Six hundred feet long, the hulk was home for a million fish. She made a reef with enough nooks and crannies to shelter anything up to a baby whale in size. If ever he got the guts or the time, he would like to explore it, though it had been stripped clean of souvenirs years ago.

"What are you doing down there?" Jake's voice came from a tinny acoustic speaker on the sub's dash. "Did you go on strike?"

Mike spoke clearly and carefully, for the water distorted voices through underwater acoustic mikes. "Not yet. But your stupid so-called submarine scared all our conch away."

"You're at that wreck! I can tell from the echo. Stop farting around and get some tagged."

Mike was getting tired of arguing with Jake, but he had to put up with it. A tight budget was a tight budget, and a Ph.D. candidate was only slave labor till graduation day.

He maneuvered the sub toward a sandy spot near the Leta's hull. He turned off the battery. The Whine Bottle thumped to the bottom, sixty feet below the surface. He peered from the cockpit for conch. None.

Jake seemed to think the bottom was carpeted with them but claimed he had an ear problem and hardly ever dived.

Mike took his Nikon camera and strobe light, placed his hands on the top of his Plexiglas windshield, pushed, and floated up and out. He finally found a colony of pink conch and began to stalk them silently. If you didn't spook them, it was quite easy. He tagged them with markers for size and sex and shot their pictures using the strobe.

Conch divers who took them would mail the tags in later, it was hoped. If the project could pinpoint spawning grounds and migration trends, correlated with temperature changes, they might save the great pink conch.

But results this year were spotty: No one bothered to mail in tags. No one in the Bahamas except Jake, Mike, and the Minister of Fisheries himself seemed to think the project was worth a damn.

And when the natives cleaned out the last conch, then it would be too late.

"Are you tagging them yet?" The voice was garbled.

"I'm separating the ladies from the gentlemen. Get off my back."

"Use a BPST on the biggest one you see."

The battery-powered sonic transmitter was Jake's baby: he had developed it and was very proud of it. It was the size of a small salami. You could pick up its signal through a transducer on the barge, or on Neptune's Folly, at almost a quarter of a mile. The BPSTs cost a hundred dollars to make, and you did not expend them lightly.