As he's being lowered into the water off southern Australia in a shark cage, author Peter Benchley has a sudden morbid thought.

"One of these days one of these fellows is going to take revenge for `Jaws,' " said the novelist whose shark tale cleared beaches 25 years ago, "and I don't want to be around."

He's safe. Great white sharks don't appear to hold grudges. And if the sharks of the world could somehow understand what Benchley is doing now to protect them and educate the world about their behavior, they'd probably watch his back, not bite it.

A quarter-century after "Jaws" chilled all who read it, Benchley caught up with sharks for a "National Geographic" special that airs Sunday on CNBC. His impressions and David Doubilet's photos are also in April's issue of the magazine.

If there's one thing that his research in Australia and off the coast of South Africa taught him, it's that he could not write "Jaws" today.

"I could not posit the situation now that I posited then -- sort of a rogue shark that came around and wouldn't go away because it had found a steady diet of human beings," Benchley said in an interview over a seafood lunch (crab, not shark).

Scientists have learned that much of the shark behavior they used to ascribe to aggression is simply curiosity.

"I attributed to them a kind of marauding monsterism that became what `Jaws' was," he said. "Now we know that sharks do not attack boats. The way they decide what to eat is by biting it."

During the split second after a shark sinks its teeth into human flesh, it makes a complex calculation to determine whether the prey is worth the caloric energy needed to kill and eat it, Benchley said.

Sharks consider humans, for the most part, too bony and lean to make a good meal. Fatty seals are much better. That's why 75 percent of humans attacked by great whites are spit out.

One bite is often enough, as Rodney Fox learned. He was attacked in 1963 while spearfishing off the coast of Australia, and needed 462 stitches. Rather than begrudge the species, he's spent much of his time working to protect sharks, and accompanied Benchley on his research mission.

Growing up, Benchley had always been fascinated by sharks during summers in Nantucket, and wanted to write a book about them. Clearly, others shared his interest.

He doesn't regret "Jaws," or the more than 20 million copies of the book that were sold. It gave a struggling free-lance writer a successful and comfortable career.

"Completely inadvertently, it tapped into a very, very deep fear," he said. "If I had done it on purpose, it would be one thing. But I didn't know for years what was responsible for the enormous phenomenon of `Jaws.' "

He didn't like the "momentary spasm of macho nonsense" that made people go out and kill sharks in the wake of his book. He's comforted by the letters he gets to this day from people who say his book triggered an interest in sharks and a desire to preserve them.

The development of modern fishing technology, like long lines that stretch as far as 80 miles, has done more harm to sharks than any response to "Jaws," Benchley believes.

He smiles when reminded of the nightmares "Jaws" caused, and how John Williams' ominous score for the movie became a symbol of impending doom.

"I felt that way about `Psycho.' When I went to see `Psycho' in 1961, my date wet her pants," he said. "I cannot be responsible for how people react. I can only be responsible for what I do."

Published 4/8/2000