Out Of Shark Repellent? Use Soap!
It looks like they might be close to finding a shark repellent that actually works. The problem is finding a way to keep enough of the substance in the water long enough to deter the sharks. So far, chemicals found in decaying sharks seem to do the trick. This one's currently called "Shark Defense" and a sunscreen version is even in the works.
Professor Williams (above) is working on another one that uses a substance from the Moses sole fish, a flounder from the Red Sea. He got the idea from a National Geographic picture that showed a shark trying to bite a fish, and the fish excreted some kind of liquid and it kind of froze the shark in place - it couldn't close its mouth.
He also says, in a pinch... use liquid soap. I'm packing some Dawn next time I go to the beach.