OCEAN DEFENSE sJaws wag as inventors try to find shark repellent
A good repellent would offer a multitude of benefits.
KNIGHT RIDDER NEWSPAPERS
PHILADELPHIA -- The search for shark repellent started more than 50 years ago in the waters of World War II, and still researchers are floundering.
Some say soap will do the trick. Others believe the chemicals found in decaying sharks will keep their livelier biters at bay. A third hopes another fish, the Moses sole, holds the key.
Yet the waters remain murky.
"It's not that we can't find a substance the sharks don't like," said George H. Burgess, director of the Florida Program for Shark Research and the International Shark Attack File. "But can you get enough of that chemical out in the water long enough for it to be a deterrent?"
There are about 75 shark episodes a year around the world and five to eight fatalities, Burgess said.
But researchers say it's about more than preventing injuries; a repellent could help keep lifeguards safe and Navy equipment unscathed, and stop sharks from entering nets meant for tuna and swordfish.
John Williams, a chemistry professor at Temple University, has spent a decade trying to find a way to keep the great whites and the little hammerheads at arm's length.
Right now his repellent -- he's looking for a good name -- looks like white powder, created from a cholesterol derivative and a sugar molecule. It came from the Moses sole fish, a flounder from the Red Sea.
"I 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," Williams said. "I thought, 'We could do something with that.'"
Williams, who also works on developing breast cancer treatments, tried testing the substance, which costs $10,000 a gram, last summer at the Bimini Biological Field Station in the Bahamas.
On a boat surrounded by sharks, he tried to get the sharks to bite on some bait and then shot some of the powder into their mouths to see whether that would scare them off.
"You couldn't really tell if it worked," he said, adding that he plans to return this year.
Eric Stroud, a research chemist in Springfield, N.J., said his "Shark Defense" repellent is far closer to mass-market reach. He was working at a pharmaceutical company when he read that decaying sharks kept others away.
Stroud distilled some of the compounds from dead sharks; the compounds occur only at a certain time in the decaying process, he said. With a $30,000 grant from the National Oceanic and Atmospheric Administration and an "angel" investor, "Shark Defense" now exists.
Several tests in Bimini have proved more than effective, he said.
"We put some chum in the water, and had about a dozen or more sharks all around the boat," said Stroud. With a syringe, they put about 500 milliliters of the compound into the water, and "within two minutes they were gone."
A new sunscreen is possible, he said, but will take longer because of liability issues.
Other companies are now chomping at the bait. Fishery associations want to use the product on their nets, so sharks don't get caught accidentally, Stroud said.
Endorsed by lifeguards
The American Lifeguard Association is endorsing the product. It is working with Stroud to develop an emergency pack that could be shot into the water during an attack, said B.J. Fisher, director of health and safety for the association.
Williams suggested a temporary solution -- liquid soap.
Sharks don't like their mouths being washed out with soap any more than people do, the professor said.