Dermo

Eastern Shore watermen got more bad news about water quality yesterday, as high bacteria levels forced state officials to expand an area of Pocomoke Sound that is off limits to the harvesting of oysters and clams.The restriction, effective Sept. 1, closely follows the state's unrelated six-day closure of the lower Pocomoke River this month, when thousands of fish were killed, in part, because of a microorganism called Pfiesteria piscicida in the water.In yesterday's action, the Department of the Environment ordered a halt to shellfish harvesting in the Pocomoke Sound after routine water sampling showed unsafe levels of fecal coliform -- contamination that state officials blamed on wildlife and other natural sources.

Dermo, one of two diseases that ravaged the Chesapeake Bay oyster population in the early 1990s, showed up in oyster bars throughout the bay during surveys last fall, according to state officials. But the oysters on those bars were surviving at greater rates than they did in 1992 and 1993, the years of the record-low harvests, suggesting they might be more resistant to the disease. "We can't say scientifically that that's the case," said John Surrick, spokesman for the state Department of Natural Resources.

Maryland's oysters, though ravaged by disease and loss of habitat, are showing some signs of resilience, state biologists reported yesterday. A survey last fall of Maryland's part of the Chesapeake Bay indicates that while most oysters are infected, fewer are dying from the parasitic diseases that have devastated them over the past 25 years, according to the Department of Natural Resources. "They're not out of the woods," said Chris Dungan, who tested the oysters for diseases at a joint state-federal laboratory in Oxford.

The Environmental Report Tuesday, 9:55 a.m. WEAA (88.9 public radio). Host Morning Sunday provides reports on air quality and tips to help regreen cities. Outdoors Maryland Tuesday, 7:30 p.m. (Repeats Thursday, 5:30 a.m., and April 16, 5:30 p.m.) MPT "Chino Farms." The largest land set-aside deal in Maryland's history has created a living laboratory in Kent County on the Eastern Shore. The 5,200-acre Chino Farms is now home to a number of natural resource experiments, which include restoring an ancient prairie and the sparrows that once lived there.

OYSTER harvest totals may drop from the previous year when the Maryland season ends in April, but biologists still see some positive signs. Surveys show that more Chesapeake oysters are surviving amid the presence of two longtime deadly diseases, Dermo and MSX, indicating a growing resistance. The oyster-killing pathogens are still found throughout much of the bay and scientists had expected a high mortality rate following two dry years that raised salinity levels in the estuary. The improved survival rate of the oyster -- an important pollution fighter in filtering the bay's brackish water -- gives renewed hope for Maryland's ambitious restoration program.

Maryland watermen have experienced five years in a row of meager oyster harvests. And this season, which ended late last month, proved no exception. The yield remains in the vicinity of 400,000 bushels. Twenty years ago, the harvests each year ran in excess of 3 million bushels.Parasitic disease has taken a dreadful toll on the oyster. Two persistent infections, MSX and Dermo, have made their way up the bay in recent years, greatly affecting Chesapeake oysters. These bivalves also seem to be adversely affected by the bay's declining health caused by pollution and overfishing.

Virginia fisheries regulators have approved unanimously a plan to test Asian oysters in the open waters of the Chesapeake Bay as part of an effort to restore the state's shellfish industry decimated by the diseases Dermo and MSX. The Virginia Marine Resources Commission voted Tuesday after hearing objections from Maryland and Delaware scientists who said they feared the introduction of non-native species in the bay. A number of non-native species have...

HORN POINT -- Biologist Donald Meritt gently heats the water in a black tank until female Chesapeake oysters start cracking open their shells and squirting geysers of cloudy fluid teeming with millions of eggs. Within moments, streams of gray liquid starts trickling out of the males in the same tank. "Didn't know you were going to an oyster orgy today, did you?" Meritt asks guests to his breeding laboratory at the University of Maryland Center for Environmental Science, Horn Point, on the Eastern Shore.

It was just after noon when Eric Cantler docked the Diana at the Maryland Watermen's Cooperative in Annapolis. On the bottom of his workboat glistened a dark, wet heap of oysters -- early returns on the first day of Maryland's 1991-92 oyster season.Cantler, who has been oystering since he got out of school 20-some years ago, said yesterday that there seem to be a few more oysters on the Chesapeake Bay bottom this fall than there were last year."It's better," he said, as he and his son-in-law, Robert Sullivan, prepared to shovel their day's harvest into a bushel-sized metal bucket for transfer to wheelbarrows on the dock.

OCEAN CITY -- Even if the number of crabs in the Chesapeake Bay is no lower than historic long-term averages -- as a new report suggests -- Maryland is in no rush to ease restrictions on crab fishermen, the state's chief fisheries official said here yesterday.The state might not be in the position of having "to avert a crisis, but we're going to maintain stability," said Pete Jensen, director of fisheries for the Department of Natural Resources. "We're not going to wait for a crisis to jump up and bite us."