South Africa's great white sharks mysteriously disappear. Scientists are unable to agree on who or what is to blame.

when the great white shark debuted extinction from coastal waters Around Cape Town, South Africa, some scientists and conservationists were astonished.

When 60 Minutes correspondent Anderson Cooper visited, the waters were filled with great white sharks diving with hunters in 2010. The area was home to small sharks and seals, which were hunted by great whites, turning it into a hotspot.

But just a few years later, the sharks began disappearing, confounding scientists and conservationists. South Africa was the first country in the world to protect the great white shark in 1991, but today, some are concerned that it will be the first country to lose this population due to local extinction.

Photographer Chris FollowsThe man who captured some of the most iconic photographs of great white sharks said he used to see 250 to 300 great whites there per year, but now there are none. The mystery of why they disappeared has fueled a bitter feud between scientists and conservationists, who can't agree on who the real culprit is.

He said, “Let's stop arguing about what we can't control, and let's start focusing on the things we can control.” “If we don't start addressing the factors that we can control, then I don't think there's any hope.”

when the sharks disappeared

Alison Cock, a marine biologist with South African National Parks, found the first clue in 2015. Divers sent him photos of small shark carcasses with mysterious incisions on the ocean floor.

“It looked so surgical in the pictures that I first assumed someone must have done it with a knife,” Cock said.

Cock and his colleagues went diving for more evidence and encountered an unlikely suspect in the water: orcas, also known as killer whales. She describes it as a “light bulb” moment. Two orcas went under their boat in the same area where they found a shark carcass.

“What we now have is that orcas are a real possibility to blame for these carcasses,” Kok said. “I feel like a detective. But for a long time, we didn't have all the pieces of the puzzle.”

Two years later, carcasses of great white sharks began washing up on shore with the same incision marks. Kok and his colleagues conducted an autopsy and confirmed orcas eating great whitesEating their livers.

“It's the most calorific organ in the entire body. And it takes up about a third of the shark's body,” he said.

Orcas have lived in South African waters for years, although no one had ever seen one kill a great white in the region. Still, there were whales Known to hunt sharks Off the coast of California and around Australia.

Great white sharks were seen as apex predators, so many people struggled to see them as prey for orcas. But orcas are smart hunters and “are learning all the time,” Kok said.

port and starboard

Whale watching tour operator David Hurwitz was the first person to witness two distinct male orcas hunting and killing a shark. He named them Port and Starboard.

“They become world famous or infamous,” Hurwitz said. Notorious because unlike most orcas which hunt in groups called pods, Port and Starboard were hunting sharks for their livers as a pair.

Scientists now believe that Port and Starboard may also be teaching other orcas how to hunt sharks. In 2022, drone footage captured five orcas working together, stunning and then killing a great white. More recently, single orcas have been observed hunting sharks in South Africa and elsewhere.

The big white men, who were unaccustomed to being hunted, fled to the shore, Coke said. They believe that the overall population of great whites in South African waters is stable.

Others say it's humans' fault, not the whales'

Not everyone believes the case has been solved. Marine biologist Enrico Gennari, who has been researching great white sharks in South Africa for 20 years, says the great white shark population is in decline. He places the blame on the other culprit: humans.

Photographers Gennari and Fallows say that the numbers of great whites had declined a few years before Port and Starboard began the killing spree.

Together, they are documenting the impact of commercial fishing boats on the small shark species that great whites prey on. There are miles long queues of boats attached to thousands of hooks on the seabed. The sharks they catch are exported to Australia, to be used for cheap fish and chips.

“Shark longlining is undoubtedly robbing great white sharks of their food,” Fallows said. “This is the primary prey source for great whites when they are not eating seals.”

The pair say shark nets and baited hooks attached to buoys, which South African authorities have used since the 1950s to protect swimmers at the coast, are also to blame. Nets and hooks kill more than 20 great whites a year.

“The device is designed to kill and reduce the population,” Gennari said. “The concept is one less shark, one less chance of an encounter with a human.”

protection of the great whites

Instead of nets and hooks, Gennari would like to see South Africa adopt a variety of options to protect swimmers, such as underwater magnetic fields that hinder sharks' access to prey. They also suggested increasing the use of small mesh nets, which create a barrier without entangling marine life. The methods used now, which are lethal to sharks, are “outdated and unsustainable,” he said.

“If we lose the white shark in South Africa, we lose the battle for all of nature,” Gennari said. “If we can't protect even the most charismatic, most protected species on paper in South Africa, what chance do the little guys, other sharks or other animals have against unsustainable use? Nothing.”

Fallows hailed the return of humpback whales to South African waters as a conservation success story that can be emulated. The population rebounded after a moratorium on commercial whaling was implemented in the 1980s.

He said, “I believe 100 percent of it has to do with enlightened governments, passionate individuals, showing whales for what they are: incredibly sentient creatures that have a vital role to play in our ocean.” “It's called balance. A balanced ocean is a healthy ocean. A healthy ocean is a healthy environment for us.”