Electric ocean anti-shark defense?

[Blakelyneal]

can anybody tell me how to build a way to pass current through salt water at command strong enough to repel sharks?

 

basically the same idea behind the shark shield except homemade and not 500+ dollars haha

 

plus it isnt always effective, and for that I can make my own and not be out anything more

 

any ideas?

[Moontanman]

I actually designed something similar to that 30 or so years ago, sadly I never developed it but it would seem someone else has perfected it.

 

http://www.shark.co.za/repel.htm

[Mr Skeptic]

Yes, because untested homemade products that your life depend on are such a good idea. Or did you plan on getting a shark to test this on?

[Moontanman]

I scuba dived for many years, when I first started I was "concerned" with the problem of sharks, but after many years and many hours of dive time the sight of a shark is more of thrill than a scare. I think I've seen a shark maybe a dozen times over the years, good training and safety habits will keep you alive far better than all the bang sticks and shark repellents in the world. Sharks almost always ignore divers, it's why dive charters to see sharks have to attract them, if sharks were looking to eat people scuba diving would be suicide.

[Externet]

Hi.

Diver too. With some very scary incidents on records; am taking a couple of actions for the next season.

 

1.- This animal:

 

--->http://www.dealextreme.com/details.dx/sku.1997

 

It is NOT A TOY ! Waterproofed, will permanently blind any menacing shark in less than a second, from a safe distance. Must be used with care.

 

2.- To try if protects the rear end, attaching magnets to the fin tips :

 

--->http://www.wired.com/gadgets/miscellaneous/news/2007/05/sharkmagnets

 

If it does not work, well. I tried. I do think that motion of a magnetic field in a very conductive media as seawater, has to generate currents.

 

- I will not discuss the humane or not side.

There is gadgets in the market that attach to the diver and emit voltage pulses, supposed to work. Very pricey for peanuts technology.

 

Always wondered if a piezoelectric lighter, properly waterproofed with the terminals at the tip of a pole can give a shock to its nearby zone, (includes the diver) when triggered.

[Moontanman]

Hi.

Diver too. With some very scary incidents on records; am taking a couple of actions for the next season.

 

1.- This animal:

 

--->http://www.dealextreme.com/details.dx/sku.1997

 

It is NOT A TOY ! Waterproofed, will permanently blind any menacing shark in less than a second, from a safe distance. Must be used with care.

 

 

This is totally untested at best and totally bogus at worst, I doubt a shark would be impressed by a laser underwater unless it was shown directly in it's eyes up close, even then i am skeptical to say the least.

 

 

2.- To try if protects the rear end, attaching magnets to the fin tips :

 

--->http://www.wired.com/gadgets/miscellaneous/news/2007/05/sharkmagnets

 

If it does not work, well. I tried. I do think that motion of a magnetic field in a very conductive media as seawater, has to generate currents.

 

- I will not discuss the humane or not side.

There is gadgets in the market that attach to the diver and emit voltage pulses, supposed to work. Very pricey for peanuts technology.

 

Always wondered if a piezoelectric lighter, properly waterproofed with the terminals at the tip of a pole can give a shock to its nearby zone, (includes the diver) when triggered.

 

 

The link says this is not a viable way to prevent a shark attack,

 

Divers and swimmers may thrill to the idea of shark safeguards. However, before you rush out to buy neodymium magnets to create your own shark-repelling gear, Herrmann cautions that the magnets appear to have an effective range of only 10 inches. Also, you'd need to align the magnetic poles outward and keep the magnets from clicking together, and once you had the necessary 10 to 20 pounds of magnets all over your body, you'd sink. So, at a cost of about $5 a magnet, you could theoretically turn yourself into a $400 shark-safe anchor at the bottom of the sea.

 

 

 

Read More http://www.wired.com/gadgets/miscellaneous/news/2007/05/sharkmagnets#ixzz0hMyGjL0w

[Externet]

..."This is totally untested at best and totally bogus at worst, I doubt a shark would be impressed by a laser underwater unless it was shown directly in it's eyes up close, even then i am skeptical to say the least."...

 

Of course that has to be aimed at the eye, one by one. What were you expecting ?

 

A poorly written site from someone making a living with a wimpy 5 milliwatt one:

 

--->http://www.airbuddy.com/id47.htm

 

The only sure thing is I do not want such laser aimed at my eyes, underwater or above water.

 

Better ask an eye doctor...

[Moontanman]

..."This is totally untested at best and totally bogus at worst, I doubt a shark would be impressed by a laser underwater unless it was shown directly in it's eyes up close, even then i am skeptical to say the least."...

 

Of course that has to be aimed at the eye, one by one. What were you expecting ?

 

A poorly written site from someone making a living with a wimpy 5 milliwatt one:

 

--->http://www.airbuddy.com/id47.htm

 

The only sure thing is I do not want such laser aimed at my eyes, underwater or above water.

 

Better ask an eye doctor...

 

Considering that sharks do not depend on their eyesight to a great extent and that they have a opaque membrane that covers their eyes automatically when they bite and that many shark attacks occur in water that is somewhat less than clear (even in black water) I think you might just piss him off with the laser.

[Externet]

Considering that sharks do not depend on their eyesight to a great extent and that they have a opaque membrane that covers their eyes automatically when they bite and that many shark attacks occur in water that is somewhat less than clear (even in black water) I think you might just piss him off with the laser.

 

Sharks do not depend on their eyesight to a great extent ? Where did you get that from ?

 

..."I think you might just piss him off with the laser"... How can you tell such ? Nobody knows !

 

When they bite who cares if their opaque membrane is on. It's too late for laser or bangstick !

 

This is just for 5mW red wavelenght; not 200mW class IIIb green without infrared blocking :

 

http://www.scientificamerican.com/article.cfm?id=can-a-pocket-laser-damage

[Moontanman]

Sharks do not depend on their eyesight to a great extent ? Where did you get that from ?

 

 

I guess the whole sharks sense of smell and them feeding at night kinda tipped me off, a blind shark is just as dangerous as one that can see. A great many experiments that covered sharks eyes up with opaque disks showed they can feed quite effectively when totally blind.

 

..."I think you might just piss him off with the laser"... How can you tell such ? Nobody knows !

 

Give it a whirl, maybe he will like it.

 

When they bite who cares if their opaque membrane is on. It's too late for laser or bangstick !

 

So you think you're gonna be able to target an attacking sharks eyes? I'd rather have a bang stick or better yet just not attract the shark to start with.

[Externet]

No, I would not target an attacking shark eyes. I would long before that moment by caution sense.

 

--->http://www.sharksavers.org/en/education/shark-myths/424-myth-sharks-have-poor-vision.html

 

Lucky you that have not experienced scary dangerous situations. I have nothing to lose by carrying in a dive whatever else can work as defense. Has to be better than only my 357 bangstick.

[Moontanman]

No, I would not target an attacking shark eyes. I would long before that moment by caution sense.

 

--->http://www.sharksavers.org/en/education/shark-myths/424-myth-sharks-have-poor-vision.html

 

Lucky you that have not experienced scary dangerous situations. I have nothing to lose by carrying in a dive whatever else can work as defense. Has to be better than only my 357 bangstick.

 

A shark is aware of you long before you are aware of him, in pitch darkness with zero visibility he knows where you are, he can sense the electrical emissions of your heart beat. I never said sharks had poor eyesight, I said they can feed with out their eyesight very effectively.

 

I would advise you to avoid situations where sharks would be likely to attack, don't drag dead fish around with you, stay away from areas where big sharks are known to feed, stay out of poor visibility water conditions (I know thats a little unreasonable, I like to night dive) if the water is clear enough for you to see the shark he will most likely avoid you, most shark attacks occur in water with poor visibility where the shark cannot get a good idea of what you are or how big you are.

 

If the shark is big enough to just come out of no where and bite you in half your bang stick is not going to help you, a laser is not going to help you, just not being there is about the only real defense.

 

BTW, you are just stirring up a tempest in a tea pot, how many divers a year are really attacked by sharks? you almost as likely to be hit by a meteorite.

Edited March 6, 2010 by Moontanman

[Blakelyneal]

well see, I am not too afraid of a shark attack when scuba diving only when I am snorkeling in the ocean not being able to see my surroundings all the time due to the fact I have to surface. I want a last ditch effort that will make the animal decide not to eat me if I get put in the situation.

 

Know what I mean?

[Externet]

Yep.

 

Not much confirmed proven data and tests performed to suggest how much voltage, duty cycle and pulse cadence works better with the least uncomfort to the diver in seawater. Existing gadgets may be too influenced by marketing to believe their performance.

 

Just try bursts of DC, AC, at varied voltages with plain sorrounding fish to learn their reaction. A shark should at least react similarly.

http://www.newscientist.com/article/mg13217923.800-technology-protecting-bathers-with-a-short-shark-shock.html

 

You are mostly on your own to evaluate whatever you build. Check for DC to DC converters, inverter circuits on the net, impermeabilize them and try. A disposable camera flash can be a starting point, can make up to 350V.

Come back with findings !

 

The kitchen piezoelectric lighter has to produce a shock. A magnet on each fin tip, don't know.

I know a ticking watch will attract them.

 

Electricity, fresh water and fish mix is surprising:

 

http://www.youtube.com/watch?v=FIGBHZFeNgo&feature=related

Edited March 6, 2010 by Externet