Shark Deterrent?:-)

4 months ago
Reply
Register to post, see what you've read, and subscribe to topics.
Johndesu
Johndesu
NSW
574 posts
NSW, 574 posts
20 Jun 2026 10:28am
Just wondering if anyone has or has used an electronic shark deterrent like Shark Sheild or Rpela etc? & how is it etc?:-)
ptsf1111
ptsf1111
WA
618 posts
WA, 618 posts
20 Jun 2026 9:17am
The ones that reply here might say they work. The ones that got eaten can't reply here anymore 😉

Jokes aside, I think there is no evidence that these work, at least at the scale of human-wearable devices (manufacturers obviously want you to believe otherwise). It's probably also difficult to prove they don't work, so these can still be sold and I'm sceptical about these manufacterer's claims.

Can't answer your question as I'm not wearing these, so apologies for the spam. I'm sure someone will disagree with me. 🤣
Johndesu
Johndesu
NSW
574 posts
NSW, 574 posts
20 Jun 2026 11:41am
No worries I know but I am interested in the ones made for surfers that attach to your board & use a lithium battery to create a electromagnetic field that you can feel etc:-)
ptsf1111
ptsf1111
WA
618 posts
WA, 618 posts
20 Jun 2026 4:45pm
Yup, depending on which query you put in Google, you'll either find resources that tell you it deters sharks, or others stating it will actually attract them (and put others at a heightened risk).

Anyway, you know my opinion now so honestly curious what others think as it's hard to find reliable info on these things.
colas
colas
5428 posts
5428 posts
21 Jun 2026 2:07pm
ptsf1111 said..
Yup, depending on which query you put in Google, you'll either find resources that tell you it deters sharks, or others stating it will actually attract them (and put others at a heightened risk).


Importantly, there are studies, but their results depend greatly on the shark species. Some sharks do not even use electric currents to hunt...

"The threshold for an electrical field to repel a shark can vary by species but ranges from about 3 V/m (to deter bull sharks) to 18.5 V/m (to deter scalloped hammerheads), with some species requiring even higher field strengths.
The key challenge, however, is to create an electric field that extends far enough into the surrounding water. Generating long-range electric fields in seawater is inherently difficult because seawater is highly conductive. The electric current disperses rapidly through the surrounding medium, causing a voltage gradient that drops sharply with distance."

spectrum.ieee.org/electric-shark-repellent

Or: " The effectiveness of the deterrents was variable, with the Freedom+ Surf affecting shark behaviour the most and reducing the percentage of bait taken from 96% (relative to the control board) to 40%. The mean distance of sharks to the board increased from 1.6 ± 0.1 m (control board) to 2.6 ± 0.1 m when the Freedom Surf+ was active. The other deterrents had limited or no measureable effect on white shark behavour. "

pmc.ncbi.nlm.nih.gov/articles/PMC6120439/

Also, beware of the studies that select specific species because they respond well to the electric devices... They are not wrong, but their results may apply differently to other species.
"The bonnethead shark, Sphyrna tiburo L. 1758, was selected as the study species due to ease of acquisition and husbandry coupled with their documented use of the electrosensory system when hunting "


onlinelibrary.wiley.com/doi/10.1111/jfb.70220
Johndesu
Johndesu
NSW
574 posts
NSW, 574 posts
22 Jun 2026 10:35pm
colas said..

ptsf1111 said..
Yup, depending on which query you put in Google, you'll either find resources that tell you it deters sharks, or others stating it will actually attract them (and put others at a heightened risk).



Importantly, there are studies, but their results depend greatly on the shark species. Some sharks do not even use electric currents to hunt...

"The threshold for an electrical field to repel a shark can vary by species but ranges from about 3 V/m (to deter bull sharks) to 18.5 V/m (to deter scalloped hammerheads), with some species requiring even higher field strengths.
The key challenge, however, is to create an electric field that extends far enough into the surrounding water. Generating long-range electric fields in seawater is inherently difficult because seawater is highly conductive. The electric current disperses rapidly through the surrounding medium, causing a voltage gradient that drops sharply with distance."

spectrum.ieee.org/electric-shark-repellent

Or: " The effectiveness of the deterrents was variable, with the Freedom+ Surf affecting shark behaviour the most and reducing the percentage of bait taken from 96% (relative to the control board) to 40%. The mean distance of sharks to the board increased from 1.6 ± 0.1 m (control board) to 2.6 ± 0.1 m when the Freedom Surf+ was active. The other deterrents had limited or no measureable effect on white shark behavour. "

pmc.ncbi.nlm.nih.gov/articles/PMC6120439/

Also, beware of the studies that select specific species because they respond well to the electric devices... They are not wrong, but their results may apply differently to other species.
"The bonnethead shark, Sphyrna tiburo L. 1758, was selected as the study species due to ease of acquisition and husbandry coupled with their documented use of the electrosensory system when hunting "


onlinelibrary.wiley.com/doi/10.1111/jfb.70220


Yeah thanks colas I have being doing a lot of research recently also & I am maybe just going to just go with the Shark Eyes stickers & a magnet for now mainly because it is alot easier & simple & I do sup foiling on a Foil Drive Assist anyway:-)
drc13
drc13
NSW
189 posts
NSW, 189 posts
24 Jun 2026 10:16am
At the depth and speed they can hit you from beneath with absolutely no warning, not much short of a cage is going to help (a 2 tonne shark with momentum isn't stopping because of some eye stickers or small magnets)

I wish this wasn't the case I'd be willing to purchase something myself but for now it's just a risk we have to take to be in the ocean.
thuffam
thuffam
QLD
78 posts
QLD, 78 posts
25 Oct 2026 2:02pm
My experience is certainly that foil assist devices attract sharks.... I was on the lake at Kawana Island (not lake kawana), on the Sunshine Coast, and learning to use my DIY foil assist.. doing quite well but falling off a few times... at one point I heard a splash behind me.. when I turned I saw nothing but white water then I fell off (not concentrating).. when I kicked my legs out behind me to lurch forward toward my board, my foot landed squarely on the back of something large.... large enough I could push myself off from it (I am 80kg) and the feeling on my foot was something the circumference of a persons back (because my immediate thought was someone was swimming beneath me). Needless to say I zoomed to shore and never put a foot in that pond again. This was only 20m from the shore right in front of the cafe.
So when I'm using it in the ocean.. I am hyper vigilant... and not that fussed about the bay at Mooloolaba which is mostly murky and we know has bulls.

I did read recently that the fishing charter boats have found that sharks have learned to follow the motor sounds.

So my take away is that I guess being quiet helps.



Please Register, or first...
Topics Subscribe Reply