Two such migrations are those of the zebras in Botswana one of which is the longest mammal migration in Africa. These migrations offer astounding (and often less crowded) wildlife sightings but, more importantly, they are testament to not only the resilience of nature in the face of human interference but to the genetically programmed instinct to migrate.
In the late 1960s, Botswana entered into an agreement with the European Union to provide cattle for food purposes, but while this deal may have been lucrative at the time, it came with stringent conditions. One of these was that Botswana needed to take measures to avoid the transmission of foot-and-mouth disease between wild animals and domestic cattle. Thus, a series of veterinary fences were erected that separated swathes of land and cut off the pre-existing migratory routes. When these fences were moved in the mid-2000s, researchers and conservationists were astounded to see a portion of the zebra herds begin to follow ancient migratory patterns: the Chobe-Nxai Pan and Okavango-Makgadikgadi migratory routes.
The Chobe-Nxai Pan zebra migration: longest mammal migration in Africa
While there has been plenty of anecdotal evidence as to the seasonal movement of various animals in Botswana, it was only in 2012 that researchers confirmed through the use of tracking collars that the zebras were completing an unexpectedly long return journey of over 1,000km each year. Up until then, the zebras’ route through inaccessible parts of Botswana, via the Kavango-Zambezi Transfrontier Conservation Area, had kept their movements largely hidden.
The herds spend the harshest of the dry months around the Chobe River flood plains from June until early November, before massing in December, when over 20,000 zebras begin their journey southwards. Most travel in an almost straight line before arriving in Nxai Pan National Park in less than a month, while others take less direct routes often stopping at Seloko Plain before joining the rest a few weeks later.
These herds disperse throughout Nxai Pan National Park (part of the greater Makgadikgadi Pan system) and remain there from December, January and February before making their return to the north. This return route to the Chobe River and north into Namibia is less direct and more circuitous, with some zebra travelling over 800km before being forced to return to more permanent water systems such as the Chobe River.
Okavango-Makgadikgadi zebra migration
Somewhat smaller than the Chobe-Nxai Pan migration, for now, this route sees the movement of around 15,000 zebras from the Okavango Delta to the Makgadikgadi Pans National Park at the beginning of the wet season, where they remain until the dry season begins.
Around March, the zebras begin to mass on the western edge of Makgadikgadi Pans National Park before setting off on their 250km return route past Maun and into the south-eastern areas of the Okavango Delta, including Moremi Game Reserve. There they remain to take advantage of the Delta flood during the dry season.
Where and when to see it?
Migrations are, by their very nature, seasonal and most are driven by the need for access to food and water. The two zebra migrations in Botswana are no different, motivated by the interplay between the wet and dry seasons, which in Botswana run from around November to March and April to October respectively. During the wet season, both groups of zebra centre around the greater Makgadikgadi Pan system, which is dry, dusty and inhospitable for most of the year until the brief months during the rainy season when it transforms into a lush green wildlife haven.
One significant benefit to viewing both zebra migrations is that they are most dramatic during the low tourism season in Botswana, meaning lower lodge rates and fewer safari vehicles. That said, the rainy season can make driving difficult if not occasionally impossible. January to April are the best months to experience the migration in the Makgadikgadi Pans and Nxai Pan national parks. In particular, the Boteti River on the western edge of Makgadikgadi Pans National Park provides one of the only permanent water sources in the area for thirsty zebras upon their return.
The future
Once, mass large mammal migrations occurred throughout southern Africa on a tremendous scale, including the migration of an estimated half a million wildebeest through Botswana’s Central Kalahari Game Reserve. These migrations have all but been eradicated, mainly due to the erection of cattle / veterinary fences blocking the original routes. The revival of the zebra migrations in Botswana has led researchers and conservationists to hope that ancestral migratory routes could be recovered if given the opportunity, not just in Botswana but throughout the world.
It does not require a leap of logic to understand that migrations can allow large mammal numbers to increase beyond what they might if they were resident in an area by ensuring that resources are not over-utilized (by over-grazing for example). It is too soon to tell what impact these zebra migrations will have on zebra numbers, but for those fortunate enough to witness them moving en-mass, there is no choice but to marvel at nature’s sheer genetic determination and resilience..