WHEN GOLDEN PLAINS TURN BLACK

The Serengeti’s golden plains may be home to the Big Five, but the unsung heroes of these grasslands are its white-bearded wildebeests. Each year, over a million complete a staggering 1,250-mile circuit across Kenya and Tanzania, one of the last intact wildlife migrations on Earth. By creating and maintaining the ecosystem, they are the seams holding it together, performing an ancient dance that still sweeps across the savannah

- SARAH MARSHALL

The sound of 8,000 hooves is electrifying. Funnelling down a sheer, dusty drop on the riverbank, the herd roars into the water, tearing at the soil and rupturing trees from their very roots. Locked densely together, this tangle of curled horns elegantly sinks and swirls like a group of debutantes performing a Viennese waltz. But once the first splash is made, any decorum is lost as a survival instinct kicks in. A low, thundering rumble drowns individual cries as the animals focus on one unanimous goal: to reach the other side.

We’d rushed to this point along the Mara River, in the northern Serengeti’s Kogatende area, here in Tanzania. Looking through his binoculars to judge the size of the herd amassing, my ambitious and endlessly energetic Maasai guide, Moinga, had glanced at his watch and declared: “We can make it.” Crashing across granite gullies and swerving through quagmires of sticky black cotton mud, we’d arrived right on cue.

Every summer, in relentless pursuit of new grass, wildebeests cross the watery border to Kenya, before being lured back by rains between October and November and heading hundreds of miles south to calve on the Serengeti’s southern plains. The migration is often synonymous with river crossings like this, but for most people who witness the herbivores’ annual grazing cycle, the primary spectacle to behold is that of vast golden plains painted black.