The Greatest Shoal on EarthBy
Every year during the winter months of June and July in South Africa, one of natures greatest events take place. Millions of little sardines abandon their spawning waters of the Agulhas Bank located in the southern waters of South Africa where the cold Atlantic Ocean and warm Indian Ocean meet. It is the coming together of these two oceans that make the waters ideal spawning grounds as they are rich in nutrients.
The exact reasons why the sardine migrate away from such nutrient rich waters aren’t known but they thrive in water temperatures of around 20 Celsius. As the winter waters of the Eastern Cape and KwaZulu Natal cool, it is believed the sardines take advantage of their expanding territory and head northwards up the South Africa coast.
Measuring up to around 9 inches in length, these little fish travel in massive shoals clearly visible from the surface of the ocean. The shoals can be several kilometres long and up to a kilometre wide so in terms on numbers, they easily rival Africa’s other famous migration of the wildebeest as they head north from the Serengeti into the Masai Mara.
The Sardine Run is a big event of the Eastern Cape and KwaZulu Natal. As sardines are pretty much at the bottom of the food chain, it isn’t much of a surprise that when they create shoals more than a million strong that predators are soon on their trail. Under the water, the shoals of sardine are mercilessly pursued by sharks, tuna, dolphin and even whales. As they come under attack, the little fish form defensive bait-balls but it is little protection as time and again, the predators hit the bait-balls, taking a few of the little fish with each attack. There are some many sardines and predators in the water during the Sardine Run that the Natal Shark Board remove the shark nets that usually protect the beaches to prevent the sharks, dolphins and other large sea creatures from getting caught up and dying.
As the shoals come under attack, they are forced into shallower waters where they start to come under attack from the air as the sardine come within diving depth of gannets who join in the bountiful feast that nature has provided. Humans get in on the act too. As the shoals move to try to escape the caravan of predators, they move into shallow waters small fishing boats move in the fish are literally dragged ashore by crowds of waiting people. As well as the fishing nets all sorts of containers are used to scoop up the sardines by people trying to gather as many as they can carry.
The Sardine Run is a natural event and therefore it is by no means guaranteed. There have been no shows in recent years but every winter, the Greatest Shoal on Earth is eagerly anticipated by the people who live up and down the coast of the Eastern Cape and KwaZulu Natal in South Africa.