The southern African sardine run happens from May through July when literally billions of sardines spawn in the waters of the Agulhas Bank and travel northward along the east coast of South Africa. It is the most enormous predatory hunt in the world with their awesome numbers creating a feeding fury along the coastline and photographer Jason Heller was there to snap these shots.
The run contains millions of individual sardines and the phenomena happens when a current of chilly water moves north from the Agulhas Bank travelling up to Mozambique. From there it then leaves the coastline and moves farther east into the Indian Ocean.
As far as biomass is concerned studies approximate the sardine run could equal East Africa’s great wildebeest migration, but not much is known of the event. What is known is that the water temperature needs to dip below 21 °C to trigger the migration. Bryde’s whales, sharks, in addition to dolphins all come in droves for the fish. Dolphins, as unbelievably social and bright creatures will toil as a group to drive the sardines to the surface, while the whales and the sharks mooch off their work.
Sadly, ocean warming is a crisis that might bring an end to this magnificent event. In 2003, the sardines did not do the run, a third time for this to happen in 23 years. 2005 was an excellent run, while 2006 once again resulted in another non-run. Also, during the 2009 winter, an unrelenting record high water temperature of nearly 22 Celsius was recorded during a 20 day period, a temperature much too warm for the sardines.
Furthermore, the global fishing industry does not add any help to this diminishing phenomenon. The shoals are usually measure more than 7 km long, 1.5 km wide and 30 meters deep and are quite observable from spotter planes or from the ocean surface.
See images of the magnificent sardine run here.