Nature's Great Events -  The Great Tide

As winter arrives along South Africa's east coast, the inshore waters cool, drawing billions of sardines northwards. The sardine run is the world's largest spectacle, attracting the planet's greatest concentration of predators in any one time - an awe-inspiring array of ocean hunters.

Super-pods of common dolphins up to 5,000 strong, thousands of sharks and huge whales feast on the sardines, as gannets dive down from above. But in recent years, the sardine run has become less than predictable, and if the sardine run doesn't happen, the lives of animals caught up in the drama each year, hang in the balance.

As sardines are pushed into the shallows, thousands of sharks start to encircle them. The climax of the sardine run is a spectacular feeding frenzy as the dolphins round the sardines up into balls on which all the predators feast. Slow-motion filming captures every detail, while both aerial and underwater photography capture the high-octane action as the dolphins, sharks and whales compete for the abundant prey.