The plains and savannahs of East Africa are known for their massive number of wildlife. In addition to the big five, the great wildebeest migration is one of the most fascinating events that continues to draw wildlife enthusiasts, researchers, photographers and tourists from all over the world to this region.
But the Great Wildebeest Migration is not just a spectacular natural event or an ordinary tourist attraction. There is more to this natural phenomenon than meets the eye. In this article, we will highlight some interesting facts about the Great Wildebeest Migration. From the massive number of herds involved, to how they overcome the obstacles and survive during the migration, how the animals co-exist to the impacts their mass movement has on the Serengeti–Mara Ecosystem.
Though it is dubbed as The Great Wildebeest Migration, it is not just the Wildebeests that undertake the journey. Although the Wildebeests are the majority in herd, they migrate together with numerous Zebras and other few antelopes, such as Grant’s gazelles, Thomson’s gazelles, Elands and Impala. They migrate together in a clockwise movement following rainfall.
The migrating herds’ safety lies in numbers. While the number of animals taking part in the migration fluctuates in every migration cycle, it is estimated that close to two million animals take part every year. Out of these, Wildebeests which dominate the herds account for over one million, Zebras over 200,000, Thomson’s and Grant’s gazelles over 350,000, and around 20,000 Elands and Impalas.
The mass movement of Wildebeests happens all year round. While the river crossing is the most coveted event in the migration cycle, you can witness migration all year round. The other major events in the migration cycle include birthing season and rutting season. The Wildebeests are constantly migrating across the Serengeti-Mara Region every year. Once the grass is depleted in one location, they move to the next, searching for water and new grazing fields until they complete the entire cycle. This means you can catch the migration all year round in different places.
Every year, over 1.6 million animals spend most of their year circling across Tanzania’s Serengeti and Kenya’s Masai Mara in search of greener pastures and water. The migrating herds cover over 600 miles during each cycle. The sheer number of animals involved also makes it one of the largest mass migrations of wildlife in the world.
Although close to two million animals are involved in the migration, they don’t all stick together. As these grazers move towards Maasai Mara, they spread out and split into ‘smaller’ herds, with each herd consisting of about tens of thousands of animals. And some of these smaller herds follow a slightly different route, while still moving in the same direction towards the Mara River. At some point along the migration cycle, they do merge and then split. This is one of their survival tactics. If all the animals moved together, they would deplete the grass, leading to massive deaths from starvation. The best season to see almost the entire wildebeest herd congregated in one location is during the calving season in the plains of the Southern Serengeti and Ngorongoro Conservation Area.
Just as all the wildebeest don’t move together every time, they also don’t cross the Mara River at the same time. Though the river crossing usually happens from August to October, there are different herds crossing at different times during this season. Sometimes you can watch very huge herds crossing continuously uninterrupted for hours, whereas at other times there are only a few hundreds crossing.
The migrating herds also don’t cross at the same point. There are multiple crossing points along the Mara River which the Wildebeests use.
Besides being a natural spectacle, Wildebeest Migration also plays a significant role in maintaining a healthy ecosystem. Their cyclic movement ensures they get enough nourishment, which is important for their survival. This prevents overgrazing and maintains a healthy population of Wildebeests. In return, this gives predators enough food to sustain them. This creates a healthy predator-prey balance, which is essential. Also, the grazers droppings nourish the soil, giving rise to new grass and plants which support all the other herbivores in the wild.
Every year, January to March signals the calving season in Serengeti. During this time, nearly half a million calves are born. Interestingly, over 80% of the calves are born in a period of 3 weeks starting from mid-February. This mass birthing plays a great role in the safety and survival of the newborn wildebeests.
Another interesting fact about the Wildebeests is that during the calving season, majority of the females give birth to their young before noon. This gives the newborns enough time to learn how to walk and to bond with their mothers before most predators become active in the late afternoon and evening.
Interestingly, in just 5 minutes after being born, Wildebeest calves can stand up and walk besides their mother. And within the next fifteen minutes they can run together with the rest of the herds. Their ability to walk and run almost immediately after birth is vital in their survival in the wilderness, as they need to evade predators and keep pace with the rest of the herds.
You’re probably wondering how are Wildebeests able to distinguish their newborns from the rest whereas over 8,000 calves are being born in every single day during calving season. Interestingly, Wildebeest mothers can identify their individual young. They develop a strong bond as they lick their newborn afterbirth and while breastfeeding them. The newborns also stay and walk close to their mothers not only for protection, but it also gives them ample time to recognize and remember their scent and voices.
Another interesting thing about the calf-mother bond is that female Wildebeests nurse their young only and don’t tolerate other calves, in the wild. In instances when they get separated, like when running away from the predators, they locate each other via their calls. Young ones that are not able to reunite with their mothers are at high risk of dying from starvation.
Zebras and Wildebeests coexist peacefully with each other as they journey through the African plains. The reason being they have a great symbiotic relationship. Each of them has their own unique qualities that boost the survival chances of the herds in the wilderness. Though both are grazers feeding on the same plant, they live and migrate together without competition. This is mainly because they eat different parts of plants, with Zebras preferring to feed on the longer and tougher or course grass while leaving behind the shorter grass for the Wildebeests.
Also, Zebras have great vision which enables them to spot predators from afar, allowing the herd to avoid them. On the other hand, Wildebeest have a great sense of smell that helps them to find water.
It is estimated that more than 240,000 Wildebeests and 40,000 Zebras, gazelles and impalas die each year during the migration cycle. The major causes of death include being killed by predators, fatigue, starvation, and drowning.
While the Wildebeest river crossing to and from Maasai Mara Reserve from August–October is the most famous stage of the migration, Wildebeests spend nine months grazing and migrating through Tanzania and around 2-3 months on the Kenyan side. Most of the migration happens in Serengeti National Park, Loliondo Game Controlled Area, Ngorongoro Conservation Area, and the Grumeti Reserve.
Unlike other social animals such as Elephants, Chimpanzees and Lions, Wildebeests don’t have a leader. This means that their movement is not determined by an individual Wildebeest rather, their collective behavior arises from swarm intelligence. Because of this herd mentality, tens of thousands of Wildebeests move in sync towards the same direction at the same speed. Wildebeests swarm intelligence enables them to navigate their obstacles, avoid predators, and find greener pastures more easily as a group than they would individually.
While the migration pattern (calving season in southern plains- movement north in Central Serengeti- grazing in the Western Corridor and Grumeti River crossing- Mara River crossing- grazing in Maasai Mara Reserve) remain fairly constant during each migration cycle, the exact timing for the migration varies every year. Rain, availability of food and water and sometimes the predator’s behavior influences the timing of the movement.
By going through the facts above about Wildebeest Migration, we get to appreciate that these facts go deep beyond being merely interesting. They reveal the intricate strategies that are vital for these herds to survive and thrive in the wild. From their cyclical movement and strategic grazing patterns to massive numbers of animals moving together, collective actions, synchronized mating and mass birthing of calves and calves gaining their muscle strength and coordination shortly after birth every one of these strategies however small, plays a great a role in making the Wildebeest Migration the spectacle it is .