BALTIMORE (AP) -- Maryland's oyster population is continuing to rebound, with more oysters surviving diseases that have plagued the shellfish in the past and hindered Chesapeake Bay restoration efforts, state officials said Wednesday.
Fall oyster survey results released by Department of Natural Resources showed population and reproduction increases for a second straight year. The survey also found that Dermo and MSX, the two diseases that have decimated Maryland oysters, remained far below long-term averages.
"While the population remains at less than 1 percent of historic levels, it's encouraging to hear that these natural filters are on the incline," DNR Secretary John Griffin said, adding that oysters are vital to improving water quality and supporting a healthy ecosystem.
Griffin credited the increase in part to survival among the large number of oysters hatched in 2010. The survey found a 93 percent overall survival rate in samples taken by surveyors.
DNR Fisheries Service Director Tom O'Connell said oysters may be developing a resistance to the diseases, helped by the establishment of sanctuaries that provide adults oysters "with a safe place where they can handle the stresses of disease and the ups and downs of reproduction."
Watermen had another theory.
"A lot of it's got to do with that we are power dredging in the bay, which cultivates the bottom and brings the shell out and cleans it up," said Robert T. Brown Sr., president of the Maryland Watermen's Association.
That provides a place for young oysters, known as spat, to set on the shells of adult oysters, and allows adult oysters to feed better, Brown said.
Whatever the reason, "it's about time to have some good news," Brown said.
Mike Naylor, DNR shellfish program manager, said there is no evidence that power dredging increases the long-term harvest of oysters, but the department is in the third year of a five-year study of the issue. The department will make adjustments based on the results of the power dredging study and other research, Naylor said.
The survey found the population at its highest level since 1999. MSX, meanwhile, was at a record low and Dermo increased moderately from a record low in 2011, the survey found.
Waterman Scott Todd, who works out of Hoopersville on the lower Eastern Shore, said the numbers were not a surprise to him. Todd said he had just finished filling out his harvest report for March, and he caught his limit nearly every day. He said other watermen he knew were having the same luck.
"It's been a long, long time since we've done that," Todd said.
Todd also said more power dredging should be allowed, as well as allowing watermen to spread oyster shells on the bay bottom. Todd said state officials have prohibited the spreading to prevent disease, but the idea should be revisited, adding that a Virginia processor has offered to sell 80,000 bushels of empty oyster shells for the effort.
"That was probably a smart move on their part at that point," Todd said. "But the diseases aren't showing up as much anymore."