Tactics and Tech to Help Save You from Being Eaten by a Shark

What would you do if you came face-to-snout with a shark?
Christopher McFadden

There are two kinds of people in the world. Those who cannot even dip their toe in the sea for fear of sharks, and those who swim out with apparent reckless abandon. 

While never entering the sea will certainly prevent you from being attacked by sharks, this also comes at the cost of cutting yourself off from a world of beauty and adventure, not to mention the fun of swimming. But the alternative, while highly rewarding, does attract the admittedly vanishingly small chance of being bitten by a shark. 

For the more adventurous among us, what exactly can you do should a shark take a liking to you? 

How can you avoid being attacked by a shark?

Shark attacks are incredibly rare, but they can and do happen. In some instances, shark attacks can be so horrendous that they become indelibly marked in our cultural history. 

One of the most famous, well infamous, examples is the sinking of the USS Indianapolis. On her return journey from dropping off one of the first atomic bombs to the Pacific Theatre, the ship was targeted and sunk by a Japanese submarine. 

She sank in less than 12 minutes, and of her total complement of 1,195 hands, 300 sank with her, leaving the remaining 890 to their fate in the Pacific. Of these, only 316 were ever recovered alive. The rest died of either exposure, dehydration, saltwater poisoning, and, of course, one of the most notorious sustained shark attacks in recorded history. 

But, this was very much the exception to the rule. In the vast majority of cases, sharks very rarely attack, let alone kill and eat, human beings. According to authorities on the subject, like the Florida Museum's Shark Attack File, only 129 attacks were recorded worldwide in 2020. 

Of those, somewhere in the order of 57 were apparently unprovoked, meaning it was an incident, “where an attack on a live human occurs in the shark’s natural habitat with no human provocation of the shark.” 

Such attacks, for the most part, are from sharks taking "test bites" where the shark is taking a sample in order to explore whether something is actually edible or not. Since sharks lack appendages like hands, this is their only way to "explore" objects of interest.

And, of course, not all sharks are potentially dangerous. The most threatening species is the great white shark. Bull sharks, hammerheads, bronze whalers, Galapagos grey reef, silvertip, tiger sharks, blacktip, and whitetips have also all been known to bite humans. But many other species, including some of the most common, are not known to attack humans.

how to survive a shark attack
Source: John Voo/Flickr

To put that figure into perspective, you are much more likely to be killed by a bee string or in a storm. Given the large amounts of people who use the sea for recreation, this figure is incredibly low. So, as it turns out, a better question might actually be "why don't more sharks attack people?" 

But is there anything you can do if you come face-to-face with one of the world's most ancient and efficient predators? You'll be glad to find out there is. 

The very first thing to do is reduce your chances of being around sharks in the first place. When you enter the water, you are entering their domain, not yours.

It is their home, their world, so try to take responsibility for your actions. Treat the threat of sharks seriously and you will be more likely to survive your little adventure into the sea. 

Most sharks hunt at night, although they will feed at any time. However, most people who are attacked by sharks are swimming in the daytime. This is because daytime is when there are more people in the water. But if you are in an area where dangerous sharks have been sighted, you may want to stay out of the water at night.

During hours of low light, sharks may mistake swimmers or surfers as a seal or sea lion. For the same reason, wading or swimming near a channel where the water is murky is also not advisable, especially at dusk when some sharks, such as the bull shark, are conditioned to feed. White sharks also frequent areas with deep channels and drop offs or canyons. 

Both anecdotal and scientific studies seem to indicate that sharks are more likely to attack if they can detect the bioelectrical activity of your skin rather than it being "masked" by things like clothes or a wet suit. The sensing organ of a shark, called the ampullae of Lorenzini, can detect electric fields produced by living things.

Some scientific experiments also indicate that sharks can distinguish light colors from dark and that they may even be able to distinguish colors. There is some evidence to suggest that yellow, white, and silver colors may attract sharks. Similarly, wearing shiny jewelry or bright clothing in contrasting colors is also not advised as it can resemble fish scales when it catches the light.

Many divers think that clothing, fins, and tanks should be painted in dull colors to avoid shark attacks. However, others argue that a dark silhouette may also resemble shark prey. 

Sharks can detect blood in the water from miles away. However, contrary to popular belief, sharks are not especially attracted to human blood. A shark is more likely to be attracted to a bleeding fish or sea lion than a human being with a cut. However, sharks’ curiosity attracts them to unusual creatures or activities in their environment. So, although blood itself may not attract sharks, its presence combined with other unusual factors (such as flailing or thrashing in the water) can excite the animals and make them more prone to attack.

This is especially true for oceanic whitetip, blue, and silky sharks, which have no instinctive fear of humans and prey primarily on large, wounded, or thrashing animals in the water.

Another key tip is to avoid areas where sharks' favorite prey, like seals, are present, or where fish are regularly cleaned. 

But what can we realistically do should the freak event of coming face-to-snout with a shark occur?

How can you survive a shark attack?

Should the nightmare scenario happen, is there anything you can really do to survive an encounter with a hungry shark? 

stop a shark attack
Source: Inside the Magic/Flickr

According to various experts on the subject (some of who have actually survived just this unfortunate event), the first thing to do is not to panic. While this is easier said than done, it is incredibly important you remain calm. 

Your instinct will likely be screaming at you to get away from the shark, but thrashing and splashing in the water is exactly the kind of behavior that will trigger the shark into its "predatory mode". 

Remember, just because you happen to be in the company of a shark, doesn't necessarily mean you are on the menu. Although, if you do chance upon a starving shark, your chances of survival are, unfortunately, pretty low. 

Another key tip is to try and maintain eye contact with the shark. As with other animals, like dogs, for example, sharks are very responsive to assertiveness. Apex predators are used to their prey trying to escape, not standing their ground and fighting back.

While you are, quite literally, out of your depth in the water, you are also a predator at heart. Let the shark see that you are not afraid and keeping track of it and it will be less likely to attack. Keeping your eyes on the sharks also helps you track where it is and avoid surprise attacks like hit-and-run, and bump-and-bite attacks commonly employed by sharks. 

Swimmers and divers have reported that looking the fish straight in the eye, swimming towards it, showing extreme aggression, and fighting the shark caused sharks to break off attacks. In fact, most shark attack victims never see the shark before being bitten. So, if you are in the water and feel something brush up against you, it is well advised to get out of the water as soon as possible to see if you have been bitten. There are various reports of people not realizing they've actually been bitten in the past. 

If a shark does come too close for comfort, you can give it a gentle push away from you, enough to show the shark you are not a pushover.

Hopefully, that will be enough to save your bacon, but should the shark decide to attack you, you don't really have much choice in the matter. 

If this does occur, most advise you to fight back with all you've got. Kick, punch, and gouge its eyes, gills, and nose if you can. Playing dead will not save your life, you need to be aggressive and literally fight for your life. 

If you have a weapon, like a knife, stab at the soft parts and avoid hitting the top of the shark as its skin is too thick to have much effect. Hopefully, this will be enough to put the shark off and leave you alone. 

If you are bitten and have been lucky enough to scare the shark off, you need to get out of the water as soon as you are able. If you can, especially if you have been bitten on the arm, try to raise the wound above your heart to stem the bleeding as much as possible. 

fight a shark
Source: michael fontenot/Flickr

If you can, use something as a makeshift tourniquet, such as a surfboard leash, that would be even better. Another important piece of advice is to never look at the wound either. 

This will only raise the chances that you send your body into a state of shock. All you focus needs to be on getting yourself, and what remains of your body, to safety as soon as you are able. 

What technology exists to help prevent shark attacks?

The above strategies are all well and good, but chances are if a shark gets you in its sights, and it likes the "cut of your jib", you'll be very lucky indeed to survive a shark attack. For this reason, various companies and research groups have been working for several years on devices that will ward sharks off when you are in the water. 

Generally speaking, shark repellent options range from those that seek to confuse the shark's electroreception, drive them away with chemicals, scare them off using sound, track and monitor shark activity and inform the public, try to hide you from sight, or provide you with some way of leveling the playing field should you be attacked. 

Here we've included some of the most interesting examples from these broad categories. There are, needless to say, many other options on the market, but these are the ones that appear to have the best utility, in no particular order. 

1. A band that interferes with a shark's electro-receptors

shark repellent tech sharkbanz
Source: SharkBanz

One interesting example of a commercially available shark repellent is the SharkBanz 2. It requires no batteries or chemicals and apparently works by confusing an incoming shark so it leaves you alone. 

According to the manufacturer, this device uses "patented magnetic technology" developed by marine biologists to deter sharks from attacking you. The device is allegedly verified by independent third parties from the School of Coastal Environment Department of Marine Science at Coastal Carolina University.

The device incorporates permanent magnets, particularly Neodymium-Iron-Boride and Barium-Ferrite magnets that are said to be able to passively produce enough flux-per-unit to overstimulate the Ampullae of Lorenzini (the organ in some sharks that detects magnetic fields), enough to disorientate a would-be attacking shark. The device appears to only be effective at a few meters range, so the utility of such a device on a shark swimming at full bore is probably minimal. 

However, it would probably be pretty effective against bump-and-bite attacks. 

The device is, by all accounts, the product of over a decade's worth of peer-reviewed scientific research. It has, according to SharkBanz, been tested, and found to be effective at deterring various shark species like the Hammerhead shark, Bull shark, Great White shark, Australian blacktip, and several other species. 

Sounds promising, but the manufacturer does warn that the band has not been fully tested on all species of shark. They also note that sharks can be very unpredictable and there is no 100% foolproof way to ward off sharks other than not being in the water in the first place. 

"Any human activity in the water near sharks must always be considered as possessing a considerable degree of risk which is assumed solely by the wearer," they point out.

Sound advice. 

2. This device actually attracts government rebates for using it

shark repellent tech surf+
Source: Ocean Guardian

Another interesting shark repellent technology is the Ocean Guardian Surf+. Developed by Ocean & Earth and former professional surfer Tom Carroll, resident owners of this device can actually apply for a $200 Australian Dollar rebate from the Government of Western Australia. 

The device is designed to be fitted to surfboards and includes a streamlined electrode and black antenna and comes with a transferable power module, a charging dock, and one tail pad/antenna. Other variants also exist for mounting on boats, fishing lines, diving suits, and barriers. 

According to its manufacturers, this device is the only one of its kind on the market that has been scientifically proven to work. Similar in principle to the SharkBanz 2 above, this technology works by interfering with a shark's "Ampullae of Lorenzini”.

Using its "Shark Shield Technology", the device generates a powerful three-dimensional electrical field that, "causes spasms, turning the sharks away."

"When a shark comes within a few meters, the field [emitted by the device] causes the shark to experience muscle spasms. This does NOT harm the shark in any way, merely producing a high level of discomfort. Shark Shield Technology is the world’s only scientifically proven and independently tested electrical shark deterrent," claim the manufacturers. 

While this might sound a little fanciful, various scientific studies have actually been conducted using the device on baited canisters and sharks in the wild. One particular study showed that from 322 encounters involving 41 individual Great White sharks, only one came close enough to make contact with the canister. 

In all other cases, the sharks steered clear. However, it should be noted that the "target" in question was a bait canister and not a living target - like a human being. However, there are some convincing customer reviews, if they can be believed of course.

3. Use acoustics to scare away sharks

shark repellent tech sharkstopper
Source: SharkStopper

SharkStopper is another interesting device that claims to be pretty effective at warding of wannabe killer sharks. The device can automatically turn itself on when submerged in water (and off when not submerged) and can operate for around 4 hours on a fully-charged battery. 

The device emits an acoustic frequency that has been shown to repel more than ten of the most dangerous species of sharks around the world. SharkStopper emits a frequency that emulates the sound of hunting killer whales in the wild.

Since killer whales are one of the few ocean predators that include large sharks on their menu, most sharks are, quite wisely, not keen on hanging around if they are within range. 

According to its manufacturer, the device has consistently proven to repel sharks that come within 5 and 10 meters of an active device within a baited location. 

Various options are available including variants that can be worn on either an adult or child's leg using an adjustable strap. Other options also exist for fitting to diving equipment.

The device is fairly light and weighs approximately the same as a regular smartphone. 

4. Anti-shark repellent sprays actually contain dead-shark extract

shark repellent sprays
Source: Ed Quinn/Flickr

One of the oldest, and frankly, least-reliable shark repellent options is anti-shark repellent sprays. Older examples are based on the concept that sharks are not fond of being around the "smell" of other dead sharks.

To this end, such sprays contain extracts from dead shark tissues. Such sprays have been in development as early as World War II when armed forces hunted for ways to keep their naval personnel and aviators safe when stranded in the water. 

Modern variants on these sprays tend to incorporate copper acetate, and other ingredients which mimic the scent of a dead shark. Some include dark-colored dyes to act as a visual screen for users in the water.

One notable example was the product "Shark Chaser". Used extensively between WW2 and the early-1970s, this product has an efficacy of around 70%, give or take.   

Another interesting anti-shark spray is based on the natural excretions of fish like the finless sole. A natural form of defense for the fish, the active ingredient is a chemical called pardaxin that acts as a severe irritant to sharks' gills. 

In 2017, the U.S. Navy announced that it planned on developing an anti-shark spray based on the chemical composition of hagfish slime. This slime is able to clog up predators' gills, causing it to gag, choke, and flee. If this can be replicated, so the U.S. Navy believes, it could prove to be a very useful means of keeping naval personnel out of danger. 

These sprays are unlikely to keep you safe for long, but they should be able to buy you enough time to get to safety. 

5. Unmanned aerial drones might be the future of keeping you safe from sharks

Rather than relying on devices attached to your surfboard or person, it might be a better idea to get a real-time "heads up" that sharks are nearby, without ever getting into serious danger. This is where equipment like drones might just be the future of shark attack prevention.

The logic is simple - have unmanned drones stationed at strategic points around a public swimming or surfing spot and keep watch. When sharks are spotted, lifeguards or other officials can immediately warn swimmers and other water recreationists that sharks are nearby. 

This is exactly what the Australian Government plans on doing with around 80 drones planned to be deployed around many of their most popular public beaches. The program forms part of a larger initiative by the Australian Government to reduce to a minimum the number of shark attacks that take place each year. 

The drones, according to Australian Agriculture minister Adam Marshall, will feature special tech to help identify the size and species spotted. These specialized drones will also be used in conjunction with more traditional "eyes in the sky" solutions like spotter helicopters. 

6. "Smart" drumlines are another interesting tech keeping swimmers safe

anti-shark tech smart drumline
Source: Shark Smart

Also being developed in Australia, another approach to preventing shark attacks is to use specialist gear to trap sharks far away from a beach. Called a "SMART Drumline", these devices consist of baited canisters connected to GPS-connected control units that can notify authorities when a shark has been caught on a hook. 

SMART in this context is an acronym for Shark-Management-Alert-in-Real-Time. The setup is anchored to the seabed and consists of a set of two buoys as well as a satellite-linked GPS communication unit attached to the baited hook. 

When a shark takes the bait, literally and figuratively, a special magnet attached to the bait line is released from the main communication unit, triggering it into action. 

Specially trained crews then make their way to the drumline, capture the shark, tag it, and release it far away from its current location. 

The tags include a series of other devices designed to help track and monitor movements once the shark is released. This includes an external acoustic tag that allows a tagged shark to be detected by an array of shark monitoring stations as part of Australia's "Shark Monitoring Network". 

The tags also include pop-up archival transmitting (PAT) technology that collects data on water depth, temperatures, and broad-scale location data that is transmitted at regular intervals.

The "SMART Drumline" recently completed testing near Gracetown, Australia, and has shown that response vessels are able to reach a triggered buoy in less than 30 minutes. These drumlines are primarily being used to target Great White sharks, but most shark species could, conceivably, be controlled using the same technology. 

7. Shark attack prevention? There's an app for that too

anti-shark-tech-app
The "SmartShark" app notifies users of recent shark sightings in real-time. Source: Smart Shark

Another approach being tested by various authorities around the world to reduce the risk of shark attacks are specialized smartphone apps. Usually used in conjunction with physical monitoring and control strategies, these apps are designed to allow members of the public to report sightings of sharks and alert everyone who accesses the app. 

One example, Sea Sense, is free to download, gives users alerts on new sightings and tagged shark detections, and provides general information about different species of shark and shark behavior.

Developed by the Western Australian Government's Shark Smart department, the app is proving pretty popular for local residents and frequent beach-goers. While an app cannot physically prevent you from entering the sea, it offers users a heads-up of the likelihood that their day might be ruined.

Other similar initiatives exist in other shark-prone areas of the globe including the United States. One particular app called The Atlantic White Shark Conservancy Sharktivity App provides information on recent sightings of sharks, and also provides information on shark movements and projected future destinations. 

Like the Australian app, the basic idea behind it is to keep people safe by giving them as much information as possible to allow them to make an informed decision on whether it is actually safe to enter the water at a particular time. The apps are also designed to help build awareness among the general public of how to coexist with these ancient and magnificent animals to keep both them and human beings safe. 

8. Dress to not impress (a shark)

anti-shark tech dazzle camo
Source: The World

We've already touched on advice from shark experts not to wear jewelry or brightly colored/contrasting colored clothing when swimming above. But, there is some specialized gear on the market that are specially designed to help you NOT stand out when bobbing around in the ocean. 

Specially camouflaged surfboards and wetsuits, for example, can be used to help you blend into the background and avoid catching the attention of a passing shark. While different species of shark have varying visual acuity, most, if not all, have relatively poor eyesight when compared to humans. 

It is this physical trait that specially designed shark-repellent wetsuits and surfboards aim to exploit. Similar in principle to dazzle camouflage on WW2-era warships, this technology aims to break up the silhouette of a single body with bold stripes or patterns.

In the wetsuits, “you’re not a contiguous body, you are a few blobs", explained Shark Attack Mitigation Systems founder Craig Anderson to the National Geographic. Most importantly, according to Anderson, they prevent you from resembling something like a seal. 

Such camouflaged equipment tends to come in two main types; black-and-white or aqua-blue. 

The former is designed for use at or near the surface of the sea. Here, what you wear doesn't really stop you from being silhouetted against the sun. For this reason, the striking black and white patterns aim to make you less obvious. 

The latter is more suitable for underwater activities - especially in slightly deeper water. Each color matches a color at a particular time of day, making that part of the suit virtually invisible to the shark. Like the black-and-white suit, this breaks the swimmer’s silhouette and confuses the shark.

The efficacy of this camouflage is pretty questionable, especially if the shark is close enough to rely on its suite of other prey-searching senses, but anything is better than nothing.

9. These lights apparently scare off sharks

anti-shark tech lights
Source: Chris Hills/Flickr

Another interesting innovation comes from the University of Western Australia’s Oceans Institute. Researchers at the institute are experimenting with an innovative light system that can be fitted to the underside of a surfboard to make them look less like seals. 

In fact, some of the major research members were also responsible for the development of the dazzle-camo wetsuits we mentioned earlier. 

Like some other solutions above, the principle is to make the surfboard (and surfer) look less like a large seal. The lights basically break up the silhouette of the board - at least that's the theory. 

The team tested their proposal by attaching their light system to decoy seal targets that are commonly used to study how sharks hunt and attack their prey in the wild. If the hypothesis is correct, the decoys with lights should be less attractive to sharks. 

And the results? Quite promising, as it turns out. 

After a series of tests, the system appeared to correlate positively with reduced attacks on the decoys. So much so, in fact, that the researchers are now teaming up with Sydney's Taronga Zoo and New South Wales state authorities to design a similar lighting system for surfboards. 

10. If all else fails, prepare to fight for your life

"The best-laid schemes o' mice an' men," as the saying goes, are never foolproof. Even with all of the above tactics and tech, there is still a chance that you could become the victim of a shark.

Should this happen, there are some options on the market or in development that could give you a fighting chance of, well, fighting off a shark. 

When it comes to defense, various types of "armored" wetsuits exist that provide you with some chance of surviving a shark attack. One example, currently being developed by Flinders Unversity, consists of two types of protective fabrics that incorporate ultra-high molecular weight polyethylene fibers - often referred to as the ‘world’s strongest fiber’ - into standard neoprene.

Field tests have shown that this new material offers some protection against the powerful bites delivered by sharks, which is promising. Other examples include using a material similar to kevlar that helps prevent blood loss after an attack.

Other options include chainmail-type armored suits that have been shown to provide some significant protection against a shark bite. In all cases, however, these "armored" wetsuits cannot protect you against blunt force trauma, or other injuries associated with sharks shaking you around like a toy. 

With regards to going on the offensive, various options have existed for some time. One of the most notable is the "powerhead" or "shark stick".

A modification on the traditional spearfishing device, these sticks incorporate projectile heads that can be used to mortally wound a shark at arm's length. Other options include a kind of underwater cattleprod that can be used to deter a shark from coming close. 

Specialized blades also exist that compressed gases to freeze the internal organs of a victim animal, or alter their buoyancy, forcing them to the surface.

While these strategies and tech are all very interesting, the only truly effective way to avoid a shark attack is to never actually enter the sea. So long as humans continue to enter the domain of sharks, either accidentally or intentionally, we will simply have to put up the very rare fatal encounter until a 100% effective shark deterrent can be found. 

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