Cage diving boats still operate out of Gansbaai (pronounced KHANS-buy), two hours along the coast from Cape Town, and they still regularly encounter sharks. But there has been a big change in recent years. This is no longer the great white shark capital of the world. What happened?
We'll head out to famous Shark Alley, the narrow channel between Dyer Island and Geyser Island, to see for ourselves. The huge colonies of penguins and Cape fur seals which provided rich pickings for the great whites remain here, but the big sharks have gone. Other species now take their place, especially bronze whaler sharks (once extremely elusive) and broadnose sevengill sharks. With luck, we'll also spot whales and dolphins.
It's brought a dramatic shift for the shark diving companies. Great whites have long been the top-of-the-bill species. In their absence, some companies have been forced to close while others shifted their focus to the Marine Big Five: seabirds, penguins, seals, dolphins and whales.
One company still offering cage diving with sharks is Marine Dynamics, based out of Great White House in Kleinbaai, a suburb of Gansbaai. It operates tours aboard Slashfin, a custom-designed boat that accommodates up to 40 passengers. The diving cage is mounted on the side. In contrast to the early shark diving cages which completely shut in divers for the duration, you have the option to climb in and out, even when the sharks are circling.
As with any marine activity, tours are dependent on conditions and time of year. The boat won't go out if the sea is too rough or water visibility is bad, so ideally you should allow yourself a window of three or four days to provide flexibility if your chosen day isn't viable. Prime viewing occurs between June and September when the greatest numbers of sharks appear.
So out we go to Shark Alley, just a short voyage off shore. The noise and odor of the seal and penguin colonies envelop us as the boat rides the currents between the two islands. Once in position, the crew laces the water with bait to lure the sharks. Poised in our provided wetsuits, we wait for the first sighting. It may be a shadow beneath the waves or perhaps that most thrilling of sights: a fin slicing the surface.
No snorkels or scuba equipment are required, just goggles. We clamber down into the cage, and bob there with our heads above the water until the sharks swim close. Under we go, for as long as we can hold our breath.
They may not be great whites, but bronze whaler sharks still stir within us that deep, primal dread. Bronze whalers are large, powerful, lethal creatures in their own right; and when they glide toward the cage, we feel our hearts pounding in our temples. They may not have the iconic bulk of a great white, the original Jaws, but they still represent mortal danger.
But what of the great whites? Where have they gone? The decline in numbers happened rapidly. Sightings were common for decades, but within just a few seasons they fell to zero. Initially it was a mystery. Had they been wiped out by disease or overfishing? Did climate change have something to do with it?
Researchers eventually uncovered the truth. The great whites had become the target of the only marine predator that outranks them, the killer whale. For a killer whale, the liver of a great white shark has high nutritional value, and usually it's the only part of the shark they consume. When great whites started washing up on shore minus their livers, the culprit was obvious. Frightened away by their mortal enemy, the great whites fled east along the coast. As numbers plummeted in Gansbaai, they rose dramatically off KwaZulu-Natal.
Will the great whites return? Quite possibly. It may be part of a cycle. If the threat from killer whales reduces, the abundance of easy food will probably prove too much for the great whites to resist, and boat operators may enjoy another tourism boom thanks to their star attraction. But even in the absence of the great whites, shark diving off Gansbaai remains worthy of your bucket list.