Making a charge against shark attacks
This year there's been a few new players in the shark deterrent industry. On the back of shark attack clusters in Western Australia, Northern NSW, and Reunion Island, the need for safety is getting a strong push. It's spurred the industry to create many inventions, the latest being the Freedom+ Surf from Shark Shield.
Freedom+ Surf creates an electrical field that extends down into the water below the surfer. The manufacturers claim it's the world's only scientifically proven and independently tested electrical deterrent.
With surfers' lives at stake the shark deterrent market is starting to heat up. Swellnet recently spoke to Lindsay Lyon, CEO of Shark Shield, about the upcoming release of their electrical shark deterrent made specifically for surfers.
Swellnet: How long has Shark Shield, the company, been around?
Lindsay Lyon: Shark Shield was founded in 2001 in South Australia. The company first licensed technology from Kwa Zulu Natal Shark Board in South Africa in the late 90s and then went on to develop a range of electrical shark deterrents over the past fifteen years.
There's been a few new entrants in the shark deterrent industry, how does yours - specifically the Freedom+Surf - differ from other technologies?
The Shark Shield FREEDOM+ Surf is an electrical deterrent. It's the world’s only scientifically proven and independently tested electrical deterrent. Other products on the market include sound, sprays, and magnets. Choice Magazine recently released a story [which can be found here] noting that these products have no independent research supporting their claims.
There are only really three sharks of interest with respect to serious attacks: Whites make up 51%, Tigers 18%, and Bulls 17%. The peer reviewed research about to be released from the University of Western Australia shows that Shark Shield is effective 90% of the time, the ability if you like to remove 90% of the risk, with the majority of the research on whites.
The UWA research found that even lower powered electrical deterrent anklet devices to be ineffective. Given this, it is extremely unlikely that a non-powered magnet would have any effect in deterring a shark.
How does it work?
Sharks have small short-range electrical receptors in their snouts used for finding food. Shark Shield’s unique three-dimensional electrical waveform instantly turn sharks away by causing unbearable spasms in these sensitive receptors.
And it's powered by a battery stored in a surfboard tail pad: can it be swapped between boards?
The FREEDOM+ Surf has been designed for the surfer with a big quiver. The removable power module is housed in the custom designed Ocean & Earth tail pad kicker, enabling you to move the power module easily between your boards and for recharging. The all important antenna electrodes have been designed into a sticker thin adhesive decal - only 600 microns thin - applied to the underside of the surfboard. With a weight of just 230 grams and a near zero drag, there is no impact on your surfing performance.
How long have you worked on this product for?
We have been working on innovations for surfing for a long time, with our first surf product, the SURF7, coming out in 2007. That was our 'Sony Walkman' version.
We initially investigated using the fins as electrodes, but found this difficult unless you owned the plug as well, and having to cut something into your board is badness.
We started the decal antenna innovation in 2015 with a grant from the Western Australia government. The design of the all new FREEDOM+ Surf is the result of collaboration with Ocean & Earth and two-time world surfing champion Tom Carroll. We are very confident we now have the 'iPOD' version, or certainly heading in the right direction. Anyone can install the new FREEDOM+ Surf on practically any surfboard.
Shark Shield will be a feature story on 60 Minutes. During the investigation what did they find?
How many people would conduct live white shark testing of a new product on national TV? I think that’s what I was asking myself in the months leading up to the testing with 60 Minutes! At the end of the day you just have to have confidence in your technology, confidence in the years of testing we've conducted, and the years of independent testing...along with a few beers to calm the nerves.
We had issues on the day - as with all testing. The main issue was getting enough weight on the board to simulate a human, to keep the electrodes underwater, which they need to be to conduct. We had no interactions with the active floats [with Shark Shield on], but plenty of interactions with the non-active floats [Shark Shield off]. We also found post-testing that our power output was lower than designed.
Yet without giving too much away, Mr Carroll lived up to his utterly fearless reputation by surfing alone protected by his FREEDOM+ Surf. Even with a shark coming to say hello…
On the 4th July Professor Shaun Collin will release a paper on the efficacy of electrical shark deterrents? What's his relationship to Shark Shield?
He heads The University of Western Australia’s Oceans Institute and the School of Animal Biology, his bio runs for about ten pages. A world renowned expert in his field, Collin has authored many scientific papers in the field.
Shaun led the research with Associate Professor Nathan Hart, and Dr. Ryan Kempster, with the research funded by the Western Australian Government over 2 1/2 years costing $680,000.
The research is independent with no relationship between the scientists, UWA, and Shark Shield.
It's hard for any technology to claim conclusively that they deter sharks, don't they all rely on an element of human faith? Faith in the technology, that is, not faith in the bearded bloke upstairs...
This statement may have been the case historically, however what the UWA peer reviewed research shows, and shows conclusively, is that Shark Shield does work. The technology without doubt reduces the risk - a 90% reduce is significant.
The risk of a shark encounter is so low it’s ridiculous that we can’t overcome our fears and doubts. Well, now if you want to go back to enjoying the ocean, you can take personal responsibility for removing the risk, you don’t have to have faith in the bearded bloke upstairs, the facts are the facts, Shark Shield significantly reduces the risk.
Comments
How might a bodyboarder make use of one of these... given that they lie on the tail of their boards, where the power module might live?
(no smart arse comments please)
It might fit on the front. Sticking it down might be a problem given the flex of a bodyboard. You could make something to hold it on using something like leash plugs.
funny how they wil not give100 percent guarantee against shark attack refer paul buckland coroners report and peter Clarkson coroners report both attacked and killed while wearing shark repellent shields with the findings that it will not stop hungry and exited sharks from attacking .purely feelgood product?
does any safety eqipment come with a 100 percent guarantee?
i always wear a full face helmet while riding a motorcyle. but it's not 100 percent guaraanteed to save my head from injury. it won't save me if a truck runs over my head (aka an excited and hungry shark). but that doesn't make a helmet a purely feelgood product -- a helmet will save my head from all or some injury if i come off and hit something at 20kms.
so the issue is whether this shark device will deter sharks who aren't hungry and excited and still might take a exploratory bite (and take off a hand -- as at bondi, or nose of your board --as at bronte). an example might be mick fanning at j-bay last year. that was not an excited and hungry shark that would not stop at anything. something deterred that shark from eating him. maybe a shark shield would help in those circumstances.
Hi Rustie,
Re the coroners reports you are referring. For Mr Clarkson and a quote from his boat captain, Mr Rodd. "Mr Clarkson would turn the Shark Shield off when he was on the bottom. Mr Rodd did not know whether Mr Clarkson had the Shark Shield turned on at the time." There is nothing mentioned in the coroners report about Shark Shield and there were more questions placed on foul play.
For Mr Buckland, the Coroner reported that, at the time of the attack, Mr Buckland had not been using the Shark POD unit in accordance with the instructions contained in the User Manual, thereby rendering the device ineffective. The Coroner went on to make a number of conclusions that were extremely positive for Shark Shield. He stated:
“... both commercial and recreational divers who dive in areas where they may encounter sharks should be encouraged to wear this equipment.” “I therefore recommend, pursuant to Section 25(2) of the Coroners Act, that commercial and recreational divers, when operating in waters where there is a risk of the presence of sharks, should wear a shark repellent device of the ‘Shark Pod’ or ‘Shark Shield’ type, provided that the equipment should be used in accordance with the manufacturers instructions, and should be turned on for the entire duration of time in the water.”
C. Huveneers testing in 2012 showed that the Shark Shield was very effective at deterring an attacking great whites ambushing a seal decoy. Presumably they were hungry and excited . Here's some video
Neither finding mentioned anything about Shark Shield not being effective therefore I hope this helps clear up your perceptions on this.
Look forward to seeing the research. The magnet pushes have been heavily promoting their product in Facebook and from what I have read it looks like a total scam. No amount of celebrity endorsement makes a product actually work. I tried to start some debate on their Facebook page but was promptly banned. I'm very uncomfortable with products that play on people's fear to make a quick profit.
https://www.choice.com.au/health-and-body/diet-and-fitness/surfing-and-s...
How long does the battery last with an effective output?
4-5 hours.
Maybe get a custom peabo and work with the manufacturer.You would think you could squeze one in a booger somewhere.....
The intention is admirable and the tech looks convincing/best-in-class. I just feel the cost and setup will be a barrier to mainstream uptake. $599USD buy-in and then add $99USD to each of your boards - all good and well if surfboards didn't snap easily. Especially considering some of the sharkiest spots in oz are also the most powerful.
I like it. Never really worried too much but with something as user friendly as this I'd consider. Would like to read research papers first though
All this new shark deterrent technology is interesting for sure and reduces the risk for the user but what about everybody else. Have they looked at what impact if any this sort of thing has on drawing sharks in initially. Yes up close they say it will upset their receptors and deter them but from a distance to a shark cruising the ocean would it not register as something interesting and worth checking out initially. It will be 90% not a problem for anyone on a board with this technology once they get close but what about everybody else in the line up do they suddenly find themselves more of a target for a curious shark. They said themselves in testing they had no interaction with active floats but plenty of interaction with non-active floats. Surely this cant be a good thing for surfers who for whatever reason choose not to use or cannot afford this tech.
Hey Redbeard,
It's been a common query and I asked Lindsay about it. He said they don't attract sharks...but then he's the CEO of the company. Apparently this topic is tested in the upcoming studies which will be released on July 4th. We'll post the reports on Swellnet.
I have read this too in the research papers where they did static and dynamic testing (dynamic where they tow a baited "seal" like buoy). All static tests there were more interactions, and almost all times they still took the bait with the device switched on.
There seems to be a big grey area on the dynamic testing, as they state in their papers, there were no records for when there was no interactions etc.
As surfers, we are static more than a dynamic object.. so in theory a shark will come to say hello a few times before figuring out they can still take a bite...
If there are new studies being done, i want to read them. I've bought the Sharkbanz/Modom leggie, does it work effectively.. well again research - very little. $250 v $600 + $100 every other board...
If Shark Shield can provide conclusive and non flawed research, I'll happily hand over the cash.
Hi Redbeard, sharks cannot sense electrical fields over long distance, not more than 0.5m. Sharks use several senses to detect prey - sound >1000m up to several kilometers, smell >100m, pressure <100m, vision <100m and lastly electrical perception <50cm to detect their prey. If a shark comes in to check you out, its most likely the vibrations from you splashing or your silhouette. It is not the electrical signals from your muscles, heart beat or a Shark Shield that will attract a shark.
Sharks also use the Ampullae of Lorenzini is also used for navigation using the earths magnetic fields. These are constantly available to a shark, and also to you if using a compass, so there is no need for long distance detection.
The protective field size on a Shark Shield is a 4-5m radius from the antenna. So if a shark is cruising toward anyone with a Shark Shield, then at a distance of 4-5m + 50cm it will feel the field, causing spasms in its Ampullae of Lorenzini, causing it to turn away.
The 2 most recent independent studies (C. Huveneers, 2012, Flinders University, & S. Collin, 2016, University of Western Australia, Oceans Institute) both tested whether the Shark Shield specifically attracted sharks and it does not attract sharks.
Hope this helps clear this up.
Well answered Mr Willson.
Yeah good call redbead
I raised the same issue with the earlier product and they seemed very sure of themselves in terms of it not attracting sharks. I would think at most crowded spots the type of system in use at J-Bay, provided that it works, would be more cost effective and safer.
Rustie - I don't think the Peter Clarkson coroner's report is of much value in assessing shark shield effectiveness as the coroner basically said that the shark attack was a fabricated story by Howard Rodd. Peter was a man of the sea and did use the shark shield, he had testimonials on their website for many years. I always use one when diving here in SA , they must work because I've never seen a shark! SARDI did plenty of independent testing of shark shields at the Neptunes and they don't stop hungry pointers. The only effective shark repellent is the powerhead but they are not politically correct devices these days.
Hi Nat,
On the SARDI testing by Charlie Huveneers in 2012, it was actually very positive. The dynamic seal decoy testing showed the Shark Shield to be vert effective. 16 breaches on the seal decoy with it turned off, and 0 (zero) breaches with the Shark Shield turned on. Here's some video footage
The SARDI static bait test did not look as favorable, without knowing more about the test itself. This was due to the test setup, where the bait was placed on the very edge of the Shark Shield protective field. This allowed the sharks to eventually take the bait, but it took twice as long compared to the unit being turned off. So the sharks would circle the bait, finding the weakest field and eventually take the bait.
A similar static bait test by Smit & Peddemors, 2003, but with the bait in the center of the protective field, similar to the FREEDOM+ Surf, had a 100% success rate. Not one great white could take the bait. Here's an explanation of the testing
Shark Shield will never claim 100% of the time that the Shark Shield will stop a shark, but neither will a seat belt or airbag manufacturer. Are you safer to wear a seat belt and have airbags in your car - sure.
I live in Florida where powerheads are still used. They are not so effective because in more than 60% of sharks bites, the person didn't eve see the shark coming. Many spearfishers, including commercial, are using Shark Shield and see it work every single day bull sharks here are constantly fighting for their catch.
Hope this helps explain the SARDI results a little better.
Lucky Leash legrope - $40US
More magnetic wank.
paddle out with you new shark shield in a crowded lineup , with a doggy bag of blood and see what happens!!
Well, if the supplier's information is correct, statistically, 9 out of 10 other surfers in the crowded lineup would be attacked for every time the shark(s) had a go at you, but you might be unlucky and your 10% probability could come up first.
Like nat,i also use a sharksheild freedom 7..its about 10 years old..ive had it turn away a bull and a bronzey,but as for gw's they are a ambush preditor..when there moving at mach 10 in your direction there gunna be hard to stop..ill be keen to check out the new version for my 6'4 thats for sure....
Check out this video
The design of the new model's terminals and battery pack are a big improvement on the old model. It's definitely worth a closer inspection, and if it can be easily transferred between boards it might be good insurance. I've wondered too about the claims that these devices are attractors at longer distances. Even if those claims aren't true, I suppose the presence of the devices on some boards in the lineup would increase the risk of attack for the riders that don't have one on their board, once a shark enters that spot, simply because the number of potential targets is reduced and therefore your odds go down. It's a bit of a grim outlook on it, I know.
I can't remember where I heard or read it, but one of the device manufacturers said that the field around these electric deterrent devices is for all intents and purposes undetectable outside of a few metre radius from it, and that shark's sensory detection of that type of field is short range. Meaning that it doesn't attract sharks to an area. If a shark can detect the field then it's already at close range and can already see you.
I don't understand how anyone can say that one guy wearing a shark deterrent puts others in the line-up at risk. The shark would be there anyway. What if that guy with the deterrent wasn't out there at all, does that still increase the risk to others by way of increased odds?
Chin,
My point was that "once a shark enters the area" (regardless of what attracted it there) any non-shield user's risk of attack simply increases because the shield users are undesirable targets. Another way of saying it is if I were surfing at a well known shark haunt and the other riders were using shields I'd be motivated to use one too, because if I didn't it would be the same as surfing there on your own, which is the point you made in your comment. A rider using a shield is the same as a rider not being there.
Further to what Chin is saying I read that a shark can detect a human heartbeat within the water at so many metres (I can't recall). But a bigger attractant than Shark Sheilds electrical field I guess would be the unnatural flailing around of surfers trying to catch waves reminiscent of a wounded seal. That I would assume would excite a shark more than anything.
Thank you all for your comments, we are super excited about our new product getting people back to enjoying surfing! Couple of facts to clarify;
There has only ever been one fatality with a person wearing a Shark Shield in 2002, with the coroner report finding the user was not wearing the SharkPOD model correctly, with the coroner further recommending more people use Shark Shield. There was no finding with Peter Clarkson, there were more questions relating to why the skipper called his lawyer before the police, I believe this was the second diver lost on his watch.
Many years ago I was an electrician, and I've also been a CEO of another safety business. I can assure you there is not a safety product on the planet that removes 100% of risk, doesn't matter if its steel cap boots, protective glasses, seat belts etc. If an Occupational Health & Safety Officer was told he could remove 90% of risk from an activity, I'm confident the'd take the offer. You could remove the risk by not going in the water, but with the release of the Sharknado movies this is clearly now not an option either..............
Last time Shark Shield was on this forum, for days the conversation continued on the myth that Shark Shield attracts sharks. I only have an electrical / electronic educational background so can only comment with authority on the technology and its inability to transmit any distance underwater. With respect to animal biology, both major research papers, including the extensive independent 2.5 year study by the UWA being released on the 4th July, concluded that there was zero evidence that Shark Shield attracted sharks. Professor Shaun Collin's bio runs for ten pages, so please believe Shaun over what the chap with the beer glasses at the Settlers Tavern says.
The research and testing will be on Sixty Minutes this Sunday 3rd July,(the trailer is on our Facebook) and hopefully you'll get a lot of other questions answered on the proven effectiveness of Shark Shield during this, thank you all for your support.
Best research I have seen is mates of mine in South Africa who have been using your "Sony Walkman" version for years now. They regularly surf a place called "Breezy Point" in the Transkei and for those in the know this place is as heavy as it gets shark wise. Call them crash test dummies if you want but they have never had an incident to date. Might be they're just lucky!!!
Where is the paper being published? If it is online can you post a link when it appears? If not a journal reference is fine.
I spent hours searching the net last night reading about sharks electroreception etc to try and find an answer to my own question but I just ended up with more questions. I look forward to reading the research papers from UWA despite scientists best intentions it seems we still know very little about sharks especially large sharks like the great white which cannot be studied in controlled conditions in captivity. I do not doubt its effectiveness as a deterrent you have obviously done the work and the science is sound in that regards. You would not have got this far and be product showcasing on Sixty Minutes etc if it did not work. It will be no doubt a great relief and peace of mind to some surfers to have this on their board. Sharksheild I just have one question while you are here on the forum perhaps you could answer for me. I am sure you have measured it in testing but in regards to the tech and its inability to transmit any distance underwater at what distance from the device in seawater does the electrical field become undetectable?
6m is the max distance that the Shark Shield is able to be physically detected by any scientific instrument.
Field strength would be proportional to voltage and according to this paper frequency also. Also the conductivity of the water itself will have an effect on field strength i.e higher conductivity = larger electric field. This would be different depending on location as sailinity levels and molecular structure of the water will be different from place to place i.e surfing a river mouth with large amounts of fresh runoff and organic matter will reduce the strength of the field.
As for attracting sharks imo the field strengh would dissipate very rapidly and if u read the first couple of pages you will see the distances talked about are only very short (under 10m)
which leads me to believe that the output of this device (unknown but very likely under 14 volts) would not be enough to attract sharks from a a large distance.
http://www.dtic.mil/dtic/tr/fulltext/u2/a578944.pdf
Ok, hope this helps rather than confuse;
The effectiveness of an electrical shark deterrent is dependent on the electrical field generated. The electrical field generated is dependent on a number of factors, these include the electrical power output, the size of the electrodes, the distance apart, the physical electrical wave shape and frequency.
Whilst software modeling is a good indicator of performance, the only way to confirm is to conduct in-water testing using electronic test equipment to take physical measurements, then compare these to what is known through historical independent scientific testing to be effective.
For example the FREEDOM7 and FREEDOM+ have a volts per square meter measurement of ~6.0 volts/ square meter at 0.5 meters from the electrode, and ~2.0 volts / square meter at 1.0 meter from the electrode. As you can see the further away from the electrode the lower the e-field power. At 2.0 meters from the electrode the power is ~0.5 volts / square meter.
Our software modeling, in-water testing, and supported by research conducted by the South African National Space agency, showed that at around 5-6 meters from the electrodes there is no electrical field detectable, as in zero.
Shark Shield is 10x the power output of any other electrical deterrents on the market, we have measured all of them. So claims of protective fields 20 meters are completely false, and when you watch our video's and see the UWA research video, they get dam close, as in sometimes less than a meter before they are deterred, but they are turned away!
^^^^in regards the last paragraph - have you tested the latest rpela device? They claim to be the same power as shark shield. Link here https://www.rpela.com
Also 1 question. Is it possible to make the power unit smaller? Good idea putting it in kicker but it looks quite bulky to me.
hi scottie thanks for your comments. just finished watching national geo doco on youtube SHARK ATTACK VIDEO -AUSTRALIAS DEADLIEST WHITE SHARK COAST 2016 at the 29.30 minute mark it shows UWA scientists field testing shark shield in the field. Three main points were discovered a)sharkshield did repell sharks b)sharkshield does not work on all attacking sharks c)after sharkshield has been activated for awhile sharks become immune to its affects and readily attack baits with activated sharkshields attached. Still some way to go. I like all users of the ocean appreciate the work these guys are doing.
Hey Rustie, thanks, I hadn't yet seen this. It's interesting because some of the footage being shown is from C. Huveneers testing in 2012 and with the Shark Shield turned OFF, yet they are portraying that the sharks can get close to the Shark Shield. Totally misleading by National Geographic and very poor production given this fact. Here's the footage
We are yet to see the UWA white paper which is being released on the 4th July. Overall Shaun Collin the lead scientist has given very positive feedback.
Another interesting fact is that the KwaZulu-Natal Sharks Board in South Africa, who are world leading scientists in shark biology, and the original developers of the Shark Shield field waveform 20 years ago, have now just developed an electrical beach barrier to replace beach nets. It has just recently been proven to deter sharks after several years of testing in South Africa . If sharks were able to learn the field, then I would think that this technology would not work effectively? http://www.shark.co.za/Pages/SharkRepellentTechnology
We know that Shark Shield doesn't work on all sharks. However it works on predatory sharks such as whites, bulls tigers, oceanic white tip. Less predatory sharks like grey nurse and wobbegong have less well developed ampullae of lorenzini and are less affected by the field. They also typically aren't going to bite.
At the end of the day, a Shark Shield is designed as a safety device to limit unwanted human and shark interruptions. If you see a shark while surfing, you get out of the water. The Shark Shield is the only device that will give you the time to do that. We have a testimonial of a Sydney surfer doing just that, after seeing a supposed great white, his three mates stuck very close to him while calmly paddling back in, as they were not wearing Shark Shield's. :-)
Hi Scott, thanks for feedback see what you mean about dodgy editing. On your point of if sharks are able to learn a field then the technology would not work effectively. As you would have seen on that doco UWA scientists have proven sharks are able to somehow detach themselves from the affect of the field if exposed to it for a period of time proven fact not dodgy editing. this is openly stated on the doco by scientists working for UWA on the testing of sharkshield as an issue of concern. would hate to be pinned 20 mt down against ledge by white wondering at each pass it makes if this is the one my sharkshield loses its effect. Intersested to see how successful they were in dealing with this issue. white paper should reveal all.
Enough stuff,were drowning in a sea of skeghettio! So simple is sea song- breathe feel transform into seacreatures whilst chalming your wave. Hueys hydragliffs are decoded thru waveface by brainwashed bodybasherz,dolphin and turtles. Hueys sea song(News of the day,if you like) is roughly chalmed as follows.... Crowded line-up will soon become metroskeg disco...500 shark radios all turned up to 11,crosswired outta tune frying the brains of last legged rundown inshore sea life spelling an end to whale netting season. Hooroo!from you know who and Huey too!..Dear surf god Kelly,please make it rain waves for our friends in Seaworld pet porpoise pool.
60 minutes...pfft....nothing new there , that was a near perfect day at Neptune ,not many days a year like that...sunny, windless, clear water,no footage from above -test footage was crap.
Did he say a electronic field 6m x 4m around the wearer ?
yeah bit ordinary alright would have thought they had plenty of opportunities to test their design properly but was all a bit half baked.......only half proven.....
I really like the idea however thought yeah it could've be shown a little more clearly. That one time the shark ploughed straight through it……I thought 'yeah no thanks'……..all the said was 'maybe they needed more weight on it'………well why didn't they test this and show us? I'm sure they have but as mentioned an above view would'e been good to see, the shark seemed to get pretty bloody close for my liking.
Here is the link to the UWA Research Paper on the Shark Shield testing, and I've pasted below the abstract / summary.
http://journals.plos.org/plosone/article?id=info%3Adoi%2F10.1371%2Fjourn...
How Close is too Close? The Effect of a Non-Lethal Electric Shark Deterrent on White Shark Behaviour
Abstract:
Sharks play a vital role in the health of marine ecosystems, but the potential threat that sharks pose to humans is a reminder of our vulnerability when entering the ocean. Personal shark deterrents are being marketed as the solution to mitigate the threat that sharks pose. However, the effectiveness claims of many personal deterrents are based on our knowledge of shark sensory biology rather than robust testing of the devices themselves, as most have not been subjected to independent scientific studies. Therefore, there is a clear need for thorough testing of commercially available shark deterrents to provide the public with recommendations of their effectiveness. Using a modified stereo-camera system, we quantified behavioural interactions between white sharks (Carcharodon carcharias) and a baited target in the presence of a commercially available, personal electric shark deterrent (Shark Shield Freedom7™). The stereo-camera system enabled an accurate assessment of the behavioural responses of C. carcharias when encountering a non-lethal electric field many times stronger than what they would naturally experience. Upon their first observed encounter, all C. carcharias were repelled at a mean (± std. error) proximity of 131 (± 10.3) cm, which corresponded to a mean voltage gradient of 9.7 (± 0.9) V/m. With each subsequent encounter, their proximity decreased by an average of 11.6 cm, which corresponded to an increase in tolerance to the electric field by an average of 2.6 (± 0.5) V/m per encounter. Despite the increase in tolerance, sharks continued to be deterred from interacting for the duration of each trial when in the presence of an active Shark Shield™. Furthermore, the findings provide no support to the theory that electric deterrents attract sharks. The results of this study provide quantitative evidence of the effectiveness of a non-lethal electric shark deterrent, its influence on the behaviour of C. carcharias, and an accurate method for testing other shark deterrent technologies.
So has anyone tried the product yet? (Shark shield surf). Very keen to hear feedback especially in regards to its impact on board performance.