A winter holiday on the South Coast can be even more rewarding than a summer one. The water may not be warm enough for swimming, but it is cold enough for sardines – billions of them!
Shoals of Southern African pilchard (Sardinops sagax) – or ‘sardines’ – move northwards along the east coast of South Africa, bringing thousands of predators in their wake.
The ‘sardine run’, first recorded in the Natal Mercury newspaper of 4 August 1853, occurs when a current of cold water heads north from the Agulhas Bank up to Mozambique, where it leaves the coastline and goes further east into the Indian Ocean.
The shoals are often more than 7km long, 1.5km wide and 30 metres deep and are clearly visible from aircraft or from boats and the land. Banding together in vast shoals is an instinctive defence mechanism, as solitary fish are more likely to be eaten than those in large groups.
The sardines migrate from the Atlantic coast, via the temporarily cold water area off the south-east coast and are forced northwards to escape the seasonal warming of the water.
The strong, warm offshore Agulhas Current, which flows in the opposite direction to the migration, creates a band of cooler coastal water, enabling sardines, which prefer water temperatures between 14 and 20°C, to survive.
Thousands of common dolphins (Delphinus capensis) are largely responsible for rounding up the sardines into bait balls. These bait balls can be 10–20 metres in diameter and extend to a depth of 10 metres. Once the sardines are rounded up, sharks and birds take advantage of the opportunity and a feeding frenzy ensues. The Cape gannet is the predator species that is is the most useful indicator of the presence of sardines. The resident bottlenose dolphins do not appear to associate with the sardine run, whereas the visiting common dolphins do. Other marine predators including Cape fur seals, sharks, whales and game fish. making the sardine run a truly spectacular event – and the South Coast offers visitors to the area front-row seats.
There are many ways to experience the phenomenon, from land, sea and sky. There are charter boats that will take guests out for a close-up experience, including watching from the boat, snorkelling, scuba diving or deep-sea fishing. You can see a lot of the sardine run action from one of the whale decks along the coast. These include Umtentweni Conservancy Whale Deck, Ramsgate Whale Deck, Impithi Beach Kiosk and Umdoni Golf Club Whale Deck.
But by far the best place to enjoy the excitement is on the beach – if you are lucky enough to be on the right beach at the right time. Within hours, crowds of people join the other predators to claim their share of the sardine harvest. Although the individual fish are small, collectively they comprise nearly a quarter of the world’s fish catch by weight, making them one of the planet’s most valuable groups of fish.
Because the fish become concentrated near the surface in a narrow inshore band of water, the shoals are quickly located by predators. As the shoals are driven to the surface, birds – Cape gannets, cormorants, terns and gulls – plummet out of the sky to grab their share and sometimes consume so much that they have to rest on the surface for some time, being unable to become airborne!
T’he progress of the sardine run is closely monitored by anglers, who flock to the beaches and rocks to participate in excellent game-fishing. Commercial fishing of the sardines themselves is also undertaken using beach seine nets, which are pulled from the shore. While one group of fishers holds a rope at one end of the net, the other end is cast around the shoal of fish using a small boat. The encircled fish are then dragged ashore, where they are quickly scooped into baskets both by the fishers and many eager helpers.
Particular wind and current conditions may force the sardines very close to the beach, where they are easily caught using baskets, hand nets, supermarket carrier bags or anything that comes to hand. Young boys are frequently seen, stripped to the waist, using their t-shirts to catch the fish and carry them home in triumph.
The excitement is infectious and a carnival atmosphere is felt on the beach. Willing hands help the seine netters – and each other. There’s plenty for everyone. One elderly pensioner arrived home dripping wet – with one small sardine. He had lost his balance in the shallows before he could net a single fish, but a little boy of about five years old, had felt sorry for him and given him a sardine so he wouldn’t go home empty-handed. Such is the camaraderie engendered by a shoal of little silver fish!
Sources
Wikipedia
shark.co.za/sardine-run/