At 6 a.m., when most right-thinking islanders were deep in lime-kissed dreams of gin and tonics on the beach, Jim Malkin had me riding the bow of a tub-sized boat into gale force spray, looking for fish with sharp teeth to bring aboard.

"These are not what you'd call ideal fishing conditions," said Malkin, a sun-browned fellow who looked dangerously happy on this wave-tossed sea. "That means fewer fishermen to get in our way."

People Magazine recommends a slightly different itinerary for one's first weekend at Martha's Vineyard. After coffee and the morning paper at Walter Cronkite's, stop by William Styron's private beach for mixed drinks and conversation with John Updike, Art Buchwald and Beverly Sills.

Afternoons are for sailing with James Taylor or sunning at the nude beach below Jackie Onassis' modest bungalow. A nap before dinner is essential if you hope to complete the grueling circuit of cocktail parties.

I was prepared for those social rigors. I was not prepared for the born-again fishing fervor of my host, a 35-year-old executive for a New England trucking company who was an avid nonfisherman until a few years ago. Now he keeps tide times posted on his refrigerator door, an 11-foot Boston Whaler parked in his driveway and enough fishing gear to outfit a charter fleet.

At 5 a.m., when he tugged me from sleep, I was singing a duet with Carly Simon.

Martha's Vineyard has been a seagoing sort of place since Leif Erickson visited it in the year 1000. The original islanders, Wampanoag Indians, were fishermen. And in the 18th Century, whalers used it as a port.

But during the last 20 years, this 100-square-mile island that sits seven miles off the coast of Cape Cod has become famous for a different kind of summer sport. Celebrity watching.

"Fishing is not the first thing that comes to most people's minds when you mention Martha's Vineyard," said Jack Koontz, a charter captain, fishing writer and the proprietor of a tackle shop on the island. Fishing boutique is a better description for Derby Jack's, where rods, reels and lures are displayed between framed prints against museum white walls.

Koontz, who grew up in Annapolis and fished the Chesapeake Bay, was seduced by the island during a vacation here in 1970. His clients have included a number of well-known authors, including John Hersey, Nick Lyons and Lillian Hellman, who still fishes with Koontz once a week.

"Her favorite fish are fluke and porgy," said Koontz, 37, who has collaborated on a fishing map of offshore waters that tells you where, when and how to catch white marlin, tuna, striped bass, bluefish, cod and flounder.

To illustrate the local fishing bounty, Koontz tells a story of two friends who were looking for birds on an early morning beach last summer and discovered instead the fin of a big fish in shallow water.

"Both being experienced fishermen, they knew what to do," said Koontz. "They took off their clothes, jumped in the water and grabbed it." The fish was a disoriented, bluefin tuna. According to Koontz and local legend, the men actually beached the beast and took it to a nearby market where it weighed in at 137 pounds. "That may be the world record," said Koontz, "for tuna caught in hand-to-hand combat."

We weren't looking for fish weighing more than 100 pounds when we left the harbor at Menemsha, a lovely place of weathered wood houses that is rarely mentioned without the adjective "quaint." Much of the movie "Jaws" was filmed in this harbor and the rotting wreck of Captain Quint's shark boat still sits on a metal platform near the jetty.

The sound was being whipped into a froth by the wind as we started trolling about half a mile from shore. The spray was regular and only a little colder than my enthusiasm after three hours sleep.

Suddenly sea gulls started dive bombing into the water just a few hundred yards ahead of us. They were feeding on baitfish, small sand eels that look like minnows and only come to the surface when bigger fish chase them there.

One line hit, then the other as we cast into a school of three-pound bluefish. For two hours we fished with the sea gulls. The wind was no less biting than it had been all morning, but we no longer cared. We pulled in more bluefish than we bothered to count, then cut off their heads to save our ankles from their slashing teeth.

As quickly as they appeared, the fish were gone. The sea gulls returned to shore and we motored back to Menemsha. Our fishing chores over, I turned to Malkin and asked him a question I'd been savoring.

"Where is Jackie Onassis' house?"

"Jackie doesn't tell people where I live," said Malkin, with a straight face. "And I don't tell people where she lives."