives a range of 8,000 to 12,000, from more than 250,000 calves a year. Some scientific papers put the total nearer 500,000. All of these are estimates, not counts.

Ndutu lies in the Ngorongoro Conservation Area, right on the boundary of the Serengeti National Park. The short-grass plains continue across the line without a fence, and the herds use both sides. Fees and driving rules differ between the two authorities.

For newborn calves, yes. February is the peak and the most dependable month to find the herds, and also the busiest. January has large herds and fewer vehicles. March has calves and predators but more rain.

Two nights is the minimum we would plan, giving one full day on the plains. Three nights is better, because a dry spell or a storm can move the herds and your guide then has time to find them again.

Possibly, but do not count on it. Most births happen in the morning and are over in minutes, in the middle of a large herd. You are far more likely to see calves a few hours or days old, still unsteady and close to their mothers.

Lion, cheetah and spotted hyena are the main ones, with jackals and vultures at the kills. The open short grass makes hunts visible from a long way off, and unhurried days on the plains give you the best chance of one.

Yes. December to March is the green season. Rain usually comes as afternoon storms, with a drier spell in many years during January and February. Tracks can become slow and muddy, which occasionally shortens a day but rarely cancels one.

Last updated 3 October 2026

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