On this page:

• Acoustic shark repellents

So it’s not surprising to see sales of personal shark deterrents or repellents starting to gain some traction. But just how effective are they in preventing a shark from attacking?

Shark-repellent devices claim to reduce the risk of a shark attack by interfering with one of the many senses sharks use to detect their prey – either sight, smell, hearing, or a special sense that sharks have to detect electromagnetic fields.

Electrical shark repellents

Electrical shark deterrents claim to work by emitting a small electrical current into the water, which interferes with special sensing organs sharks have in their snout called ampullae of Lorenzini. These organs detect small electrical currents given off by their prey, such as from the heartbeat of a nearby fish. When overstimulated, the sensory organs spasm, forcing the shark to turn away.

So how effective are electrical shark deterrents at preventing an attack?

Shark Shield is the only electrical repellent on the market that’s been independently shown to be effective at deterring sharks from biting. The electrical field is created by a two-metre cord that trails behind the user. For divers and swimmers, the device is wrapped around the ankle (Freedom 7, $749), while for surfers and kayaks there’s a different model (Surf 7, $749) that requires installation directly onto a board.

While Shark Shield can deter a shark from attacking, it won’t do so every time. The most recent study of the device by scientists at the University of Western Australia (UWA) found it prevented great whites and tiger sharks from attacking most of the time, but it wasn’t always effective. An earlier study by the South Australian Research and Development Institute also found the device was effective in deterring great whites, but noted it didn’t “deter or repel this species in all situations, nor did it repel all individuals”.

And user reports back this up. A South Australian abalone diver told ÌÇÐÄVlog he knew of two people who had been attacked while wearing a Shark Shield.

But while Shark Shield has been shown to be effective at least some of the time, it turns out not all electrical repellents are created equally. UWA researchers found that electrical repellents compacted into an anklet were ineffective at repelling sharks.

As Dr Charlie Huveneers, a shark expert at Flinders University explains, “the effectiveness of an electrical deterrent partly depends on the strength and frequency of the electrical pulse they emit and configuration of the electrodes”.

The trailing cord of the Shark Shield means the electrodes are spread far apart, but the electrodes are much closer together on anklet devices, offering less protection.

NoShark ($US399) is one such anklet device that’s currently on the market, and while its manufacturer says it has “encouraging video results” of the device in action, they didn’t respond to our requests for information on their testing.

Surf Safe ($389) is another electrical device that works somewhat differently to the Shark Shield and NoShark, with the electrodes needing to be installed onto a surfboard. While Surf Safe told us it has over 1000 users worldwide and claims to have done “extensive” in-house testing, the company is still waiting on the results of independent testing.

Can electrical devices attract sharks?

If sharks use electrical currents to find their food, wouldn’t strapping an electrical device to your leg actually attract a shark to come in for a closer look?

That’s a genuine concern for some people, and we’ve been told of surfers using these devices being asked to get out of the water by others nearby.

But Huveneers told us it’s unlikely sharks would be attracted by an electrical shark deterrent.

“Even though sharks are capable of detecting minute electric fields, they mostly use this sense at close range. It’s unlikely a shark would be attracted to a personal electrical deterrent from a long distance,” he says.

Magnetic shark repellents

The power of magnetic shark deterrence was reportedly discovered by accident, when a scientist inadvertently dropped one into a tank of small nurse sharks and noticed they quickly darted away. It turns out magnets may have a similar effect on sharks as electrical fields, also overstimulating the ampullae of Lorenzini and causing an unpleasant sensation in the snout.

Both Sharkbanz ($149) and Shark Shocker ($US35) claim to work using this principle, incorporating magnets into a small band that’s worn on the wrist or ankle. These devices are considerably cheaper than electrical deterrents, but do they actually work?

Sharkbanz told us its device has been shown to repel a range of sharks, including bull sharks and small tiger sharks, but they don’t recommend it for deterring great whites. Shark Shocker didn’t respond to our requests for information on its testing.

While there have been no independent studies on the Sharkbanz or Shark Shocker devices, research into using magnets to repel sharks from commercial fishing lines has generally been inconclusive as to their effectiveness.

Dr Carl Meyer, a shark expert at the Hawaii Institute of Marine Biology, told us that while magnets could work in theory, he isn’t convinced a small magnetic band strapped to a leg would be effective enough.

“I would need to see some independent, rigorous and peer-reviewed results before buying into their efficacy as a shark repellent,” he says.

Acoustic shark repellents

Killer whales like to eat sharks, so does pretending you’re an orca stop a shark from biting you?

That’s the idea behind the SharkStopper personal shark repellent, the “world’s first and only acoustic shark repellent”, due for release early this year. The device is a small plastic band that’s worn on the leg and emits a “multi-patented acoustic sound” – a blend of orca calls and a special frequency its maker says will repel sharks.

But UWA scientists recently found orca calls had limited ability at deterring sharks in the wild. And Dr Christine Erbe, a whale vocalisation expert at Curtin University, told us that orcas live in social groups – meaning a killer whale vocalisation that works in one place, may not necessarily work elsewhere.

Erbe points out there’s also the problem of a shark figuring out you’re not actually an orca at all.

“There have been experiments playing orca calls to deter seals from fish farms, but the seals quickly figured out it’s not a real predator and started to ignore the playback,” Erbe says.

“This might happen with sharks too – we don’t know.”

Spray shark repellents

There’s evidence sharks don’t like being around their dead brethren, so SharkTec has devised a shark repellent spray (Anti-Shark 100, $US25) that contains an extract of dead shark tissue packaged into an aerosol can. The can is small enough to be carried in a pocket, dive bag or in your hand and releases a cloud of repellent into the water that SharkTec says creates a “temporary safety zone”. It’s “temporary” because the plume created by the spray eventually disperses, meaning the sharks may well come back.

SharkTec says its repellent is suitable for a wide range of users, including swimmers, snorkelers and scuba divers. The reality is a spray is only an option if there is actually time to activate it, a luxury that may not be available in a real-life shark attack.

Changing surfboard colour to repel sharks

In the wake of his great white encounter in South Africa, Mick Fanning decided to change his preferred colour of surfboard from what he called “yum yum yellow” to blue and black varieties.

The change was inspired by evidence that most, if not all, sharks only see the world in shades of grey, meaning the brightness of an object plays an important role in whether a shark sees it or not. So can a simple change of board colour really prevent a shark attack? Possibly.

“White, yellow and silvery things are more likely to be approached and bitten by some shark species than blue and green things,” says Dr Nathan Hart, a neurobiologist from Macquarie University who has studied the visual systems of sharks.

Hart says there’s one downfall though. When viewed from directly below, a surfboard will be seen as a dark silhouette, regardless of its colour. Still, he says a darker board might reduce the risk of a shark attack from the side, and could be worth a try.

Shark-deterring wetsuits

Black wetsuits have long been scorned for unintentionally making wearers look like seals. But Australian company Shark Attack Mitigation Systems (Sams) has changed this by designing a range of wetsuits that buck the all-black trend.

The design for divers features a camouflage pattern ($495) in various shades of blue, which Sams says makes the wearer blend into the surrounding water. There’s also a special wetsuit specifically for surfers ($495), which features black and white banding along the limbs. While it might make you look like a pedestrian crossing, Sams says the wetsuit is designed to send a warning to sharks that you’re not a yummy treat. 

The design resembles the markings of a banded sea snake, which may be a dangerous food option for sharks. It’s also reminiscent of a pilot fish, which live in close proximity to sharks without getting eaten.

Sams says its wetsuits are currently undergoing independent testing.

What’s the risk of a shark attack?

Spark up a conversation about sharks and it’s likely someone will throw in a stat or two about you being more likely to die from a cow kick than from a shark attack. As comforting as that may be, when you’re 20 metres from shore with a plank of fiberglass between your legs or stretching out as part of your morning swim, the likelihood of a cow kicking you becomes extremely slim, while the chance of being eaten by a shark increases. But only ever so slightly.

“Cases of sharks devouring humans are a very rare event,” says Dr John West, curator of Australia’s shark attack files at Taronga Zoo. “98% of shark attacks involve a bump or a single bite, and then the shark swims away.”

That said, a single bite can potentially be enough to cause death or permanent injury – not to mention the emotional trauma. And it does appear that reports of shark attacks are on the rise.

In the 1990s, the average number of unprovoked attacks in Australia was 6.5 per year. That figure jumped to 13 per year over the last decade. In 2015 alone there were 22 unprovoked attacks, including one fatality and 13 injuries.

To put those figures into perspective, more than 1000 people are killed on Australian roads every year. Globally more people died last year taking selfies than those who’ve been killed by a shark.

And if you’re fearful there are more sharks about, West says it’s a rise in people, not more sharks, that’s driving the rise in attacks.

“More people are going into the water and they’re going into the water more often. This increases the risk of encountering a shark,” he says.

Are shark repellents guaranteed?

The websites of personal shark deterrent manufacturers feature videos of the devices in action and testimonials from happy customers who feel safer using them. But if you’re looking for a shark deterrent that’s 100% effective, you’re going to be looking for a long time.

All the products we came across clearly state there’s no guarantee they’ll prevent a shark attack. One manufacturer even likened their product to a seat belt, saying that while seat belts reduce the risk of a fatality in an accident, they don’t completely eliminate it.

This may be true, but seat belts have to comply with a standard to ensure they work as intended, giving the user confidence in the protection they afford. With personal shark deterrents, very little independent testing has been done, making it hard for consumers to judge if they truly work or not.

“The ability to advertise a device as repelling sharks without having performed adequate testing can be misleading,” says Dr Huveneers.

“It’s important the general public is properly informed about the devices they are purchasing to ensure they make informed decisions about the potential risks.”

Huveneers also warns that people using these devices should know their limitations, even if they’ve been shown to work at least some of the time.

“There’s a danger with personal deterrents that increased perception of safety may lead to the users taking more risk than they normally would.”

Are shark repellents worth the cost and effort?

If fear of a shark attack is stopping you from entering the water, then forking out for a personal shark deterrent may provide some peace of mind. But be aware of their limitations – many devices haven’t undergone independent testing, and no device will protect you in all circumstances. And remember, there are ways of reducing the risk of a shark attack that don’t cost you money or make you dress like a sea snake. It’s a good idea to follow these tips – irrespective of whether you’re using a deterrent or not.

Reduce your risk of a shark attack

The following tips are provided on the  website as ways of minimising your risk of a shark attack:

• Always swim, dive or surf with other people.
• Avoid dirty or turbid water, which make it hard to see a shark approaching.
• Avoid going into the water at dusk, dawn or at night, as many sharks are more active during these times of the day.
• Avoid swimming or surfing around river mouths, especially after rain.
• Don’t swim with pets.
• Be careful wading through shallow water, particularly where kelp is about, as you may accidentally step on a wobbegong shark.
• Take off jewellery before entering the water. Jewellery reflects light in the same way fish scales do, and sharks can be attracted to the reflected light.

Shark-reporting app Dorsal

Wouldn’t it be good to know if a shark has been seen in an area before you enter the water? That’s where  can come in handy. Dorsal is an app that provides real-time information on shark sightings, crowd-sourced from beachgoers around the country. 

The app is free on iPhone and Android, and allows users to enter details about shark sightings, including information such as time of sighting, the size of the shark, and what type of shark it was (if known). 

Dorsal also features the latest sightings and alerts from authorities, including helicopter surveillance and lifeguard patrols. Once submitted, the information is immediately relayed to all users via the app and the .

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On this page:

• Why epoxy?
• What's the difference?
• How is an epoxy board made?
• How is a traditional fibreglass board made?
• Surfer trial: epoxy vs fibreglass
• Results
• Taking your first surfing steps
• Unwritten laws

Why epoxy?

Makers of epoxy surfboards claim they’re more suitable for novice surfers compared to traditional fibreglass surfboards, thanks to their lightweight construction and ability to take more punishment than fibreglass boards – both important considerations for those just getting started.

Epoxy boards grew in popularity from 2006 due to necessity more than anything else, following the closure of the Clark Foam factory in December 2005 – which led to a major worldwide shortage of the polyurethane foam used in the production of traditional fibreglass boards.

What’s the difference?

Surftech, Firewire and Resin8 are examples of companies producing epoxy surfboards. They advertise these boards as being more durable and more buoyant than a traditional fibreglass board, ideal characteristics for people wanting to get back into surfing after a long layoff period or beginners who may require a bit of help when paddling for a wave.

Epoxy boards have a more plastic-looking finish compared to traditional polyester (fibreglass) boards. Epoxy construction has been used in the windsurfer industry for several years and looks set to remain a popular option in the surfing industry too.

Although professional surfers have ridden epoxy boards in competition, Taj Burrow being the main example, they are still primarily aimed at the beginner or recreational surfer, as well as older people wanting some help to get onto the wave.

The most significant difference between the moulded epoxy boards that we tested and fibreglass boards is that you know that an epoxy board from a particular mould is exactly the same size, shape and weight as the next one.

How is an epoxy board made?

An epoxy board starts with a light polystyrene foam core, which is sandwiched between high-density foam sheets and reinforced with glass and epoxy resin. The board is then compression-moulded, creating a lightweight board with a hard outer shell. 

There are two types of polystyrene used:

• Open-celled polystyrene is a beaded foam similar to an old-style esky, but the open cells suck up water if dinged.
• Extruded polystyrene foam, which absorbs less water but is more expensive.

None of the mass-produced epoxy surfboards are made in Australia. They’re produced in countries such as Thailand, using designs created and by a master shaper.

While it’s possible to get custom-made epoxy boards, the labour involved makes them a lot more expensive. Many professional surfers argue that the inability to have an epoxy board hand-tuned by an experienced shaper or sander is a disadvantage, but unless you’re getting ready to head out onto the world circuit this probably won’t be a major issue for you.

How is a traditional fibreglass board made?

A polyurethane/polyester board or ‘fibreglass’ surfboard involves a significant amount of hand shaping in both the preparation of the core or polyurethane foam blank, and the final sanding to get the finished product just right.

The blank is shaped as far as possible to the board’s specifications and a piece of wood or ‘stringer’ is incorporated into the middle of the blank for added stiffness and durability. The blank is then covered with a fibreglass cloth and laminated with polyester resin. The board is left for a period of time to allow the resin to set, and then the board is sanded to the final specification.

Surfer trial: epoxy vs fibreglass

So, while epoxy boards sound like the perfect solution for beginners or surfers getting back into the sport, we decided to look at the two major surfboard options to see how well the claims pan out.

How we tested

We bought a series of surfboards at the popular sizes of 6’1″, 7’0″, 7’11” (mini Mal) and 9’6″ (longboard) in both the epoxy and traditional fibreglass versions, and gave them to five surfers of varying skill levels to get their feedback.

All the boards in the test were weighed and measured for length, width and depth. Ease of use was assessed via a field trial at a well-known surf spot called ‘The Farm’ just south of Wollongong. Each board was trialled by the five surfers, who then answered a questionnaire about them.

Following ease of use testing, one polyester/fibreglass board and one epoxy resin board were subjected to a series of durability tests, including impact resistance – dropping weighted wooden blocks from various heights onto the rail (the side) and the top of the surfboard. Imprint resistance was also assessed to replicate general use out in the water.

At the end of testing, the depth at each pressure point was compared with the pre-test depth.

Results

Overall, the epoxy board seems to be able to handle the general day-to-day bumps, dings and impacts better than the fibreglass board, though there was no major advantage with either when it came to a more forceful impact out in the surf.

There’s no doubt that our panel found the epoxy boards easier – to paddle, catch a wave and turn. But the more proficient surfers found a slight loss of control when carrying out more radical moves. Duck diving, where a board is pushed under an oncoming wave, was found to be a bit more difficult when using an epoxy board because of the increased buoyancy.

When it came to picking a favourite, there wasn’t a strong preference for one material over another from our triallists; some even liked a mix of epoxy and fibreglass boards depending on the size.

Although there were clear differences between the epoxy boards and the fibreglass boards according to our triallists, the differences were harder to quantify in our test labs. Regardless, there is no doubt that epoxy boards provide another option for surfers of varying experience and fitness levels, and that can only be a good thing.

Triallists’ feedback

Except for duck diving, the epoxy boards scored the same as, or better than, the older fibreglass boards, although in most cases the difference was only slight. While all of our triallists noticed the added buoyancy of the epoxy boards, there was no overriding preference for one particular size or material across all five of the testers.

Jye – Ex-World Title competitor 

• Favourite boards: 6’1″ epoxy, 7′ and 8′ boards in fiberglass, and 9’6″ epoxy.
• 6’1″ boards: “Fast reactions and easy to paddle.”
• 7′ boards: “The epoxy was harder to duck dive, although I got used to it and was working well through the flat sections. But I’d probably lean more towards the polyester board.”
• 8′ boards: “The epoxy floated and paddled really easily, but was harder to duck dive. I’d go with the fibreglass board as the epoxy was just a little too thick around the rails.”
• 9’6″ boards: “Nose ride on the epoxy was very good, bit more responsive and a lot easier to get used to.”

Dan – Australasia Pro Junior Series competitor

• Favourite boards: Best performance – 6’1″ epoxy. Easiest to paddle – 7′ epoxy. Most fun – 8′ fiberglass.
• 6’1″ boards: “The epoxy was easier to paddle and better getting through the back sections of the wave.”
• 7′ boards: “The epoxy was easy to paddle.”
• 8′ boards: “Great fun on points with the fibreglass.
• 9’6″ boards: “The fibreglass was a lot more tanky (heavier) than the epoxy.”

Tony – Surf school teacher

• Favourite board: 9’6″ epoxy.
• 6’1″ boards: “A little faster (epoxy), maybe too much buoyancy for my weight but it was very fast.”
• 8′ boards: “The epoxy was lots of fun, paddles very well and manoeuvers very well, but in the fat sections can get bogged down.”
• 9’6″ boards: “Definitely go with the epoxy board as it keeps the speed up no matter where you are on the board.”

Tess – Seven years’ surfing experience

• Favourite board: 6’1″ fibreglass and 9’6″ epoxy.
• 6’1″ boards: “More slippery on the wave as the epoxy is more buoyant and sits up a bit higher. I’d probably stick with the fibreglass.”
• 8′ boards: “I’d stick with the epoxy although it’s not very fast, overall there didn’t seem to be a big difference on the wave but the epoxy felt lighter and easier to use.”
• 9’6″ boards: “I’m into the extremes and loved the epoxy big mal.”

Rhys – Recreational surfer

• Favourite board: 8′ fiberglass.
• 8′ boards: “Of the 8′ boards, I found the fibreglass board gave me more control.”
• 9’6″ boards: “I really enjoyed the epoxy 9’6″ board as it felt a lot lighter than the fibreglass board not as heavy in the turns.”

Taking your first surfing steps

No matter how good your new board is, if you don’t know how to use it properly you’ll never enjoy the experience to its fullest. Also, a sound knowledge of the ocean environment and how to recognise shifts in the surrounding weather patterns is crucial to ensure that you don’t become another tragic statistic.

If you’ve ever wanted to be at one with the wave, now is a great time to learn to surf by joining one of the many surf schools available around Australia. The lessons learned will not only help you get up and away more effectively, you’ll also gain a greater appreciation of the power of the sea, and how to recognise what to do in dangerous situations. provides information on your nearest surfing school in each state, or you can visit your local surf lifesaving club for more information on local schools.

Although not considered on par with fibreglass boards when it comes to performance on the wave, a soft-top board can be great fun to learn on while still being able to satisfy surfers as they become more experienced. The soft-top was designed to fill the gap between sponge boards or ‘coolites’ (which offer safety but lack performance) and fibreglass boards (which offer performance with little safety and poor durability).

• Fins are an important part of the board’s performance and can be altered to suit both the surfing conditions and your experience. Generally, a larger fin area will give you more drive through the wave, while smaller fins will allow you to ‘skate’ across the wave. When fitting your fins, make sure the central fin is concave on both sides and that those on the left and right side are concave on the outside.
• A leg rope is a crucial piece of equipment, as it means you don’t have to swim back to shore every time you fall off your board. A standard length leg rope of around seven or eight feet should be fine for most situations, unless you plan on going out in very large surf, then you may want something a little longer.

Unwritten laws

(disregard at your peril)

Learning how to co-exist out in the surf can often be as important as learning to stand up on a surfboard, with several ‘codes’ to adhere to if you want to ensure a trouble-free day at the beach. 

Rules such as giving way to the person on your inside (on your left if you’re going right on a wave, and your right if you’re going left) will keep potential conflict to a minimum.

Also, if a person has ‘My Brother’s Keeper’ tattooed across their chest, let them have the wave no matter what the circumstance!

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