There are a few distinct highlights to our year here at Aliwal Shoal Scuba. There’s the return of the tiger sharks at the beginning of summer, and the return of the ragged-tooth sharks with the arrival of winter. There’s the festive mania of December, and the first sighting of the humpbacks on their yearly migration past our front door. Of all these, the annual event we look forward to the most is the Sardine Run – and now, with June already well underway, it’s just around the corner.

The Journey to Port St Johns

In a few weeks’ time, we will be moving our dive boats, skippers, divemasters and equipment south to Port St Johns, a picturesque town steeped in history and known as the Jewel of the Wild Coast. There, amidst the town’s breathtaking scenery and famously friendly atmosphere, we will set up camp, ready to take part in the 2016 Sardine Run. Comparable to East Africa’s great wildebeest migration in terms of biomass, the Run is one of the planet’s most impressive natural spectacles.

Every year between the months of May and July, billions of sardines (also known as Southern African pilchards) spawn in the cool waters of the Cape’s Agulhas Bank. The sardines are a cold-water species, and can only tolerate temperatures of 21ºC or less. At the same time as the spawning, a temporary corridor of cool water opens up along the the country’s east coast, encouraging the sardines to move northwards in tight groups, or bait-balls.

Easy Pickings for Opportunistic Predators

The bait-balls are trapped by the land on one side, and the warmer Agulhas Current moving southwards along the edge of the continental shelf on the other. With nowhere to run but north, the sardines provide easy pickings for opportunistic predators, which arrive in their thousands to take advantage of the sudden bounty. Temperate species like Cape fur seals and great whites come to prey on the sardines from the south, while tropical gamefish descend on the shoals from the north.

Harbingers of the Sardine Run

The action also draws pelagic species in from deeper water, including dusky sharks and copper sharks (also commonly known as bronze whalers). With so much going on, one never knows who might turn up to the feast, and in past years we have seen Bryde’s whales, bull sharks and even a pod of orca. There are some species that are guaranteed to be in attendance however. These include Cape gannets and common dolphin, both of which are harbingers of the Sardine Run.

We use these two species to lead us to the bait-balls, which despite the chaos they cause, can often be difficult to find. Once spotted, no-one knows how long the bait-ball will last – perhaps hours, perhaps only minutes. In order to succeed on the Sardine Run, it’s necessary to spend long hours on the water. At Aliwal Shoal Scuba, we have the experience and the commitment it takes to give you the best possible chance of experiencing this phenomenon for yourself.

Dense Clouds of Panicked Fish

Those that have experienced a Sardine Run bait-ball will know what a privilege it is to witness nature on such a formidable scale firsthand. At first, chaos seems to reign. Gannets paint the ocean all around with silver slipstreams of dissipating bubbles, the sound of their entry as shocking and sudden as a gun fired at close range. The bait-ball itself is a dense cloud of panicked fish, turning the world dark as they move as one entity across the sun.

Through the seething mass, sharks and dolphin dart like lightning, somehow avoiding one another in a carefully choreographed dance. They are brief glimpses of gunmetal and cream, rather than distinct, individual forms. If you’re lucky, before the bait-ball is diminished into nothing more than a shimmer of falling scales, a Bryde’s whale will appear from the gloom, as big as a train, renting the ocean in two. With the sardines gone, it’s time to surface… and start the search all over again.

Would you like to take a Sardine Run Scuba Diving trip with us? Contact Lelanie on +27 82 800 4668 to book your place today! Only a few spots open so there is limited availability. 

Previous reading
A Diver’s Guide – Protecting The Marine Environment
Next reading
All Set For 2016 Paddle Out For Sharks