Every year large shoals of sardines enter the waters of southern KwaZulu-Natal during the winter months. Here’s a taste of what happens when they arrive.
Every year, in June or July along the KwaZulu-Natal coast, word gets out and within hours crowds of people converge on the area to join sharks, game fish, marine mammals and birds in a feeding frenzy. It is a time of plenty for all as large shoals of sardines move in a band up the coast.
The sight of wheeling gannets folding their wings to plummet into the water around schools of dolphins surging after a boiling mass of panic-stricken sardines is an extraordinary spectacle.
So too is the equally frenzied behavior of man when massive shoals of sardines are pushed ashore.
Particular wind and current conditions may force the sardines very close to the beach, where they are easily caught using baskets, hand nets or even skirts! In fact, when sardines are beaching anything goes, and it is not uncommon to see grandmothers competing with teenagers for their share of the feast in a social occasion that draws crowds into the surf and even larger crowds of awed and amused spectators.
But why do the sardines travel up the coast?
Although the bulk of South Africa’s sardines are found in the cooler Cape waters, each winter a small proportion of the fish moves eastwards up the Wild Coast. These shoals take advantage of cool water on the continental shelf of the east coast that occurs seasonally as a narrow band between the coast and the warm, southward flowing Agulhas Current.
It is not clear what advantage the sardines gain by entering KwaZulu-Natal waters. In fact, local waters are less food-rich than the Cape waters. The favorable cooler conditions are only temporary and, to complicate matters the sardines are accompanied by many predators which prey on them mercilessly. Because the fish become concentrated near the surface in a narrow inshore band of water, the shoals are quickly located by schools of marauding predators that are whipped into a frenzy by this brief period of plenty in these otherwise less productive waters.
Nearly a quarter of the world’s fish
Although these fish are small, collectively they comprise nearly a quarter of the world’s fish catch by weight, making them one of our most valuable groups of fish.
The Sardine Run and the KZN Sharks Board (KZNSB)
The melee of predators accompanying the sardine shoals is problematic, not just to the sardines, but also to the KZNSB. The shark nets that provide bather protection along the beaches take a heavy toll of sharks and dolphins if they are not lifted before the arrival of the Sardine Run. In addition, damage to the nets themselves carries a heavy financial cost to the KZNSB. The organization’s ability to monitor the movements of the run has improved over the years. Although it has long been Board practice to lift the nets prior to the arrival of the shoals, the organisation’s capacity to monitor the movements of the shoals has improved over the years. This capacity was significantly enhanced by the acquisition of an aircraft, enabling the Board to conduct regular sardine monitoring flights.
This dramatic reduction in catches has been achieved not only by improved monitoring but also by removing the nets slightly earlier than was previously the case and by keeping them out of the water until all indications suggest that the Sardine Run is over. However, this temporary removal of the nets has implications for the tourist industry. The KwaZulu-Natal coast enjoys some of its best weather at this time of year and the Sardine Run coincides with the winter school holidays. Pressure to return the nets to the water prematurely has been eased by the introduction of “discretionary bathing”.