It was the end of a long, hot day for the fishing guide at Flamingo, a camp on the Florida Bay that also sports some first-class birdwatching.

The guide's last daily function is to clean the catch, and he was fileting away with a sharp knife when an elderly female birdwatcher stopped by.

"Oh," she said, "how can you do that? You're wasting so much."

The guide didn't say a word. He just picked up the carcass of the finished fish by the tail and presented it to the woman. She turned up her nose and stomped off.

People are always bellyaching about fileting, which is the only efficient way to clean fish if you've got enough to make it worthwhile to take them home. Onlookers find it offensive because after the work is done there is still a huge chuck of fish matter left. What they don't discern is that leftovers are the same as what would be left over on the dinner plate if the fish were cleaned the conventional way.

The only difference is that this way the leftovers don't get cooked.

Good fileters can be found at most fishing centers, like the Rod 'n' Reel at Chesapeake Beach. But the very best men with the knife are usually private people who take their fishing seriously and who have learned over the years that half the satisfaction of the sport comes from putting their personal stamp on every aspect of it, including cleaning the catch.

Up on Block Island, Gordon Goold puts on a show every night. He's given to evening flounder fishing. It's a long haul home in the dark and he doesn't like to leave the fish overnight. He has a bright electric bulb outside his cottage and a scarred wooden board under the porch.

There is a ritualistic style to Goold's work. He spends five minutes at the whetstone, carefully honing the knife to a razor edge, testing it against his thumbnail until it scrapes off tiny flecks. His first cut is directly down along the center of the fish, then he cuts along the backbone and peels the meat from the bones with gentle flicks of the blade. The rib cage filet is taken the same way, only it's smaller than the backbone half.

He works in silence in the brisk night breezes under the glitter of stars, with the sweet smell of the Great Salt Pond washing over the operation. Goold doesn't talk, but people gather anyway, just to see a job done right.

There's a good man on the Chesapeake, too. John Page Williams runs the Chesapeake Bay Foundation's field trips and helps cut food bills by including fishing in the field operations for CBF students. They catch croaker and sea trout, bluefish and flounder near the CBF outpost at Great Fox Island, and the students get as much kick out of watching Williams at work with the knife as they get from their research.

Williams' keys to fileting: The proper knife and the proper cutting surface. His knife is the Rapala, made in Finland, with an edge that never seems to dull. His surface is a battered fish cleaning station on the dock, but any wooden tabletop will do if it's the right height and can stand scarring.

The four steps of fileting:

1. Place the fish on its side and make a diagonal cut from the back of the fish's head to the bottom of the belly cavity.

2. Cut along the edge of the backbone from the top of the diagonal cut back to the tail.

3. Spread the backbone cut with you free hand and make tiny cuts into the exposed flesh, following the line of the vertical bones and peeling meat from bone as you go. Halfway down is the backbone, at which point you'll have to start cutting less deeply to allow allowances for the rib cage at the forward end of the fish. The ribs do not extend to the rear half of the fish.

4. When you reach the tail, cut the whole filet away from the fish and lay it on the table, skin side down.Make a diagonal cut into the flesh at the tail, hold onto the tail end and peel the meat away from the skin. It should come off easily, like removing a pat of butter from its little paper tray.

This technique works on any fish bigger than hand-size and smaller than about 30 pounds, which covers most fish the average angler will boat. Williams says it's the only way he'll handle fish. "Look, we're feeding people that normally don't fool with seafood. This cuts out bones, it cuts out out skin, it cuts out the mess."