Planting in Choptank River seeks to revive Md. harvest YOUNG OYSTERS PUT TO BED


The name of John Dillow, a marine biologist with the Living Classrooms Foundation, was spelled incorrectly in an article yesterday about the planting of oysters in the Choptank River.

The Sun regrets the error.

HORN POINT -- Growing oysters puts nicks on your hands, mud on your shirt and strain on your back.

Lift a 30-pound bag of shells out of the tank. Toss it down the line. Load it into the truck, then onto the boat, then into the water. Lift. Heave. Toss. Catch. Nine hundred bags -- about 13 1/2 tons -- make a morning's work.

"That mud, you wear it well, man," John Zillow teased a Living Classrooms Foundation student loading bags of oyster shells onto a truck yesterday morning at the point, just west of Cambridge. "This evening, we'll have a big hydrogen peroxide party."

Mr. Zillow, 13 students and a group of watermen and scientists spent most of the day on the Choptank River, putting very young oysters into nursery beds upriver near Secretary.

The planting of 1.5 million oysters -- 900 bags of shells harboring the dot-sized "spat," as young oysters are called -- was the first major project by the Maryland Oyster Recovery Partnership, a group of watermen, scientists, state biologists and others dedicated to reviv-ing oysters in the Chesapeake Bay and its tributaries.

"We want to see how well this works," said Pete Jensen, a partnership member and director of fisheries for the state's Department of Natural Resources.

"We want to see how well they survive."

The project, supervised by University of Maryland scientists Don Meritt and Ken Paynter, is one part of a program designed to increase the numbers of oysters in the bay.

Once a thriving industry on the Eastern Shore -- the 1986 harvest was 1.5 million bushels, with a dockside value of $16.6 million -- the oyster population in the bay and its tributaries has been ravaged by two parasites, commonly known as Dermo and MSX.

Both swept through the bay's oyster population in the mid-1980s, with disastrous effects on the harvest. In 1987, the harvest fell to 976,025 bushels.

Since then, the harvest has continued to decline, never topping 500,000 bushels. Last year was the worst of all: 79,617 bushels with a dockside value of $1.3 million.

People not affected

The parasites don't affect people at all, scientists said -- but they kill oysters effectively.

"It's not a health threat," said Dr. Roger Newell, one of the University of Maryland scientists on hand for yesterday's planting. "All the watermen find is empty shells."

The parasites are under study, and their origin isn't clear. But scientists have linked the mortality rate in oysters to salinity levels in the bay and tributaries: Lower salinity levels send the parasites into abeyance, and fewer oysters die.

"Those diseases are going to be within oyster stocks forever," said Dr. Newell. "There's no way to eradicate them. We're TC recognizing that we have to manage round the problem."

To that end, young oysters are being spawned in hatcheries, then put out in the Choptank River.

In about two months, the oysters planted yesterday will be released from the mesh bags and moved into the middle of the river. Testing of the waters and of the oysters themselves will continue through the three to five years required to produce a mature, ready-to-eat oyster.

No harvesting allowed

For now, the test areas will not be harvested.

"We've never before had an opportunity where we could actually count the hatchery-produced oysters," said Dr. Newell.

But the partnership persuaded watermen that it would be in everyone's interest not to harvest in the designated areas so scientists will be able to monitor survival rates in the hatchery-spawned oysters.

Ten percent to 20 percent survival would be optimal, said DNR's Mr. Jensen. More likely is 1 percent or 2 percent.

Over time, the partnership hopes to develop an economically feasible plan to plant oysters in the Chester, Magothy, Nanticoke, Patuxent and Severn rivers. The expanded effort could not only boost the moribund oyster industry on the Shore, but also contribute to the long-term health of the bay and its rivers.

"If we had more oysters, they would actually improve water quality," said Dr. Newell.

"They filter the water. . . . They also form these reef communities and support fishing. Fishermen fish over those reefs."

The project has several hurdles to clear. First is determining the oyster survival rate. Then comes the economic question: Can this kind of seeding be profitable?

Oysters can be grown relatively cheaply in a hatchery -- scientists put males and females in a tank and raise the water temperature to induce spawning.

Planting is labor-intensive

But planting oysters is labor-intensive work.

The project is using student labor donated by the Living %J Classrooms Foundation, boats and expertise donated by watermen and research and science from the University of Maryland and the Center for Environmental and Estuarine Studies, as well as the state's environmental agencies.

It takes a lot of hands to gather the shells -- recycled from shucking houses on the Shore -- bag them, put them in tanks when the larvae are ready to attach, then take them out, transport them and put them in the nursery areas to grow.

"It's not rocket science; it's just menial labor," said Robert M. Pfeiffer, executive director of the Oyster Recovery Partnership, as he watched the students work near Jamaica Point, the nursery site.

"One of the questions we have to answer is, how do you reduce the costs?"

"The logistics become a real killer," agreed Dr. Newell.

But that problem lies some distance down the road. For now, scientists hope that the little oysters put in low-salinity areas in the Choptank River will grow and prosper, helping researchers and watermen alike.

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