How the white shark mysteriously disappeared from Cape Town Bay

About 16 kilometres from the coast of the small town of Simonstown on the Cape Peninsula, lies a rocky island dotted with seals. Every piece of the island seems to be moving. There are over 60 thousand of them. This time of year is quite crowded: many seals have young, who playfully dive into the water.

For years, these seals were a tasty snack for the most famous marine head in the world: the white shark. It was one of the reasons why, large parts of the year, you were almost insured to see a white shark when you went out on a boat, says Rob Lawrence. He could know. For decades, he‘s been taking tourists on his boat to search for white sharks.

On the aft deck is a large cage that is launched as soon as they have spotted a shark so that visitors can get as close as possible to the animal. Shark diving is a big industry. But in recent years, Lawrence hasn’t seen a white shark in False Bay, the bay near Cape Town.

The lack of the white shark falls Lawrence hard:

Local shark experts from the Sharkspotters organization counted over 200 sharks a year in False Bay between 2010 and 2015. Between 2015 and 2018, it decreased to fifty white sharks a year, and in 2019 and 2020 they didn‘t see one.

In January, the investigation team saw another one. โ€œBut that is very sporadic,โ€ says Sarah Waries of Sharkspotters. โ€œAnd not comparable to 2011, when we once saw 35 at the same time in the bay.โ€

Experts are trying to figure out what happened to the white shark. Last year the government assembled a team of local and international experts. Their main conclusion was that the disappearance of the white shark is linked to the arrival of a few killer whales in the bay in 2015.

โ€œ We’re talking about two killer whales that we called Port and Starboard,โ€ says Waries. โ€œThose whales hunt together and tear open white sharks to eat their livers. We know this because we found carcasses.โ€ The experts do not think that all the white sharks were killed, but that most of them left for fear of the killer whales.

According to this theory, the white sharks have migrated. But where to go? Marine biologist Sara Andreotti from the University of Stellenbosch has been studying the white shark since 2009 and does not believe in killer whale theory. โ€œIt‘s a good story but distracts from the other reasons. Reasons for which we, as a human being, are responsible for and that the government can do something about.โ€

She has been worried about the decline in the number of white sharks in South Africa for much longer. In 2016, she published a study in which she wrote that on the South African coast there are only 353 to 522 white sharks with low genetic diversity. Much less than assumed. According to her, the Sharkspotters often count the same shark several times.

Overfishing

The biologist is afraid that the white shark has not disappeared, but that they are extinct. Andreotti mentions a variety of reasons why the white shark has been threatened for a long time on the South African coast: pollution, shark nets to protect swimmers and surfers but where sharks get stuck, sharks caught as by-catch by fishermen and above all: overfishing .

The

latter is a crucial point: the white shark is protected in South Africa, but other sharks are not and they are caught commercially. This has a direct influence on the white shark because it eats smaller sharks. There’s a chance that the white shark will be starved.

โ€œ We really need to pay more attention to this because the whole ecosystem is changing with the disappearance of the white shark. We can do a lot like putting smaller sharks on the list of protected species and placing cameras on commercial fishermen‘s boats so we know what they’re catching. If we assume that the killer whales are the reason, and we do not intervene, then we can be responsible for the extinction of the white shark.โ€

‘Not sexy enough’

Lawrence is afraid that the white shark is not sexy enough to fight for, in the same way that people take action for, for example, rhinoceros being punched. โ€œI hope every day that the white shark will come back. We keep looking for them.โ€