I read somewhere that they are sensitive to the low frequencies..
here's a mythbusters account of divers using flashlights..
During a nighttime dive, flashlights will attract sharks.
confirmed
This myth is based on the idea that the electromagnetic field created by flashlights may attract sharks. The Mythbusters first performed a control dive to see how many sharks appeared at night when they dove without flashlights. When they tried diving with flashlights, significantly more sharks appeared in a shorter amount of time and the sharks behaved more aggressively toward the flashlights.
Diver_Down said:
MT Pockets said:
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Sharks can sense the electromagnetic field of you and your detectors..
it's not wise to enter the water with a Metal Detector..
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I would be very interested in reading published studies on the effects of EMFs, frequency, and whether it is proven to attract or deter sharks. I am aware of their biology and the the ability to detect electromagnetic pulses with the the Amupullae of Lorenzini. I would like to know of what research has been done with varying frequencies with regards to attraction and avoidance. There used to be a product called Shark Pod, but the technology has since been ceded to Shark Shield.
http://www.sharkshield.com/Content/FAQ/