A shark,say our white Shark 26,sees in blurry low resolution,like someone who has forgotten their glasses,but his eyes are good for a fish,and even better at night. “It’s a bit insulting to the shark to say they’re bumbling along making mistakes,” Papastamatiou says. “Every now and then,probably,but not all the time.”
Guida agrees. Scientists (including Hart) have shown that sharks are colourblind,putting an end to old fears about “yum-yum yellow” attracting them to surfboards,but they can still make out contrast and contours. “Even something as small as a cigarette packet floating on the water,sharks will check out,” Guida says.
And sharks are notoriously curious – investigation or taste testing is considered a likely motivation behind many attacks. “They don't have hands,so how do you investigate something if you're a shark? You bite it,” Papastamatiou says. “Of course,it can still be devastating.”
This might also explain why human encounters with the predators typically look very different to a shark truly in hunting mode. When a white such as Shark 26 has spotted a target,he will barrel to the surface in a burst of speed so powerful he’ll often breach out of the water himself. His eyes will roll back in his head to protect against an errant flipper or tooth.
“If sharks went after surfers the same way they went after seals we’d be seeing a lot more fatalities,” Papastamatiou says. “Some attacks may just come down to how hungry a shark is,but very rarely do we see actual consumption.”
Many sharks will leave after biting a human rather than charging a second time or waiting for the victim to bleed out,as they often do with their regular prey.
Still,there are aberrations that haunt the public memory. The shark that mauled Ken Crew in the shallows of a Perth beach in 2000 then turned on his rescuer. Pearson says some Bite Club survivors have been bitten more than once or chased back to shore. “We’ve had a shark bump someone else out of the way to go for one of our guys,” he says. “And I’ve spoken to about 10 people thrown metres into the air in a stealth breach attack – thankfully,the surfboards took the brunt of it.”
In Tasmania in 2020,a boy was dragged from a fishing boat by a breaching white shark but rescued with only minimal injuries by his father as the shark let go. Papastamatiou says the boat itself,rather than the boy,was probably the target. “But it’s really guesswork,why it attacked.”
Hart notes many victims are surfers,who tend to be further out in the deeper water where bigger sharks dwell. But he thinks the mistaken identity theory shouldn’t be discounted too quickly – his own experiments carting foam seal “decoys” behind boats for white sharks in South Africa found that when the foam seal was outfitted with a flashy strip of lights,disguising its familiar silhouette,the sharks stayed away.
“And someone on the surface can look pretty similar to our foam seal.”
It’s also unclear if sharks are territorial,Papastamatiou says. “Some do have home ranges and … hierarchies. You’ll see injuries from other sharks,a white might charge another one to let it know to back off,though I’ve never heard of[these clashes] being fatal.”
But,while some of the smaller sharks may perceive us as a threat,he says the bigger species involved in most incidents (bulls,whites and tigers) are unlikely to feel threatened by an ungainly human in their ocean.
“We need to look,too,at all the times a shark was there and nothing happened. If people knew how often there was one in the water with them,they’d be shocked.”
What have we learnt from close encounters?
Australian champion surfer Mick Fanning famously fended off a white shark live on television during a competition in South Africa,and recalled later how he felt the predator move behind him as he tried to swim for shore. Some instinct told him to whip back around,to fight with his fists,rather than turn his back.
Papastamatiou,himself trained in martial arts as well as diving,admits the old punch in the nose advice likely won’t do a whole lot of good. “Obviously,you should fight back,but if I had a choice I’d be going for the eyes or the gills;they’re more sensitive to damage. My Brazilian jiu-jitsu probably won’t do much at all unless I wanted to put the shark in a headlock – definitely not advisable.”
Instead,he says,think like Mick:“Never turn your back on a shark.” If a shark thinks it can catch you unawares,you’re a much more interesting prospect than someone vigilant who might give it a fight. Papastamatiou has seen sharks bail out of charges just because a turtle glanced up and spotted them.
Can sharks really smell a drop of blood miles away?
Not exactly. It would have to be a lot of blood pooling in one spot for a decent period,and so easy to track. Shark senses are very good,particularly their hearing,thanks to jelly-like pores along their sides that detect vibrations in the water. “But that’s still not going to bring them in[from] more than a kilometre away,” Papastamatiou says. A shark might be drawn to a floating whale carcass or river mouths. An activity such as spearfishing,full of soundwaves and fish blood,is more likely to attract a nearby shark than a small cut on a hand. One impressive,though even more short-range,sharky sense is their ability to detect electrical fields produced by prey,say,from hearts beating,allowing sharks to zero in on fish,even those hiding beneath sand on the seafloor. Strong electric fields can also overwhelm this sense and so repel sharks,inspiring a range of personal deterrent devices. Many products have not been properly tested but some have shown promise,including certain electric field models and even bite-resistant wetsuits. Still,there’s no silver bullet.
Pearson shudders to imagine how he would have reacted if his own encounter with a bull shark hadn’t happened so fast,if he’d looked it in the eyes as it broke out of the water in front of his surfboard. What he remembers instead was the gaping teeth and,later,a grey shape in the roiling surf. The shark’s nose clocked Pearson in the head and his left arm became stuck between its jaws and his board as they were dragged underwater together,man and shark. “I wouldn’t say we were wrestling exactly,” Pearson recalls. “We were both stunned from the[collision so] it did the hard work for me.”
In the years since that day,Pearson has come hair-raisingly close again and again to large sharks in the waters of NSW – 12 encounters within his first 12 months back in the water. A white “sniffed[his] feet” all the way in on a wave. A bull rubbed its back against him.
Some close calls were easy to shake off. Some weren’t. “I’d tell[my mates]:‘Don’t leave me alone.’ Sometimes I just sat back on the beach and cried,thinking,can I keep doing this? Now I’m more settled,my love of the ocean is still stronger than my fear of sharks. But they don’t call me shark bait for nothing;I seem to have a radar these days. I know when to get out ... People need to listen to sightings.”
In the documentarySave This Shark, Fanning himself gets close to some of the world’s biggest sharks in an effort to understand what happened that day in South Africa and how the predators,which he now calls “the janitors of the ocean”,are faring against overfishing. “I think people expected that I’d be calling for a cull on sharks,but it’s the opposite,” Fanning says. “I learnt to dive so I could get closer to the sharks and resolve the feelings I had … Hopefully,[now] I’ll be known less as ‘the guy who punched a shark’ and more as an ocean activist.”
Shark biologist Charlie Huveneers took Fanning cage-diving with whites in the Neptune Islands,a known hotspot for the species in South Australia. It was in these waters that Huveneers and his team first noticed whites seemed to be using an interesting tactic to hunt – coming at prey from the same direction as the sun to seemingly improve their vision (and dazzle their target). They even changed direction as the sun shifted throughout the day.
“World War II jet fighter pilots did it too,” Huveneers says. “But we hadn’t seen it with a marine animal before.”
What do we know about how sharks think?
When Zenato takes tourists on reef dives in the Bahamas,she is also followed by a group of loyal “regulars”;sharks she gives names such as Grandma,Stumpy and Shredder. Some are more “popular”,others must be coaxed in for a feed,cheekier animals might be scolded for stealing bait. It’s like the whites Papastamatiou works with in Mexico;certain animals will swim calmly to the boat,he says,“and others are just – there’s no other word for it – bad-tempered”.
Researcher Catarina Vila Pouca has seen the same surprising personalities surface in (smaller) sharks she’s trained back at Macquarie University’s Fish Lab. Some of the Port Jacksons on which her team ran cognition experiments were bolder than others. The sharks could also learn from one another,recognise patterns and even count (in a sense),identifying specific quantities of dots on cards.
It’s likely such skills translate to bigger species too,Vila Pouca says,as they seem key to survival. “There’s a whole range of abilities science has assumed only happened in mammals we're now testing in fish. People think fish have terrible memories,but sharks can learn things and remember them for more than a year.”
There are also signs of learning in the wild,she says. It’s why fishermen will often complain of sharks stealing fish straight off their hooks or following their boats,and why tagged sharks released by scientists will often shoot off into the open ocean and not return to shore for months.
Huveneers says that personality and unpredictability can even show up in migration patterns. Sharks are constantly moving,not just to hunt but to return to preferred breeding grounds – usually in more sheltered reefs and mangroves where baby sharks born tough but small can be safe to fend for themselves. They don’t travel in packs but many species have been known to come together in small “clans” year after year.
“There’s even this mysterious bit of ocean off Hawaii,in the middle of nowhere,that white sharks near the US gather at the exact same time,” says marine biologist Olaf Meynecke. “We call it the White Shark Cafe. In the shark world,usually the bigger sharks move around more,but we still don’t quite know how they find each other again in all that vast ocean. It’s like a desert.”
Whites are found in every ocean on Earth. Those in Australian waters will often swim across to New Zealand,New Caledonia and the Pacific Islands. One now-famous white named Nicole (after the actress and shark enthusiast Nicole Kidman) was tracked from South Africa to south-west Australia and back again in nine months. In recent years,the CSIRO has started building a white shark family tree of Australasia using DNA samples from tagged animals. “It’s like ancestry.com,but for sharks,” a spokesman says. Analysing that data,they could estimate the true size of Australia’s white population for the first time,he says,and found it has stabilised over the past decade since protections were introduced but remains in trouble – short on breeding partners.
Why are sharks in trouble – and how do we live with them?
Sharks have swum in our oceans for the past 450 million years – their ancestors fought the dinosaurs. They are finely evolved to hunt at the top of the food chain. Zenato calls them the wolves of the sea,stopping any one species from getting out of hand and throwing off the ecosystem below.
The problem for sharks is that they also mature and reproduce very slowly. So if their populations start to decline rapidly,as they are today under unprecedented overfishing pressure,they cannot make up for the losses fast enough.
Naylor muses that,while sharks have already survived four of the five big extinction events on Earth,and will likely survive climate change too,“the one thing they won't survive is being fished out of the water by a bunch of monkeys,[without] end”.
“And there will be consequences if we remove sharks;we don’t know exactly what yet. It could be algae all over our beaches,blanketing the Gold Coast. It could be much worse.”
In the Bahamas,shark numbers are stable thanks to new protections,but they still regularly find themselves snared by hooks after being drawn to fish thrashing on lines.
“It’s the job of the shark to clean up what is hurting,what is bleeding,” Zenato says. And she now considers it her job to help them where she can.
Removing hooks from the mouth of a shark is not easy. “People say,‘Use pliers’,I need to use my hands.”
Sharks outside her regular group will turn up on dives with hooks too. “And I’ll take them out and never see those sharks again. But they know to come.”
Guida has studied the impact of shark mitigation and fishing methods on animals,measuring the build-up of chemicals in their bodies during capture. “A shark jerks just like a human when I draw blood,” he says. “Their brains,their physiological responses to pain and stress are not that dissimilar to ours.”
Even in the Great Barrier Reef World Heritage area,Guida says fishing nets can stretch for more than a kilometre. “Once something’s in a net,on a hook,flopped up on a boat or trawler,it becomes a race against time. Some species that need to swim to breathe,like the[endangered] hammerhead sharks,start choking fast.”
Marine biologist Lawrence Chlebeck at the Humane Society International says living with sharks safely is not about shark-proofing the ocean. “That’s a very Australian idea,” he says. “[Bites] are horrific,and they make us think authorities should do something,but the way to stay safe isn’t what might feel right;it’s not[vengeance].”
Research consistently shows that killing sharks – through netted beaches,baited drum lines or bullets – doesn’t stop attacks. In some cases,sharks and other marine life caught,such as turtles and dolphins,might even attract more predators to the area. In others,Guida says the measures can create a false sense of security for beachgoers. (“The nets,for example,only go up four metres.“) The death of a surfer on the Gold Coast in September was at a beach with both nets and drumlines,although proponents insist overall deaths remain low at netted beaches,even if attacks have not slowed.
Scientists now see real promise in shark surveillance programs being rolled out from South Africa to WA and NSW. In October,a loud warning from an overhead drone may have saved professional surfer Matt Wilkinson from a shark that had swum close without him noticing.
“I’m saving up my pennies for my own drone,”Pearson says. “And there’s nothing like surfing with five or six survivors – one splash and every head snaps around.
“The big question we all wonder – why did it happen? – we never really get an answer to,so[as a group] we’ve become each other’s answer.”
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As Zenato describes the swollen jaws of the sharks she helps by hand,she stresses that she understands the risks (“I would never try to remove a hook from a great white”). But still she wonders,when the animals sink down into her lap,do they enjoy her touch? The protective chainmail she wears over her wetsuit is soft against the skin.
It’s the same way we might wonder if a 500-year-old Greenland shark,born before the Industrial Revolution,has felt the ocean warming in the centuries since,as pollution spilled black and sticky into the seas.
“At the end of the day,it’s a wild animal,who knows?” Guida says. “But I remember now cage-diving with a white and in the whole 45 minutes she was close,she only bared her teeth once. It just struck me how gentle they can be,how shy they can seem.”
Zenato thinks the reef sharks come to her because they feel no threat. “Some stay for a very long time,some just a few minutes. But in that moment,they trust me.”
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