Chumming is often misunderstood and is one of the key topics of contention when it comes to the shark cage diving industry.
Ever since the first settlers started calling Gansbaai home in 1811, it has been renowned for being a Great White Shark hotspot, a whole 181 years before the cage diving industry was even conceived.
Gansbaai’s popularity with Great White Sharks is due to the 60 000 Cape Fur Seals breeding on Geyser Rock, which lies 8km off shore.
Shark Alley, a 150m wide channel that runs between Geyser Rock and Dyer Island, has the perfect topography to allow for the ambush-style hunting tactic sharks use to hunt seals.
Great White Sharks are very successful predators and it is in part thanks to their perfect camouflage. Their grey topside allows them to blend into the background of the ocean floor and seals swimming at the surface looking down, won’t see them.
Great White Sharks have a perpetual presence in the waters surrounding Shark Alley, but in order for us to view them, we need them to come up to the surface.
We do this by scenting the water with fish chum. The shark’s impressive olfactory senses pick up this scent and brings the shark up to the surface where we are able to view it.
Scenting does not lure sharks to the area, but only intrigue the sharks already in the vicinity of the boat.
First and foremost, it is important to note that chum is not food, it is simply the smell of food that attracts white sharks to our boat. Imagine if you please, an oily, fishy perfume slick that floats on the surface, creating a smell trail for the sharks to follow – this is chum. Sharks are very cautious animals and without the smell of food they are not likely to come close enough to our boat for anyone to see. With the aid of chum, we are able to bring white sharks, which are already in the area, up to the surface layers of the ocean and close enough to the boat where divers can see them from the safety of our cage. Without the smell of chum white sharks would more than likely not pay any attention to the shark cage diving boats operating in Gansbaai.
Another important fact to note is that great white sharks are nomadic creatures and are continuously on the move, travelling long distances throughout their lives. Gansbaai does not have a resident population of great white sharks, but rather a dynamic flux of sharks continuously moving through the area. Current research being conducted here in Gansbaai suggests that the great white sharks spend less than 1% of their time in the vicinity of shark cage diving boats. If sharks were as motivated by chum as people believe, we would have a much easier time finding them and keeping them around our boats (which is certainly not the case). As soon as the shark’s curiosity has been satisfied and it realises there is no food, it swiftly loses interest and moves off. The sharks in this area come and go as they please with or without the presence of chum in the water. Proof of this is the fact that on some days, regardless of chumming, no sharks will pitch-up.
Having worked in this area for quite some time, it is our opinion that the low number of shark incidents, is a testament to their intelligence as great white sharks are inshore predators and share waters common to bathers and divers on a daily basis. There is a popular surf spot, less than 1km West from where we anchor and there has not been a recorded shark attack. To the East we have a popular holiday resort where beachgoers flock in the surf during the summer holidays, sometimes obliviously swimming just meters from Great White Sharks. These sharks’ survival hinges on the fact that they are cautious, incredibly elusive and selective hunters. It is easy to put the blame of a few accidents on shark cage diving. However, overfishing of some of their natural prey and our ever-increasing presence in their natural environment are additional factors, albeit inconvenient ones, that may need to be considered.