The sanctuaries are located in upstream portions of rivers where scientists hope salinities are high enough to allow the oysters to survive but low enough to control the diseases. This year's project, seeded with young oysters raised in a hatchery at the University of Maryland's Horn Point Environmental Laboratory, consisted of 5 acres. Peiffer said that as many as 20 additional acres may be seeded next year, including possible projects on the Severn, Patuxent and Wicomico rivers. If there is a way to get dependable good recruitment, which we don't have a way to do yet in Maryland, we could probably mitigate a lot of effects of these diseases. And that is the key.
Oysters often live long enough to reproduce, but many die before reaching market size.
In Maryland, the harvest has fallen from 3.2 million bushels in 1973 to 124,000 in 1993. With the setback of disease, the harvest rose to 164,000 bushels last year. Though lethal to oysters, the diseases do not pose a threat to humans. The situation in Virginia, meanwhile, remained bleak. Salinities in 1993 and 1994 remained high enough in most areas for the diseases to continue to thrive.