SARDINE RUN ARTICLE

Published in Submerge Magazine June/July 2007. Writer Adam Cruise

THE GREATEST SHOAL ON EARTH

It's an early winter morning on the glassy Indian Ocean, the sun low on the horizon illuminating the plunging cliffs a mile to the west. The clear sky belies the previous day's blustery weather. Everywhere Cape Gannets and the odd albatross glide by, patiently, almost languidly with no fixed direction as if waiting for something. In the distance a Humpback Whale puffs an audible whispy, white spout into the air as it continues it's epic migration northwards. To the south, barely visible, the mirrored surface breaks into a series of dark ripples. A form breaks the surface, then another and another. “Dolphins!” comes the cry from the skipper. It’s a pod of a thousand-strong moving purposefully toward us. The Dive Master directs us to don snorkeling gear and we slip into the ocean taking care not to splash. At this level, eyes in masks above the water, all one can see are the arched backs of the dolphins but dropping the mask underwater the blue realm reveals a breathtaking scene as the collective gasp from half a dozen snorkels testifies. As far down and as far across, the actual size of the pod is apparent. The dolphins have congregated in colossal numbers, all moving together and transfixed on an invisible highway toward their common goal. Hardly a dolphin affords us the slightest glance as they continue on with their constant clicking and swizzling. Here and there almost interspersed with the pod are the dark unmistakable shapes of sharks. They too show scant interest in the snorkelers. The sharks are far more intent on keeping their course on the periphery of the dolphins. They are neither part nor apart from the dolphin pod, a separate species tolerated in their marginality but not accepted into the fold. In minutes the entourage is gone leaving us snorkelers feeling alone and vulnerable in a blue void. Back on the boat, the atmosphere has changed. The gannets now are whirling above in excited circles, screeching and jostling a few hundred metres ahead. The dolphins now have split into platoons and have spread out. Something is about to give and our boat moves cautiously closer. Suddenly as if responding to a silent starter-gun the gannets tuck in their wings and begin to plummet from the sky by the dozen, plunging into the water like rockets. The water boils with activity. Our scuba gear is on hastily and over we go. Underwater the blue backdrop has been replaced with millions of tiny silver sardines swirling and zig-zagging like a giant tornado. The shoal is so big and so tightly knit that we can actually hear the sound of their scales scrapping against each other. It sounds and feels like the water is fizzing. All around, controlling and corralling the sardines in an ever-tightening ball, are the dolphins working to a prepared and structured plan pushing the sardines right up to the surface where they are pelted by a hail of birds from the air. The sharks too, satisfied with leg-work done by the dolphins, join in the melee. It's a free for all. Dolphin, shark, gannet, sardine become one confused mass and we humans need be vigilant.  My mind races to the Dive Master's briefing -  "keep arms folded, stick together, remain below the bait ball, you don't what a hand or a foot to go the way of the hapless sardines". A shark whizzes past me, sardines oozing out its jaws, the gannets sound like gunshots as they hit the water. One comes whistling down past me at six metres! And what is that? A seal! Our eyes barely have time to take in the frantic pace, everywhere there is action. The sardines are devoured from every direction over and over again until at last there is nothing left but a blue background decorated by a cascading scatter of silver glitter. It's the only thing left of the giant shoal of sardines, their scales.

There is absolutely no doubt that the annual Sardine Run is the greatest wildlife spectacle in the world. Even the wildebeest migration pales in comparison. But to most South Africans the Sardine Run is just phenomenon where manic hordes of sardine fever-gripped humans scoop up bucketloads of fish in the shallows off the beaches of KwaZulu-Natal. In truth though, these scenes of frantic human frenzy off the populated resorts of the south coast are merely the tail-end of the Sardine Run, a side-show of the main event. The real action takes place off the steep cliffs of the Wild Coast just to the north of Port St. Johns.

Normally, the humble little sardine (Sardinops sagax) enjoys cool, temperate waters between 12 and 20 degrees centigrade and for ten months of the year they inhabit the coastal shelf off the southern and western coast of southern Africa where cold upwellings bring abundant phyto- and zooplankton for the sardines to feed on. But every June and July the distribution changes dramatically when the cold southern water, pushed by successive climatic fronts, slides up the eastern coast of the country bringing with it millions of tons of sardines in its wake. The phenomenon is nothing more than a  cold-water intrusion up the east coast and not a spawning or feeding migration as previously thought. This explains the irregularity of the "run" every year. Some years the water is too warm and therefore no sardines appear north of Port Edward while other years, depending on the strength of fronts and current reversals, sardines are pushed further than normal sometimes as far as Durban. The most predominant sightings for sardine run is always off Waterfall Bluff, just north of Port St. Johns on one of the remotest stretches of our coast. Here the continental shelf narrows and rises steeply bringing in the cool water heavy with sardines upwards toward the surface where hungry predators like the dolphins can herd them into the famous giant bait-balls. This remote piece of coastline provides the most constant farthest point of the run and also influences the greatest concentration of sardines.

The big concern for anyone wanting to witness this spectacle, is that it remains a bit of a hit-and-miss opportunity. Often days and weeks go by without sighting a single sardine. Either the water is too warm or the sardines are too deep or the seas are too rough. Yet while the sardines themselves may fail to make an entrance, the show with all the other cast members goes on. Like the humans, dolphins, sharks, Cape Gannets, albatrosses, the odd seal, Bryde's Whales, penguins and even Orcas are hanging around in eager anticipation - like a public gathering in the foyer before the show. Besides, there is another marine show being played out all the while. This show, admittedly with a slightly smaller number of cast, tends to make much more of a splash. The Humpback Whale's annual migration coincides with the Sardine Run and as far as scientists can tell the two occur co-incidently and mutually exclusive from one another. The Humpbacks begin their migration in their summer home off Antarctica and travel over 16000 kilometres to their breeding and mating grounds between the southern coasts of Mozambique and northern Madagascar. This is the longest mammal migration on earth and the whales use the same cool counter-current as the sardines to assist them northbound. In the month of June and July around five thousand whales will pass by Waterfall Bluff. The Humpbacks are curious creatures and are often seen swimming up to the boats, the snorkellers, divers and even the sardines themselves to take a curious look. The best thing about the whales is that they have a lot more stage confidence than the sardines. Sitting on a boat out at sea it becomes a common sight to see the whales breach completely out of the water. On one occasion a boat load of lucky onlookers enjoyed the same whale breach eighteen times in as many minutes then sidle up to the boat for the perfect photo op then rolled over to expose his white stomach to the ogling onlookers. The whales can become so mesmerizing that for most of us there is often a tendency to forget about the sardines completely. It's a spectacular curtain raiser that threatens to become the main event.

But hard pressed as it may be, when the main event does kick off, it is unbeatable. Everywhere there are pods of dolphins, the most abundant being the Common Dolphin (Delphinus delphis) although there are sizable groups of resident Bottlenose Dolphins (Turisops truncatus) but they tend to be slower and not as agile. The Common Dolphins, on the other hand, are the most important predators of the sardine run. Marine Biologist Thomas Pechak states that Common Dolphins are the most critical reason in shaping the form and movement of the sardines. Some twenty thousand Common Dolphins move northwards with the sardines from the Southern Cape. Hunting in such large numbers and with the intelligence and speed to drive the sardines to the surface and concentrate them in bait-balls. This allows the sardines to become available to all the other predators too. One of the main beneficiaries of the Common Dolphin’s hunting prowess is the shark. The most numerous by far is the Bronze Whaler or Copper Shark (Carcharhinus bracyurus) but there are others - Dusky's, Hammerheads, Tigers and even Great Whites. The shark's lack of group intelligence and individual agility to create bait-balls means they need to rely on the dolphins to set up the dinner table for them and explains why the dolphin pods are always shadowed by these sharks. It also explains why at any given point in the ocean around Waterfall Bluff, divers are almost always joined by Bronze Whalers even when there are no sardines about. They appear like ghosts out of the gloomy depths in the hope that we, like the dolphins, are about to start hunting down sardines and they, like stray dogs, will get to share in the spoils. As with the sharks, the Cape Gannets (Morus capensis) also rely on the dolphins, following them up from the south and patiently gliding hither and thither waiting for the bait-ball to be herded to the surface before they can dive in. The gannets, in turn, assist us humans in our endeavour to see the bait-ball. The tell-tale signs of Gannets massing and swirling over a small concentrated area reveal that the dolphins have attacked and no time is wasted in getting to the bait-ball. As a rule the larger the flock of birds concentrating over an area, the bigger and longer the bait-ball will remain. This is then gets backed up by the number of dolphins in the water when the boat draws nearer. The gannets are a spectacle unto themselves when a bait-ball is formed. They literally rain down on the sardines in their hundreds like averian javelins. Underwater they leave criss-crossing irridecent bubble trails metres long underwater. Some divers wear bicycle helmets in fear of one of these birds slicing the surface of the water at over one hundred kilometers an hour onto their heads. Cape Fur Seals (Arctocephalus pusillus) and African Penguins (Spheniscus demersus) move up from Algoa Bay, but although they can hunt as effectively as the dolphins they are unable to arrive in the substantial numbers to do the work themselves. Seals and penguins lack the long-distance stamina and speed of Common Dolphins. Bryde's (pronounced Brooda) Whales (Balaenotera edeni) are one of the few year-round residents of the Wild Coast. This whale is possibly the most efficient sardine terminator of all. They dive when the bait-ball is formed then silently rush from the deep and literally swallow the entire ball of sardines with one gulp! As a diver it’s a huge jolt to the senses to see and feel this animal, the size of a bus, rush past you in a giant stream of bubbles and launch clear out of the water with over half the bait-ball in its cavenous mouth. It when they come crashing down does one realize how puny and insignificant humans can be.

In this whole melee, the humans are for once the only non-predators. Most of the visitors are scuba divers from abroad. Having watched the spectacle on Blue Planet and channels like Discovery and National Geographic, overseas divers are flocking to the Wild Coast to spend some time with the sardines and enjoy some of our country's most spectacular coastal scenery. Waterfall Bluff in particular is a sheer cliff many kilometres long with hanging green fields and plunging waterfalls that meet their zenith in the sea. The secluded beaches are dotted with herds of Nguni cattle - bovine-beachcombers against a backdrop of scattered Xhosa huts. This is quint-essential rural Africa, an idyllic Eden that has not been spoilt since the dawn of time. Initially, these are the reasons that made the logistics of hosting top-dollar tourists a bit tricky since there is precious little infrastructure. No real development, no major town or international airports, few shops and tar roads can make operating the show extremely challenging. The hit-and-miss scenario of the bait-balls was also a concern as it is generally impossible to predict the timing and movement of the "run". However, these days the logistics have been expertly arranged by a select group of tour and dive operators alike and in conjunction with local accommodation facilities have had the benefit of half a dozen years of practice of hosting international film crews. These days they are more than equipped to put on the show. Microlights go airborne at the break of dawn to spot the shoal's movements and re-direct boats to the area. Boats are big and comfortable and provide food and beverages on board. The skippers are experienced and knowlegeable as are the Divemasters, both pride themselves with strict safety measures while at the same time ensuring their guests get the moment they will never forget. The best part of all is the fact that humans can get right up close and almost be apart of this frenetic wildlife spectacle. It’s like running with a pride of lions when they hunt down a wildebeest, then lying next to them while they devour it! South Africans too are slowly waking up to the fact that the Sardine Run is much more than the crazed beachings of sardines and are now beginning to enjoy the fact that every year South Africa plays host to the Greatest Shoal on Earth.

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