How White Sharks Became the Serial Killers of the Sea

In February 2017 a large white shark was observed attacking and kill­ing a juvenile humpback whale in Mossel Bay, South Africa. It was witnessed by the crew of the Oceans Research Institute vessel, one of whom used an aerial drone to capture live footage of the event. The humpback whale was found entangled in ropes, in a poor condition, its emaciated body covered with barnacles and lice. Soon an 11-foot-long white shark slowly approached it, and after observing it for a couple minutes, inflicted a strong bite on its left side behind the flipper.

The shark immediately let go and moved away without taking any plug of flesh to eat, just causing a severe wound. The shark then waited while the whale slowly bled for another 42 minutes before it came in and bit the whale a second time, under the tail, also immediately letting go without removing any flesh from the whale.

A second, larger shark estimated at 13 feet long then approached and attacked the whale on the tail base, and this action prompted the first shark to move away from the whale. The large shark then attacked the whale with a fourth bite, targeting the already wounded base of the tail. This was a more aggressive bite in which the shark violently shook its head and tried to push the whale under the water. By now the whale had lost a lot of blood and was very weak—it lived just another thirty minutes. One shark left the scene at this time, while the other waited around until the carcass sank to the bottom. The sharks were not sighted again at this point; presumably both were busy feeding on the carcass below.

While white sharks are well known as scavengers who will readily feast on dead baleen whales, this account was the first record of white sharks attacking and killing a living humpback whale. It showed they cooperated using a “bite and split” tactic rather than expending more energy to kill the whale quickly with many attacks. It gives us a good idea how these sharks probably operate by using measured, strategic hunting tactics rather than just charging in with brute strength. It also indicates that ancient white sharks of similar size could have brought down large baleen whales in the wild.

When they first appeared in the seas about 6 or 7 MYA, baleen whales were much more abundant in the oceans and represented more species than today. Even with mega­lodon prowling around, there would have been plenty of whale and smaller manatee prey for the first white sharks to hunt.

White sharks are known for their predatory instincts that encompass both brawn and brains. In fact, scientists have recently shown that these sharks have evolved specialized hunting behaviors. Dr. Charlie Huveneers, a shark biologist based at Flinders University in South Aus­tralia, works just a few doors down the corridor from my office. Charlie is more at home wearing a wetsuit, immersed in the blustery, foaming waters off the coast of South Australia, than sitting at his desk. He is a leading researcher on white sharks who first became interested in the subject when he was growing up in Belgium.

Charlie became inter­ested in sharks at age eleven, when he did a school presentation about them at the suggestion of his mother, who bought him a book on sharks. The editor of that book was Dr. John Stevens, a legendary shark researcher based in Australia. Charlie would later work with him, tagging sharks, and today he is head of the Southern Shark Ecology research group at Flinders University.

Charlie has spent hundreds of hours on boats and in cages underwa­ter observing, tagging, and tracking the large population of white sharks living off the Neptune Islands. His team’s research is shedding much new light on the attack behaviors of the white sharks. Just re­cently they made more than four hundred observations on how they approach and attack their prey. Surprisingly, they found from their sta­tistical analyses that white sharks always attack with the sun behind them, giving them the advantage of coming out of the light where visibility is poorest for the prey. Most shark attack victims simply don’t see the shark coming at them. The white sharks are using their innate knowledge of astronomy to develop the most successful attack strat­egy.

Research carried out by Michael Martin and colleagues from the University of Miami in 2009 showed that white sharks use stalking methods similar to those of human serial killers. The research included input from Kim Rossmo, a criminal justice expert who is a specialist in the geographical profiling of criminal acts. Rossmo uses the locations of linked crimes to predict the next location of a criminal’s “anchor point,” or the region where the next attack might be initiated.

Their study of some 340 attacks on fur seals showed that the white sharks hunted seals in areas known to be more prevalent—they were using an “anchor point” to launch attacks that would be more successful than using random places to attack. By the white sharks’ effectively develop­ing a strategy to plan an attack, they were behaving the way human serial killers do in their methodical approach to successful kills of their victims, keeping maps in their head of their underwater hunting grounds.

Another study looked at white shark vision, testing the “mistaken identity theory” that sharks attack swimmers and surfers because they see them as seals. Most attacks on surfers are from juvenile white sharks. The shape and motion analyses proved that images of humans swimming, or on surfboards being paddled or towed, could not be distinguished in the retinas of the shark from outlines of their natural prey, the seals. However, we know the sharks have a powerful sense of smell, so in many cases this may be the main sensory input that deters a shark from randomly biting a human in the water.

White sharks have amazing superpower senses of smell and electro­reception. These fishes have poor eyesight, but highly attuned noses that can detect substances in water diluted by one part in 10 billion—they can smell a plume of water tainted with blood and tissue carried on a current from at least four miles away. Their sensitive electrosen­sory organs, called ampullae of Lorenzini, appear as a myriad of tiny pore openings covering the snout and side of the head.

These are the openings for flask-shaped cells, each containing a network of delicate sensitive hair-like structures filled with a conductive jelly. These organs sense the electric fields of prey when other senses fail in the fog of bloodied water, to home in on struggling or fleeing prey. These ampul­lae are an important tool on the shark’s sensory Swiss Army knife, as they do a range of other important jobs for the shark, like determining water temperature and finding magnetic fields.

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Excerpted from The Secret History of Sharks: The Rise of the Ocean’s Most Fearsome Predators by John Long. Copyright © 2024 by John Long. Available from Ballantine Books, an imprint of Random House, a division of Penguin Random House, LLC. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.