The Ultimate Guide to the Great Wildebeest Migration

 

To be able to enjoy this ultimate safari highlight, travellers should at least know a little bit more about the phenomenon itself, what they can expect from it, and of course, it is also always good to receive a few tips from other experienced travellers to heed while visiting the relevant area for the first time.

  What is known as The Great Serengeti Wildebeest Migration is the annual movements of a vast number of the Serengeti’s wildebeest, accompanied by large numbers of zebra, and smaller numbers of Grant’s gazelle, Thomson’s gazelle, eland and impala every year in patterns which seem to be fairly predictable. These animals keep on migrating throughout the year, constantly in search of fresh grazing and, as some knowledgeable people would have it, also in search of cleaner and better-quality water. Due to the magnitude of the event, it became known as the Great Wildebeest Migration. The Great Wildebeest Migration is often classified as one of the “Seven New Wonders of the World”, even one of the ten Wonders of the World, while others, presumably those with a more sporty attitude to life, has dubbed it as The World Cup of Wildlife. Whatever you may call it, if there is one safari every nature lover should consider putting on his itinerary, this must be the one. Nowhere else in the world is there a movement of animals exactly as huge as this migration of wildebeest and other animals, when often more than two million animals decide to migrate from the Serengeti National Park in Tanzania to the greener pastures of the Maasai Mara National Reserve in Kenya in their search for food and water. It speaks for itself then that the Maasai Mara and the Serengeti National Park together form a tourist and safari destination what hardly any other reserve or park in Africa can. It just is an incredible, magical, almost indescribable destination and it is a must to be visited at least once during a lifetime. This article aims to give an overview of the Great Wildebeest Migration as phenomenon and Maasai Mara as one of the ultimate safari destinations, as gathered from several sources and experts on the region.  

What makes a million wildebeest get up and move at once?

  The questions may tend to remain more than the answers but need not deter any traveller from visiting the area. Whatever the sense might be that triggers them to gather the energy and begin an approximate 1000-kilometre trek, and for some unknown reason to just know that it is the right thing to do every year, may remain a mystery to humans. What we do know however, is that wildebeest inhabit the plains and open woodlands of many parts of Africa south of the Sahara. The black wildebeest is mostly found in the southernmost parts of the continent like in South Africa, Eswatini, and Lesotho, and also introduced to Namibia, where it has become well established. The blue wildebeest is native to eastern and southern Africa, with the range where it is found including Kenya, Tanzania, Botswana, Zambia, Zimbabwe, Mozambique, South Africa, Namibia, Swaziland and Angola. They are often found in the kind of habitats that vary between overgrazed areas with dense bush and more open woodland floodplains. The blue wildebeest is the most abundant big game species in East Africa, both in biomass and population and large herds of them can be found in the Serengeti National Park in Tanzania, the Maasai Mara National Reserve in Kenya and the Liuwa Plain National Park in Zambia. Not all of the wildebeest are migratory. Black wildebeest herds are usually nomadic or may prefer to stay within a regular smaller home range of about one square kilometre. Spacing will vary according to the quality of the specific habitat, but wildebeest bulls may usually occupy territories of about 100 to 400 m apart. Blue wildebeest have both habitat bound and migratory populations. Interestingly enough, in the Ngorongoro, not far from where the Great Migration takes place every year, most wildebeest are habitat bound and males maintain their network of territories throughout the whole year. Their breeding is seasonal in nature, though with females and young calves forming groups of about 10 individuals or join together in larger aggregations. The nonterritorial males also form bachelor groups. In contrast to Ngorongoro, populations are mostly migratory in the Serengeti and Tarangire ecosystems, with the herds frequently moving and also consisting of both sexes. During the rutting season, the males may form territories temporarily, for a few hours or a day or so, in an attempt to gather together a few females with which to mate. These however dissolve soon when they have to move on, often moving ahead just to set up another temporary territory. In almost all game reserves one finds that wildebeest like to graze in mixed herds with zebra, presumably because such cooperation would give both species a heightened awareness of the possible proximity of potential predators. Apparently, they are also quite alert to many of the warning signals that may be emitted by other animals, such as baboons, when they sense any kind of danger. The long-distance migration seen each year with some East African populations of blue wildebeest, is seemingly timed to coincide with the annual pattern of rainfall and grass growth in those areas. Their timing of the migrations in both the rainy and dry seasons can vary considerably from year to year and it is hardly ever possible to forecast in which month it will happen. At the end of the wet seasons, which usually occur around May and June in East Africa, the wildebeest migrate in response to a lack of surface drinking water to areas where they can find water. When the next rainy season again begins a few months later, the animals move back to their wet season ranges again. Factors like the abundance of food, availability of surface water, presence of predators, and phosphorus content in grasses are suspected to affect migration times and patterns. Phosphorus is a vital element for all life forms and specifically for lactating female bovids, hence wildebeest select grazing areas that contain very high phosphorus levels during rainy seasons. It is also suggested that, in addition to phosphorus, wildebeest instinctively select ranges with grass containing relatively high levels of nitrogen. While the Great Wildebeest Migration has the appearance of a frenzied act to the untrained eye, research has suggested that those herds of wildebeest possess something like a “swarm intelligence”, whereby all the animals in the herd systematically explore and subsequently overcome the obstacles in their way as one entity. This is supported by aerial photography that has shown that there is some level of organisation in many of the movements of the herd that cannot actually be apparent to each individual animal at the time. For example, the migratory herd seems to show a kind of wavy front, which may suggest that some degree of local decision-making is taking place while they are moving.  

Why does the Great Wildebeest Migration take place?

  One may ask why, when most wildebeest in Africa are non-migratory, the animals of the Mara and Serengeti ecosystems do risk it all (many loses their lives to crocodiles while crossing the rivers) in one seemingly mad trip? Not one scientist or naturalist has thus far been able to conclusively answer this question, but several theories have been formed over years by studying the behaviour of these animals. Some of the studies that used aerial photography showed an amazing level of some kind of organisation in the structure of the wildebeest herds when they start moving. The groups tend to display a wavy front that snakes out like the head of a swarm. Since this structure cannot be known to each individual animal, it means that there must be some degree of decision making between the animals. Many scientists believe that the wildebeest behaviour are motivated and triggered by the chemistry of their food – the grass. The herds may be attracted to higher levels of phosphorus and nitrogen, which both will change according to factors like rainfall. Could the wildebeest perhaps be connoisseurs that are merely following their taste? The most obvious of course may be that they are simply following their instinct. Fossil evidence wants to have it that wildebeest have been roaming the plains of East Africa since at least the last million or more years. It just could be that the instinct to migrate has been encoded into the DNA of the species over many years of evolution in the same way their body tells them to run when a lion appears out of the grass. The fact is that they just know, and then they just go. Whatever the reason may be, more than one and a half million animals annually begin an epic journey that will indisputably cause death to many of them and especially their young, but will fortunately bring life to the many more surviving animals as they duly follow the rains in search of greener fields with nutrient-rich grass to sustain the next generation.  

What numbers are involved in the Great Wildebeest Migration?

  The Great Wildebeest Migration is said to be the largest overland migration in the world, with the animals travelling at least 800 km or more during each annual cycle. The sheer magnitude of the event adds much to the magnificence of the phenomenon and marks it as one of the top tourist experiences any traveller may witness. When herds consisting of between one and a half and two million wildebeest, zebras and other species tread or sprint across the Serengeti in Tanzania and the Maasai Mara in Kenya in search of better grazing options, you would give anything to be one of the lucky once to be on safari in the region to witness the adventure. It is of course very difficult to get accurate figures of the numbers of animals annually taking part in the migration, but it is estimated (perhaps conservatively, perhaps overestimated) that in the region of between one and a half million and 1,7 million wildebeest, 250 000 Burchell’s zebra and a smaller number of trailing Thomson’s gazelle make the yearlong, round-trip trek from Tanzania’s Serengeti to Kenya’s Maasai Mara each time. This all happens in the area that is loosely known as the Serengeti Ecosystem, which comprises about 40 000 square kilometres and includes some parts of the Ngorongoro Conservation Area in the south; the Serengeti National Park and the adjacent Maswa Game Reserve, as well as other ‘controlled’ areas in the centre, east and west; and the Maasai Mara National Reserve to the north. The wildebeest are the main participants in this act, and it is currently assumed that their numbers might have settled at just under 1,7 million. Supporting roles are taken up by more or less 400 000 Thomson’s gazelle, another 300 000 or more zebra and also about 12 000 eland. These animals are the main migrators, and, on their journey, they cross the ranges of more than a quarter of a million other resident herbivores and carnivores. Among the carnivores the prides of lion, hyenas, leopards, cheetahs and other lesser predators each year await the annual event of the migration with the same eager anticipation – after all, they are also permanently in search of food. From the above it also becomes clear that, in reality the single concept of ‘the migration’ is not true. There is no such single entity, but rather that the wildebeest in itself is the migration, since there is neither start nor finish to their endless quest to search for better food options and lifegiving water. They continuously circle through the whole Serengeti- Mara ecosystem in an unyielding sequence of birth, life and death.  

How does the Great Wildebeest Migration work?

 

The circle starts

  Towards the end of the short and dry season in the southern Serengeti, which usually is around March, the plains filled with short grasses begin to dry out, causing the wildebeest to begin and continue on a journey that heads towards the western woodlands. There are more than one possible answers on how they know which way to go, but it is believed that the wildebeest’s journey is primarily dictated by their response to the weather. They tend to follow the rains and the subsequent sprouting and growth of new grass. Although no scientific proof exists yet that it may be true, it is suggested that the wildebeest and other animals that migrate with them, may perhaps react to the presence of lightning and thunderstorms in the distance. It also may just be instinctive knowledge, imprinted into their DNA by natural selection and hundreds of thousands of years of the same behaviour. It seems quite probable that this would be the major reason why these animals just know in which direction they must travel. Over thousands of years, it there were wildebeest that went the ‘wrong’ way, they would have died of thirst and starvation before they could reproduce. It is simple logic that those that lived to produce future generations, were the ones that went the ‘right’ way and survived. The migrating herds head west from the plains around Olduvai towards the small lakes Ndutu, Masek and Lagarja, since at this stage they are mainly needing and looking to find water, which the more westerly areas can provide. During this stage they can still feed and are fattening on the nutritious short grass, with the herds widely scattering across the plains, moving around according to their instincts to find all edible and the most nutritious grass.  At this stage one may find several widely spread out herds all across the spacious plains west of Ndutu, just to be gone the very next day. By now the first torrents of the “long rains” may start to fall, and the wildebeest will trot across the plains towards the expected distant thunderstorms. Locals like to refer to the rainy seasons as the “long rains” which falls for approximately six to eight weeks in April and May and the “short rains” which falls in November and December and lasts approximately for four weeks. If the promise of rain does not match the reality, they will return to their position a day or two later, just to try again when the signs are there.  

The annual rut season

  When the rains have commenced, the herds head in a north-western direction and pass the granite ridges of the Moru and Simba kopjes and go in the direction of Lake Victoria into the woodlands of the mountainous country west of Seronera. Now is also the time of the annual rut, the periodic and annually recurring state of the males during which their behaviour is associated with the urge to breed and about half a million cows are mated in less than a month.  The peak of the rut seems to be influenced by the state of the moon, with the full moon in May and June being a good time for anyone seeking to witness the most action. This rutting time is also marked by apparent vicious fighting between dominant or territorial males, although it does not really contain actual violence and serious injury is hardly ever inflicted. Much of this ado may also be in vain, because in actual fact and despite all these spirited duels, the males have little say over their choice of mates. It is the females who make the actual choice of mate! Wildebeest cows drop their young in January and February in a synchronised birthing that sees some 300 000 to 400 000 calves born within two to three weeks of one another, eight and a half months after the rut. The birthing occurs on the short-grass plains at the southernmost extent of the wildebeests’ range, spread over the lower northern slopes of the Ngorongoro Crater highlands.  

The famous crossing to the Maasai Mara

  Now it is time for the wildebeest to move on again. The next part of their journey stretches from the western Serengeti northward, following the effects of the rains (or the rain itself) into Kenya and the Maasai Mara Game Reserve. On this trek the wildebeest have to cross at least a few rivers: in the Serengeti they have to cross the Mbalangeti and the Grumeti rivers, and in Kenya they have to cross the Mara River. Although these rivers are for most of the year relatively placid, they can become quite violent torrents of water depending on the amount of rainfall in their respective catchment areas.  In that case all these rivers – and even a few isolated lakes in the south of the Serengeti – present major obstacles for the wildebeest during their progress. Firstly, the animals have a natural fear to go into the water because they are aware of all the dangerous creatures like crocodiles that it may hide, and secondly because there are usually more vegetation around the water which in turn may conceal some predators. None of these fears however deter the wildebeest and their inherent instinct urge them to trek in their chosen direction at any cost and despite any fears. Another interesting feat of nature also steps in here: The Ndutu, Masek and Lagarja lakes in the south are, for example, a little longer than a few kilometres and they could easily rather be walked around. But apparently natural selection needs to take place too. The wildebeest that crossed through the lakes previously, survived and bred, so the waters pose no fear to their offspring too. The ones that did not make it, had no further input to the gene pool and so it would continue for all times. Although the fact that thousands of wildebeest had died in the lakes and rivers over years is tragic, and such tragedies may appear to be disastrous for the wildebeest, the deaths in fact only represent a handful of the hundreds of thousands of calves born each year. Without this degree of natural mortality, the population would have spiralled out of control. Perhaps the most famous crossing though, is waiting at the Mara River. Wildebeest arrive there in their tens of thousands, where they gather together, waiting to cross. Their numbers can build up for days and for no apparent reason they hesitate and even turn and wander away from the water’s edge many times while the anticipation grows. Eventually however they will choose a point to cross, and not necessarily the same crossing point as previous years. Nobody can predict with any accuracy where they will cross any specific year. Usually the chosen point will however be a fairly easy-going, placid stretch of water without too much vegetation on the far side which could conceal predators. Once and again though they may choose seemingly suicidal places to cross and then drown in their hundreds. One can just wonder whether this also may perhaps be because certain crossing places were genetically imprinted in the minds of some animals. Some crossings also attract larger numbers of animals than others, presumably because they may be visible from far away by arriving herds, which may decide to follow those in the process of crossing the river or already grazing on the grass on the far side.  

Hungry predators are awaiting their turn around every corner

  Once the grasslands of the Maasai Mara have been reached, the wildebeest will spend several months feeding and fattening on the green pastures. It is remarkable how they are able to find areas of good grazing all the time, no matter how far it may be apart. Wildebeest are built to easily travel large distances quickly and economically, without requiring much more energy to run than to walk a distance to feed. They even mate on the move, and new-borns are up and running and able to follow the herd within minutes after birth. Calving season is a bonus for predators, and the reserves also boasts a healthy lion population. All across the plains literally hundreds of hyenas and dozens of lions can be seen scattered about. It almost seems as if the wildebeest are doing the predators a favour by dropping their young all at the same time, but in fact such excess of wildebeest veal in the very short time satiates the predators to such an extent that they are unable to consume as much as they would if the calving happened over a longer time span. Thus, the predators actually have only a limited impact on the population of newborn calves and the calves born outside the peak time are more likely to perish. The fact that wildebeest are constantly on the move has the added benefit though that they outmarch many predators. Predators, many of whom are territorial and can neither abandon their territories nor invade those of others, cannot follow the moving herds of wildebeest very far. The predators also can’t move very far from their own young.  

Completing the circle

  By late October it is time again for the “short rains” on the Serengeti’s short-grass plains. Now seasonal waterholes are filling up and the rain brings new growth. This is the signal to the wildebeest that it is time to start heading south again. The herds start trekking down through the eastern woodlands of the Serengeti, first tightly grouped with many of the cows heavy with the young of the new season but spreading out again as they reach the open plains. This more or less complete the clockwise cycle of the migrations between Tanzania and Kenya. It can be seen that most of the movement actually takes place in Tanzania – Serengeti National Park, Ngorongoro Conservation Area, Loliondo Game Controlled Area, and Grumeti Reserve – with the part in Kenya stretching to the Maasai Mara Game Reserve, which borders the north of the Serengeti National Park.  

When does the Great Wildebeest Migration take place?

  There is little to no predictability about the migration process and questions as to which would be the best month to view it, will get as many different answers from as many different people you may ask. It is a very dynamic process with a lot of variables, all of which defies any accurate predictions. No two years will ever be quite the same. Probably the most important element that influences the migration, is the weather and the cycle of four seasons per year undoubtedly has the defining influence on the migration. The seasons are reasonably defined: a ‘short dry season’ that is typically experienced from December to February or March; the ‘long rains’ that fall over a six week period from March through April and into May; and the ‘long dry season’ which is from June to September, with the two-week ‘short rains’ falling any time from October into November. There are, however, no guarantees about any of these dates. The precise timing of any stage in the Serengeti wildebeest migration is entirely dependent upon the rainfall patterns each year. The traveller that wants to go on a once in a lifetime safari to witness this, should decide what he or she wants to see the most, because this will impact on the timing and location of the planned visit. Broadly speaking, you must choose between river crossings, massive herds of animals as far as the eye can see or the calving season. You will be able to witness predator action at all times and stages. A month to month summary of the migration may help you decide.  

A month to month overview of the course of the Great Wildebeest Migration

 

January:

  The first rains in the southern Serengeti plains beckon the herds to the Ndutu area. If you want to find the wildebeest in January, you should be near Naabi Hill and Lobo, because many females in the herd are heavily pregnant and are moving towards greener grasses.  

February:

  February is the month that often sees as many as 8 000 new calves born each day, often in the area around Lake Maek and Lake Ndutu due to abundant new grass in the area. A newborn wildebeest gains co-ordination faster than any other ungulate and it can usually be on its feet within a mere two to three minutes after birth. It is able to run with the herd as soon as it is about five minutes old and may be able to outrun a lioness soon thereafter. Calves easily get separated from their mothers when a herd panic, which happens quite frequently, or while they cross rivers or lakes in their path. Since no wildebeest cow will adopt a strange calf, even if she has lost her own and is lactating at the time, such lost calves soon become easy victims for any watching predators, from jackal up to hyena and lion. After the calves are born the herds may then stay in the southeast Ndutu area for a while, before heading north in a clockwise direction.  

March:

  Now you can find the herds in the Ndutu and Kusini Maswa region in the south-west of the Serengeti. Having lots of babies with them, means they move slower. The mobile camps in the park provide the ideal venues for close and personal experience of the migration.  

April:

  During April the herds, that by now have split into large groups, move from the Ndutu region, past the Simba kopje, in the direction of Moru. Simba kopje is where you will most probably see the lions too, making it worthwhile to spend some time lion “hunting” too. On a visit in April, you are going to need your rain jacket for rainy evenings and since the rain also makes the plains slippery, vehicles without 4×4 traction will battle to go anywhere.  

May:

  May is the month for photographers in the Serengeti. With the ‘long rains’ keep on falling throughout the month, the calves get bigger and stronger and the herds can cover longer and longer distances per day. You are likely to find them between Moru and Mokoma, on their way towards Lake Magadi.  

June:

  By June, the herds have spread out due to lesser rain. The front-runners may already have reached Mbalageti River by now, while those in the rear could still be as far back as Lake Magadi or near the Simiti and Nyamuma Hills. As they head north, the herds are often forming long lines as they move along.  

July:

  July is mating season in the Serengeti and you will find the herds in the Grumeti Reserve, in the west of the Serengeti, and moving past Fort Ikoma. It may be worthwhile to wait for some possible crossings at the Grumeti River, but the Serengeti is vast and relatively under-developed with lodges in this area, so river crossings are not that accessible. The Grumeti River also does not have as much water as the Mara River, hence the crossings not as spectacular. The herds keep on grazing their way northwards toward the Maasai Mara in Kenya.  

August:

  By August, the herds could have made their way up to the northern Serengeti, where they have to face their biggest challenge yet: the Mara River. The Mara River is a fast-moving river and the crossing usually offers dramatic sightings, varying from animals plunging in their masses off the steep banks in a desperate attempt to get across the river (or away from lions) with the fall alone killing some individuals; to drownings as they are crushed by just as many panicking wildebeest trying to scramble up the equally steep banks on the other side. In the murky waters are more enemies: hungry crocodiles yearning for a dinner too. Every death means dinner for these crocodiles, birds and fish, while big cats and hyenas pick more off the stragglers and the injured. These river crossings attract large volumes of tourists who congregate at strategic points to witness this spectacle.  

September:

  During September you may still be lucky to catch the tail end of the Mara River crossing or otherwise you can go and see the herds out in the open plains of the Maasai Mara. At this time, the weather there will be hot and dry.  

October:

  While the Maasai Mara is a smaller reserve as the Serengeti, your best bet is to be in the Maasai Mara now. It may still be quite crowded at this time of year, due to a lot of visitors. The conservancies around the Mara may be less crowded now, so you can also head there. Not only will you still be able to witness the migration itself, you will also contribute directly to the welfare of the Maasai communities who have lived there for thousands of years.  

November:

  What is known as ‘the short rains’ begin in November, triggering the start of another move, with the herds now leaving Kenya and going south to western Loliondo and the Lobo area in the Serengeti National Park. At this point, the herds organise themselves into smaller family groups and continue grazing on the nutritious grass.  

December:

  By December, the herds are back in the south of Serengeti, and the whole migrating act begins all over again.  

The Great Wildebeest Migration in a nutshell

 

• Some fascinating Great Wildebeest Migration facts to remember when you are planning your ultimate safari:
• The Great Migration sees about 1.7 million wildebeest, 250 000 zebra and a host of other antelope travelling cross country.
• Each year between January and March, half a million or more wildebeest are born in the Serengeti. In February, the month with the highest calving rate, around 8 000 wildebeest may be born each day.
• The Great Wildebeest Migration is the largest overland migration in the world, with the animals travel a total of about 800 km or more during each cycle.
• Research suggests that a herd of wildebeest possess what is known as ‘swarm intelligence’, where they systematically explore and overcome an obstacle as one. Thus, although the migration may seem like a chaotic frenzy of movement, it is actually well construed.
• Zebra and wildebeest like to graze in harmony together because they each eat different parts of the same type of grass.
• A migrating herd of wildebeest often splits up into smaller herds that circle the main herd, because wildebeest do not have a natural leader. In this way, the groups of smaller, split herds can cover over half of the whole Serengeti during the whole migration.
• The Serengeti National Park eco-system is the oldest on the planet and boasts a diversity of plants and animals unavailable anywhere else in the world.
• During the migration of one year up to a staggering 250 000 wildebeest and 30 000 zebra will probably be killed off due to predation by carnivores, but also from thirst, hunger, and exhaustion.
• The crocodiles in the Mara River that await the herds drown their prey by clutching them in their strong jaws and pulling them below the water, twisting them in order to break off bite-size pieces.
• More than 3 000 lion also living in the Serengeti ecosystem will follow the migratory herds across the reserve each year.
• When the rains beckon, the wildebeest go, notwithstanding the fact that they know the predators are waiting and the rivers teem with crocodiles, they just follow their inner compass in the circular journey every year.