Gansbaai

Cage diving became Gansbaai's main trade in about 1995, and the town was soon routinely billed as the great white shark capital of the world. Boats run out of Kleinbaai, a small harbour minutes from Gansbaai, for the roughly 8 km crossing to Dyer Island and Geyser Rock, where operators such as Marine Dynamics work Shark Alley, the channel between the two islands, from a surface cage fed by air piped from a compressor, so no diving qualification is needed to get in. What draws sharks to the channel is Geyser Rock's Cape fur seal colony, some 60,000 animals strong; Dyer Island's penguins and bottlenose dolphins work the same water, but neither island can be landed on.

From around 2015 the picture changed. Two male orcas with distinctive collapsed dorsal fins, nicknamed Port and Starboard, began hunting white sharks along this coast, flipping them into a paralysed state and eating only the liver; carcasses started washing up with nothing else touched, and a 4.9 m female known as Khaleesi was found this way in 2017. Sightings at Gansbaai and neighbouring False Bay fell toward zero for long periods, and several operators have since closed.

Whether the sharks relocated east to Algoa Bay and KwaZulu-Natal or the population genuinely declined is disputed in the scientific literature: a 2023 study argues for stable numbers and eastward redistribution, while a 2024 rebuttal points to falling KwaZulu-Natal catch rates as evidence against a clean relocation story. Operators still running increasingly market bronze whaler (copper) sharks and broadnose sevengill cowsharks, which keep showing up in the same water, as much as the white sharks they were built around.

The activity has a real safety record worth knowing rather than guessing at. In 2005 a great white bit through the bars of a cage off this coast, and the diver was pulled out unharmed as the crew fought the shark off; in 2008 a cage boat anchored over the nearby Geldsteen reef in rising swell was capsized by a large wave, throwing all 19 aboard into the water and killing three; a 2014 court found the skipper and operators negligent for anchoring over a shallow reef in worsening conditions rather than the shark encounter itself. No diver at Gansbaai is documented as having been bitten inside an intact cage.