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> > Again no disrespect to your opinion, Rich, but I need more more than a
> > tidbit to make an informed decision about dragging my scooter to the shore
> > in N.  Calif the next time I go.
> 
> I would certainly hope that you wouldn't base any serious decisions on a 
> single tidbit.  It took dozens of tidbits for me to start leaning in one
> direction on the shark-scooter issue.


Some hard data might be obtained from the results of a test of an electronic 
shark net by researchers in South Africa. I think it was in Durban that they 
replaced a portion of a standard shark net protecting a beach with an
electronic 
shark repulsion system.

The developers figured that if stories of sharks being attracted by electric 
fields were true, then possibly a field could be generated that would annoy the 
sharks and repel them.

Rich may know more details about this.

It was not a simple cattle prod approach because that would take too much
power. 
The TV video report I saw showed researchers dropping an antenna wire in a tank 
with a great white. They tried various frequencies until they found some that 
seemed to annoy the shark. They then put food in the water and were able to 
drive the shark away from the food when they turned the transmitter on.

The idea was to replace the nets that are expensive and get damaged easily by 
wave action with a wire strung along the periphery of the beach. The wire had 
short lengths of wire hanging down into the water every few feet and was 
connected to electronics that generated the electrical signals.

Sorry I don't have more specifics.

The report said shark attacks along South African and Austrailian beaches are a 
significant problem, and shark nets aren't entirely effective. Evidently having 
great whites snacking on swimmers is bad for the tourist trade and a lot of the 
smaller beach towns couldn't afford to put up nets.

Rick

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