How do sharks respond to strobes and flashes in their face?

[DazedAndConfuzed]

aren't sharks sensitive to electric fields which the high voltage capacitors in the strobes emit quite a bit of?

 

[Diver0001]

Personnally I will dive with all sharks except the OWT which I consider the most dangerous animal in the water.

I've dived with quite a few smaller ones and they don't come across as particularly aggressive to me at the 1 metre range. I had a really big one, probably a 3 metre long monster scare the bejezus out of me once though. It came at me and my buddy from out of the blue.... back arched, pectoral fins down swimming at high speed in B-line straight at us. My first thought was "wow" and my second thought was "holy f.....k". It turned away at the last second instead of plowing into us but by that time I was just about pissing myself.

When they get to be that size I wouldn't even want to get close enough to take a picture.

R..

 

[bowlofpetunias]

Big thing is to leave them a clear path of "escape" if they do spook.. if you aren't in their way they are not likely to bowl you over. I have seen them startle from a strobe too close and accelerated very quickly to get away!

 

[billgraham]

I've done a lot of shark photography in North Carolina and the problem I experienced is there are so many sharks and they are so curious you can't keep track of where they are, and you get bumped from behind. I did a shark dive in Fiji and there was a really aggressive silvertip that wanted to eat my red SB 104. I was told by the Fijian divemasters that they are attracted to red and yellow so I'd avoid those colors if possible.

 

[Searcaigh]

I have photographed Sand Tigers in S. Africa without losing a strobe or camera, although a few shots right in their face did startle the sharks at first, and me too for that matter when they suddenly veered off.

 

[eddyunderwater]

The sound of the charging of the strobe capacitor between shots is what I have been told (from good sources) is the primary issue.

Yes as D-Diver said, that does happen, for the sharks hearing is excellent plus their sensory glands [ampullae of lorenzini] and they do react a little to the 'weeeeeiii' noise from the charging of a flash/strobe, when I work/shoot with a pack of sharks numbering in the dozens.. a little nudge from the nose/melon and a 'sniffing' action left and right and they know it's not food.

However I have had many a video camera and all but one of them have attracted the sharks. When the mechanism is running, the mechanical noise during the turnover [especially those still shooting on HDV cassette like a Sony Z1U] does cause some interest.
However the attraction is minimal and if you were me you would be very grateful - because that 'close encounter' = great shooting!
Recently shooting for a European production company, I noticed that our sharks [Caribbean Reefs] were interested in my metal body video housing more than another guy's plastic one, this may have been coincidence, but maybe the noise carried easier through the metal than the plastic acting as an insulator. We both had similar cameras too.

Needless to say - Tigers are way more curious, Caribbean Reefs are less. Lemons are in between- and I have not been with Whites yet, but whatever your shark, there is a curiosity factor slightly more in some or less in others, in each species. Tigers have lifted cameras out of people hands and 'stolen' them for a time.

Now if you are talking Octopus, they absolutely adore the strobe heat, light, and stick to your strobe for ever if you let them!
All the best
Eddy

 

[miked]

Not sure what attracted it, but..
A few years ago, during a safety stop, where I had already turned off my camera, a few sharks came into view-swimming past us, basically ignoring the divers. Deciding to take a picture, I switched on my camera. As soon as I did that, the nearest shark (small-a 4 footer), did a snap turn, and came right at/towards my camera (mouth closed, thank God). I used the camera to assist the shark down and past me, and all was okay.
My guess is that it was the sudden "on" of the electric field from the camera.

 

[smellzlikefish]

I wouldn't worry so much about the more docile sand tigers, but some of the more tightly-wound sharks can act aggressively. I usually enter the water with the strobes turned off and only start flashing only after I have gotten a good feel for how the animals are acting.

I had one especially curious oceanic whitetip follow a metal clip down to the depths. The reaction of metal in seawater produces a small electrical signal that they can pick up on. When the shark came back, it wouldn't leave me alone and eventually took a snap at my strobe. That was my cue to leave.

There are really two potential stimuli emitted by a strobe. The bright flash can startle the animal, as was the case with a gray reef shark and Mike DeGruy. Then there is the electrical discharge picked up by their ampullae of lorenzini and the electric whining noise of the strobe charging. That was how I got into a spot of trouble.

edit: I just remembered a large tiger shark that I encountered off Kona last year that was swimming away until my flash went off. The animal turned suddenly and charged me turning within a couple of feet of me. Again, different animal than a sand-tiger altogether, but still reason for caution.

 

[Max Speed]

All you need to know about Oceanic White Tips, Electronic Noise and eating you. Pretty ugly.
Shark Attack! | Divers' Blogs

 

[DazedAndConfuzed]

Damn, I should have made a jacket out of strobes when heading down to galapagos. those hammerheads need all the electric field/wizzing sound that I can give in order for them to get within 30 ft of me.