Shark attack

A smalltooth sand tiger shark can get up to thirteen feet (4.1 m) in length. NOAA.

Shark attacks—that is, attacks by people on sharks kill more than 100 million sharks a year, most of them just for their fins. More than one hundred million. Each year. That’s a lower estimate. It could be closer to three hundred million. Since 1970 overfishing has wiped out more than half of the world’s shark, ray, and chimera populations, knocking marine ecosystems off of balance worldwide.

Sharks, on the other hand, kill about five people a year worldwide. And it’s estimated they’ve killed less than five hundred people in the past five hundred years. Researchers estimate jellies kill about a hundred people a year. I don’t know of any killer jellyfish films even though they kill about twenty times more people than sharks do, but there are more than 180 killer-shark movies. Jellies just aren’t scary and they don’t have a mouth full of teeth.

A mako shark is also known as a sharp-nosed mackerel shark, and in Australia as a blue pointer. They can reach near fifteen feet (4.5 m) in length and weigh more than half a ton (half a tonne). NOAA.

There are no shark species that target people as prey. Most researchers are convinced that when a shark bites someone, it’s almost always by mistake. A starving shark might eat someone out of desperation, but apparently we don’t taste good to them since they usually spit people out and rarely try to take another bite. We don’t really have much in the way of blubber like seals do.

This prompts researchers to believe that attacks are actually cases of mistaken identity, where the shark thinks the person might be a seal, sea lion, or something else edible, especially when the suspected prey is on a surfboard, so it takes a bite to find out. From below, a surfer on a surfboard looks like a seal and a boogie boarder looks like a turtle, so a shark will investigate.

It appears that many attacks are by juvenile sharks who might still be learning what constitutes prey. In addition, many bites are on surfboards and kayaks that people just happen to be using. One of the primary preventative measures shark experts now recommend is to wear a brightly colored wetsuit—not blue or black, which makes you resemble a seal.

Sharks prefer to approach an animal from its blind side, sometimes waiting just outside the visual area until the animal turns away. They can detect which way a creature is facing without using sight, so they don’t actually see their prey until they’re sneaking up on it.

Some sharks, like the great white, prefer to come up from below. When looking up from underneath, researchers found the silhouette of a surfer on a board does resemble a fat seal or a sea lion. Even a person swimming horizontally can look like a seal. In addition, shark eyes aren’t as sharp as ours, so things look blurrier to them. They mainly rely on their other senses, and incidents often happen when there’s poor visibility. Bull sharks are good at hunting under murky conditions. People and prey also sound similar when moving in the water.

Sharks and other sea creatures that are horizontal and roughly shaped like torpedoes with faces on the front end must find us vertical creatures very odd with our long, spindly, waving arms and legs, topped by a round head with a strange-looking face on the side, instead of the end. The closest thing they’ll probably see to us is a polar bear, if they get that far north.

Swimmers and scuba divers can at least be more graceful in the water, but most of us playing in the surf or frolicking in the swells are rather awkward and clearly out of our element. To sea creatures we probably look rather like how a spider monkey trying to swim for the first time would look to us. In spite of our awkwardness, we’re clearly drawn to the water, perhaps to the puzzlement of the sharks. Still, we no doubt look more like a seal to them when we’re on a surfboard or in a kayak since our flailing appendages are less prominent. Also their vision isn’t that great.

There are no rogue sharks that are out to get people. It was an Australian surgeon named Sir Victor Coppleson who came up with this idea in his 1958 book, Shark Attack, but the idea didn’t really catch on until the 1975 movie Jaws came out.

Before Jaws, people didn’t think much about sharks. That movie created a massive panic that persists to this day and has resulted in the killing of a tremendous amount of sharks just because they’re thought to be deadly and many people falsely think the world would be better off without them. One study found that in the media, sixty percent of the time sharks are portrayed negatively, while only ten percent discuss their conservation.

Both Stephen Speilberg and Peter Benchley, the author of the book Jaws, deeply regretted the role their work played in the devastation of shark populations, and until he died, Benchley actively worked for their conservation. Benchley insisted his book was fiction, adding, “Sharks don’t target human beings, and they certainly don’t hold grudges.”

A great white shark can reach nineteen feet (5.8 m) in length and weigh more than two tons (2 tonnes). Hermanus Backpackers, CC BY 2.0 (adjusted).

He wrote that once while diving:

I raised my eyes and found myself face to face with, and not five feet away from, a great white shark.[...] I froze,[...] But the shark froze, too. And then abruptly, frantically, implausibly, the great white wheeled around, voided its bowels, and disappeared in a nasty brown cloud.[...] Could the most fearsome predator on earth, the largest carnivorous fish in the sea, have fled from a puny human, from me, like a startled rabbit?

If I have one hope, it is that we will come to appreciate and protect these wonderful animals before we manage, through ignorance, stupidity and greed, to wipe them out altogether.

Sharks have come close to extinction in the distant past, while humans have also barely made it through bottlenecks of near extinction. There’s evidence that humans nearly went extinct at least twice, maybe more times. Despite our current population, there are many ways it could happen again to both us and sharks.

Contrary to the popular false view, sharks are not cruel, single-minded predators intent on ripping people apart in furious feeding frenzies; neither are they torpedoes of death and destruction; nor are they emotion-less psychopathic killers.

Now that scientists are tagging sharks and can track them in real time, we’re learning a lot more about what they’re actually doing.

Researchers have found that great whites usually show little interest in humans. Using drones along Southern California beaches, they saw people and great white sharks in close proximity quite often, with sharks sometimes right next to or below the people. The people appeared to be unaware and the sharks only seemed curious. These were juvenile sharks, which can be up to nine feet long (2.7 m). The adults grow to twenty feet (6 m), or about the length of a full-sized school bus.

On one holiday in Australia there were thousands of people in the water of Sydney Harbor, along with a major swim event. No sharks were spotted that day, but seven adult bull sharks were there and didn’t bother anyone. Without tracking, no one would have known they were in the harbor that day.

This happens often. Researchers regularly discover sharks cruising among swimmers without the swimmers or those on shore ever being aware of their presence, since they keep a low profile. Many sharks don’t like being around people and will flee the area, perhaps because by far we’re their number one predator.

Still, that doesn’t mean it’s safe. Military diver Paul de Gelder survived being bitten by a bull shark in Sydney Harbor, losing his right hand and part of his leg. A few years later, a documentary crew took him to Fiji so they could film him hand-feeding bull sharks without a cage, giving him a chance to confront his fear. He was quickly surrounded by 150 of them. He also swam with great whites without a cage. He later told The Guardian, “Seeing them in their natural environment, changed everything for me.[...] My preconceptions vanished.” He’s now a shark expert, conservationist, and is working hard to protect sharks, explaining, “They’re not vicious, man-eating monsters.”

He has since taken a number of celebrities down to feed the sharks. They can probably get away with it since in those situations the shark would have no doubt that it’s dealing with a human. They approach out of curiosity and to get handouts, but don’t seem to have any interest in biting anyone. De Gelder said they had to take baby steps to get Mike Tyson down there, but once Tyson was there, he kept trying to pet all of the sharks.

People should be afraid of sharks, just as they would be of a lion or bear. They are wild animals that can be dangerous and unpredictable, especially when they feel threatened. But we have to realize that they are not actively hunting us and for the most part would rather leave us alone. But not always.

There are accounts of sharks and rays that seem to enjoy swimming with divers and especially like feeling the bubbles from the diver’s regulators rise up and tickle them from below.

Many divers develop personal relationships with sharks. They quickly learn to recognize individuals and each has its own personality. The sharks have sensitive skin and seem to enjoy being petted. They even seek it out from the divers they know.

A couple of fish keep an eye on a blacktip reef shark. They usually hunt in packs and generally eat small fish, crustaceans, and mollusks. © Elaine Molina Stephens, 2017.

Marine biologist Frauke Bagusche, on her dives in the Maldives, off the southern tip of India, would find herself surrounded by as many as fifteen blacktip reef sharks. Even though they seemed curious and showed no signs of aggression, they could still be startling. In her book The Blue Wonder she wrote, “On a number of occasions their excellent camouflage has given me near heart attacks when I would suddenly discover a shark swimming beside me. It is very difficult to describe the feeling of a shark, with its intelligent eyes, sizing you up.”

In Jonathan Balcombe’s What a Fish Knows, professional diver Cristina Zenato, who has been diving with sharks for twenty years, tells of how she’s often greeted by her favorite shark, Grandma, an eight-foot reef shark, saying, “She has a soft nature, and a way of approaching me with the desire to be petted and touched. She is usually very keen to come to me. Even when somebody else is down there with food and I am some distance away she will approach me before anybody else. Sometimes when I let her go she quickly turns and comes back into my lap.”

Fish—and sharks are fish—are also very sensitive to touch and some enjoy being touched. They can also recognize human faces. Balcombe and others cite anecdotes of numerous fish that rush over to their caretakers or divers to be touched, held, or gently stroked. Some large groupers squirt water at people they don’t like and one does this to anyone who doesn’t rub its head.

Most experts even dislike the term “shark attack”, since in many cases the shark is defending itself, such as when a shark is dragged aboard a boat, or the bites are made out of curiosity. These are not attacks. Calling them attacks implies an intention on the shark’s part, which may not be there.

Some sharks are territorial and when protecting their territory, they’re reluctant to back down. They will give warning signals and displays, which make other creatures retreat, but inexperienced people probably won’t understand these, and that can lead to a dangerous situation.

If you take the number of people in the world and the number of deaths by sharks, you can easily calculate the odds of a person dying from a shark, and these odds are very small. You’re more likely to be killed by a cow than a shark. You’re more likely to be killed by most everything—including vending machines—than a shark. On the other hand, if you’re a surfer, your odds go up quite a bit, since it’s mostly surfers who get bitten or die from sharks.

If you trace your ancestors back 440 million years, you’d find they looked a lot like sharks, because they were the last common ancestor of all jawed vertebrates. In other words, every vertebrate with a jaw, including you, chickens, and Tyrannosaurus rexes, descended from these shark-like fish. These are the most recent ancestors that we also share with sharks and which make sharks our distant cousins. They were called acanthodians, in case you want to add them to your family tree.

 

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