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WonderMarine migration fact

The sardine run takes place off South Africa's east coast from about May to July, when vast shoals of sardines follow a band of cool water north along the shore. Dolphins, gannets, sharks, seals and whales gather to feed on them.

KwaZulu-Natal sardine run

MigrationOceanBiologyClimateScience

The story behind the card

Sardines normally live in the cooler waters off South Africa's southern and western coasts. In some winters a narrow strip of cold water forms close to the shore of the Eastern Cape and KwaZulu-Natal, between the coast and the warm Agulhas Current, and the fish move north along it. The shoals can stretch for several kilometres and are followed from the air by spotter planes. Common dolphins herd the sardines into tight balls near the surface, Cape gannets plunge in from height, and sharks, Cape fur seals and Bryde's whales feed on the exposed fish. Scientists are still not sure what sets the run off: in some years it is weak or barely happens, and why is not fully understood.

Türkçe oku
Sardalya göçü her yıl kabaca mayıs ile temmuz arasında Güney Afrika'nın doğu kıyısında yaşanır: dev sardalya sürüleri, kıyı boyunca uzanan serin bir su şeridini izleyerek kuzeye ilerler. Yunuslar, sümsük kuşları, köpek balıkları, foklar ve balinalar bu sürülerle beslenmek için toplanır.

Sardalyalar normalde Güney Afrika'nın güney ve batı kıyılarındaki serin sularda yaşar. Bazı kışlar Doğu Kap ile KwaZulu-Natal kıyısında, sahil ile ılık Agulhas Akıntısı arasında dar bir soğuk su şeridi oluşur ve balıklar bu şerit boyunca kuzeye ilerler. Kilometrelerce uzayabilen sürüler havadan gözcü uçaklarıyla izlenir. Yunuslar sardalyaları yüzeye yakın sıkı yumaklar hâlinde toplar, sümsük kuşları yüksekten suya dalar; köpek balıkları, Kap kürklü fokları ve Bryde balinaları da açıkta kalan balıklarla beslenir. Göçü her yıl neyin başlattığı hâlâ tam bilinmiyor: bazı yıllar zayıf geçiyor ya da neredeyse hiç yaşanmıyor, bunun nedeni de henüz tam açıklanamadı.

Sources and further reading

Background reading: Sardine run
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