Meal in Motion

Sharks feast off the east coast of South Africa, where millions-thick sardine shoals make their phenomenal northern migration of more than 600 miles (960 kilometers). Stricter fishing regulations in recent years have boosted sardine numbers, a boon to the sharks—themselves a target of commercial fishing—and to the country's once ailing sardine industry. Fishermen today net some 220,000 tons (200,000 metric tons) a year.