The Sardine Run, one of the world's largest migrations, draws thousands of predators off the coast of South Africa. | National Geographic

Every year, predators converge off the coast of South Africa to feast on massive schools of sardines. | National Geographic

South Africa's annual sardine run is one of the planet's biggest migrations, with billions of fish heading north to Mozambique. But the greatest shoal on Earth is under threat from the climate crisis: https://cnn.it/2J8mSh1 #CallToEarth | CNN