The World's Largest Mammal Migration That Few Travellers Ever See Deep Inside Zambia, Millions of Bats Create One of Nature’s Greatest Spectacles Every evening, as the sun slips behind the forests of northern Zambia, the sky begins to change. At first, it looks like a distant storm cloud gathering on the horizon. Then the dark mass expands, thickening and stretching across the fading light. Within minutes, what seemed like a cloud reveals itself as something far more extraordinary: millions of bats taking flight simultaneously. The sound arrives next a rolling wave of wings beating through the air. Trees disappear beneath swirling shadows. The setting sun turns orange and purple behind a living curtain of movement. For a few weeks each year, a small wetland forest in Zambia becomes the stage for what scientists describe as the largest mammal migration on Earth. Nearly 10 million straw-coloured fruit bats converge on Kasanka National Park, creating a natural phenomenon so ...