There aren't many oysters on the floor of Maryland's Choptank River-but there are millions floating near the surface in floats owned by an oyster hatchery getting statewide attention for its success in raising oysters where they'd nearly been wiped out.

The Marinetics company has about 5 million oysters living on 3,000 floats in a river near Cambridge. The business, founded by a husband and wife team interested in oyster recovery, raises disease-free oysters-a rarity in the troubled Chesapeake Bay watershed.

"It's not a real easy way to make a living," said Kevin McClarren, who manages the oyster hatchery, also called the Choptank Oyster Co. The oysters McClarren raises, marketed as "Choptank Sweets," end up on restaurant plates, bought by chefs who need a steady supply of healthy oysters.

Three of Maryland's commercial oyster growers use floats to raise the oysters, The (Baltimore) Sun reported. That's because the bottom of the Bay and its rivers are choked with sediment, making oyster life difficult.

"It's not fail-safe, but the risks are probably quite a bit less than if they were grown on the bottom,'' said Karl Roscher, aquaculture coordinator for the Maryland Department of Agriculture. Roscher told the newspaper that on the bottom, oysters grow about an inch a year, a slow rate of growth that makes them susceptible to disease before they reach the market size of 3 inches.

The floating oyster hatchery in Castle Haven has sold 365,000 oysters in the last two years. McClarren said the hatchery is breaking even and could turn a profit within two or three years. The company aims to sell a million Choptank Sweets a year.

At a hatchery on the Western Shore, Pasadena resident Andrew Murdza also raises oysters near the water's surface. He uses a device he calls an "oyster hotel," a wire cage filled with barley straw and more than 500 spat, or baby oysters.

Murdza is raising his oysters with a goal of releasing them into the Chesapeake for restoration efforts, not to sell. He said he tried the surface oyster method with 87,000 oysters at 175 different locations in the Chesapeake and the Magothy River. All but three survived after six months.

"It was the most beautiful thing,"' he told The (Annapolis) Capital recently. He plans to open an oyster hatchery later this year.

Richard Pelz, a founder of the Chesapeake Oysters Guild, said he has been using floating oyster reefs for almost 20 years.

"It goes totally against tradition. Oysters are normally found on the bottom," Pelz told The Capital. "I had one guy tell me that if God intended oysters to be on the top, he would have put them on the top."

The state is trying to encourage such activities. A 2005 Maryland law set up a new process to get permits for aquaculture, and Roscher said that a new state aquaculture council will push for a new loan fund to help with aquaculture startup costs. The interim report of the 21-member Maryland Oyster Advisory Report also envisions a shift to oyster aquaculture from wild harvest.

Billy Martin, a Jessup seafood distributor who sells Choptank Sweets, said he has seen the potential environmental benefits of raising oysters firsthand. He toured the Marinetics' site and counted eight dolphins in a small stretch of the river near the oysters.

"I thought, 'Dolphins in the Choptank River,'" Martin said. "I've been here all my life. I've never seen that."