SOLOMONS, Md. - As watermen have done for decades, Ronny Jetmore guides his small boat into a creek off the Patuxent River to tong oysters from the bottom.

Oysters, once so bountiful in the Chesapeake Bay that their shells were used to pave roads, have become scarce in recent years, decimated by disease and pollution.

But Jetmore knows where to find these oysters because he helped put them there.

In a departure from the hunter-gatherer tradition of Maryland's watermen, Jetmore and others in Calvert County have banded together to try raising for themselves what nature is no longer providing in abundance.

"This is encouraging," says Jetmore, as his tongs pull up clumps of oysters from a patch of creek bottom that the watermen have leased from the state.

Put overboard in 2007 as "spat," or baby oysters, some are nearly big enough to sell to a restaurant or shucking house.

Experts hope this fledgling experiment in Calvert County, now in its second year, will encourage more watermen to switch from fishing to farming the bay. Aquaculture, they say, is the only viable path to reviving Maryland's faded oyster industry, which once supplied the nation.

"We . . . could produce a lot more oysters using the bay bottom as farmland," says Kennedy Paynter, an oyster researcher at the University of Maryland.

Work in aquaculture also might offer the best hope for keeping some vestige of the Chesapeake's iconic watermen, who have dwindled in number along with the crabs, oysters and fish that used to fill their boats year-round.

"I don't have a lot of oystermen left," says Tommy Zinn, president of Calvert County Watermen's Association.

Watermen who in decades past would switch from crabbing to oystering in the fall are now getting other jobs in the winter because there aren't enough bivalves left to harvest to make a living.

The bay's once-thriving oyster industry has been devastated during the last two decades by a pair of parasitic diseases, MSX and Dermo. The harvest fell from more than 2.5 million bushels in 1981 to less than 83,000 bushels in 2007.

The diseases are not harmful to humans who eat infected oysters, but they kill the shellfish before they grow large enough to harvest. The die-off has added to the bay's woes, scientists say, because oysters are prolific filter feeders, cleaning the water as they consume vast quantities of algae and remove sediment and other pollutants.

The situation is so bleak that federal and state officials are weighing whether to introduce disease-resistant Asian oysters in an effort to restore the bay's oyster population, for both its ecological and commercial value.

While the diseases continue to limit the bay's oyster population, experts say they have figured out ways to cultivate the native bivalves in oyster farms so they can evade the diseases and rebuild the industry.

Some entrepreneurs are growing oysters on floating racks rather than on the bottom. Others are trying chemically sterilized oysters. In both cases, the oysters essentially outgrow the diseases, reaching market size before they die. Raising oysters farther up creeks and rivers also seems to help, since the diseases are more virulent in the salty water nearer the ocean.

"The disease is not less of a threat, but they're figuring out ways to get around it," says Doug Lipton, a University of Maryland economist who specializes in the seafood industry.

Given the modest successes to date, experts are encouraging watermen to try the new techniques, all of which involve cultivating oysters rather than foraging for wild ones. It's been a tough sell. Maryland watermen traditionally have resisted aquaculture, fearing that they would be forced off the water by large corporations.