SAN JUAN, Puerto Rico -- Excited by the scent of blood, a dozen sharks dart about in a frenzy as a researcher dips a pole in the sea and squirts out a clear, yellowish substance. Within seconds, the sharks jerk their snouts away and vanish.
Researchers test a shark repellent on a lemon shark at the Bimini Biological Field Station in South Bimini, Bahamas.
Researchers say they finally have found a potent repellent to drive away sharks, after testing off Bimini island in the Bahamas. It's a goal that's eluded scientists for decades.
If proven effective, the repellent one day might protect divers, surfers and swimmers. But researchers say that would require much more study. First they hope it can protect sharks -- in decline worldwide due to overfishing -- by reducing the numbers caught needlessly by long-line commercial fishermen.
"You introduce this chemical, and they all leave," said lead researcher Eric Stroud, a 30-year-old chemical engineer from Oak Ridge, N.J. "It works very, very well."
