Shoals of shimmering sardines have been spotted making their way up the Eastern Cape coastline toward KwaZulu-Natal. The KZN Sharks Board said on Facebook that its Operations Division undertook their first sardine observation flight of the 2022 season.
The division decided to make the flight a bit earlier than usual due to the high frequency of reports regarding sardine activity along the Eastern Cape coast.
Greg Thompson, acting head of operations at the Sharks Board said “depending on the biomass of sardines, water temperatures and the inshore current conditions, we expected to see signs of sardine activity" somewhere between Mazeppa Bay and East London.”
The South African National Biodiversity Institute says that sardines are migratory species. They migrate to specialised grounds for spawning and migrate back to their usual grounds after spawning. Spawning is the process of releasing sperm and/or eggs into the water, which will later hatch into fry and carry on the cycle.
Sardine distribution in Southern Africa extends from southern Angola, off the west coast of South Africa, to the north of Durban, off the east coast of South Africa.
Video: Motshwari Mofokeng/African News Agency (ANA
An excellent indicator of large sardine shoals is the equally large numbers of predators that follow the shoals, picking off the tiny fish in a feeding frenzy. These predators include hundreds to thousands of Cape gannets, extraordinarily large pods of bottlenose and common dolphins, as well as large shivers of sharks. These are all indicators that the Operations Division staff keep an eye out for, on every recon flight.
“During the first part of the flight into the Eastern Cape, spotting was made extremely difficult due to the amount of muddy, discoloured water from the April floods, between Waterfall Bluff and Port Saint Johns.
“However, as soon as we found some cleaner water off Umngazi River Bungalows, approximately 50 small pilot shoals of sardines/baitfish were spotted in this area, through to Brazen Head,” Thompson said.
Thompson admitted that the thin pockets of fish were very difficult to identify from the air, as there were no predators in pursuit, and the pockets were so thin that they had no colour. Then again, small, thin pockets were seen shimmering on the surface off the Mthatha River and Mpame Point.
Qolora Mouth, Kei Mouth, Haga Haga, Chintsa, Gonubie, and East London saw the most concentrated activity. Thousands of Cape gannets were seen spread out, sitting on the water in rafts throughout this area, with concentrated diving in some areas. These gannets were accompanied by hundreds of common and bottlenose dolphins.
Thompson said that these are positive indications that the sardines are making their way up the Eastern Cape towards KwaZulu-Natal and are possibly just a few weeks away. Thompson cautions that there have been many occasions in the past when predictions and opinions have been totally incorrect.
The sardines could take advantage of the discoloured water along our coast and swim through, out of sight of most of the predators, and arrive in KZN without warning. There is also the possibility that they continue moving north on the deeper currents and do not come close to the shoreline at all.
Thompson said that, depending on weather conditions, the next flight to East London is scheduled for May 18. Thompson will continue to update information on sardine activity as and when flights have been completed.