Sardine Run

Each winter a cold current pushes north along the east coast and vast shoals of sardines move with it from the Agulhas Bank towards KwaZulu-Natal, in a migration often compared to the Serengeti wildebeest for sheer biomass. What draws people is not the fish but the pursuit: common dolphins herd sardines into bait balls, sharks and game fish work them from below, Cape gannets dive into them from height in continuous streams, and Bryde's whales come up through the middle with mouths open. Operators run boats and divers out of Port St Johns and the KZN south coast through June and July. The honest part is unpredictability - the run varies enormously year to year, some seasons barely happen, weather cancels days at sea, and finding action means hours of searching with a spotter plane. Sometimes shoals reach the beaches and people scoop them up in buckets.

What you'll find

• The bait balls - dolphins herding sardines into spheres worked by everything else.
• The gannet dives - continuous streams of birds hitting the water from height.
• The whales - Bryde's whales lunging up through the shoals.
• The variability - a run that fails or shifts entirely in some years.

When to go

June and July. Several days, because weather and the run itself are unreliable.

Before you go

Some years the run barely materialises and charters find little. Sea conditions cancel days at a time and the boats are small and rough. Diving is for confident open-water divers - conditions are cold, deep and busy with sharks. It is expensive for a chance, not a certainty.

Nearby

Port St Johns is the Wild Coast base; Aliwal Shoal is further up the KZN coast.