ANNAPOLIS – U.S. Rep. Wayne Gilchrest called for federal oversight over introducing non-native oysters in the Chesapeake Bay, an area where the jurisdiction is currently “fuzzy,” he said after a congressional hearing here Tuesday.
Gilchrest, R-Kennedyville, said he hopes to forge collaboration between the states and federal agencies, and has introduced a bill this year that outlines federal protection against “invasive species.”
To foster those relationships, he invited states’ scientists and representatives from federal agencies, industry and environmental groups to Tuesday’s hearing.
The introduction of Asian oysters to supplement the moribund native variety has sparked controversy for more than 10 years. Bay states have tried various methods, without success, to revive the declining native oyster population. It’s that failure that has led both Maryland and Virginia to pursue introduction of other oyster species.
Parties differ on who’s responsible for non-native oyster introduction. The federal Environmental Protection Agency would have control over any shellfish introduction that involved Clean Water Act regulations, such as attempts to create a structure on which the oysters could live.
Meanwhile, the two states disagree on how readily the Asian oyster species selected, the large and disease-resistant Suminoe, could be introduced to the bay.
Maryland’s Department of Natural Resources favors adding reproductive non-natives pending an environmental impact statement, while Virginia has begun controlled experiments using genetically sterilized ones.
Many scientists fear that introducing reproductive oysters into the bay would wreak havoc if the Asian oyster flourishes, becomes “invasive” and displaces native bay species.
Oysters are the stuff of legend in the Chesapeake, an estuary named after the Algonquian Indian word for “great shellfish bay.” Oyster habitat once covered 450,000 acres of the bay, and Maryland harvested as many as 15 million bushels per year during the 19th century.
But over-harvesting, pollution and parasitic diseases led to an oyster crash in the 20th century and now native oysters are nearing extinction. Last season’s oyster harvest amounted to only 53,000 bushels, the lowest catch since Maryland began keeping records in the 1870s.
The watermen who harvest the diminishing stock of oysters have met economic devastation. Within a generation, a fleet of 5,000 oystermen has shrunk to fewer than 200 today, said Larry Simns, president of the Maryland Watermen’s Association, which supports the introduction of disease resistant non-native oysters.
Laboratory tests of the Asian oysters conducted by the Virginia Institute of Marine Sciences have shown them to be resistant to the two parasitic diseases – MSX and dermo – that ravaged native oysters.
“We’re basically trying to find an oyster that will work,” said Standish Allen, a geneticist at the Virginia institute who is overseeing the sterilized oyster experiment.
The National Research Council published a finding on non-native oysters that validated Virginia’s strategy of studying sterilized oysters in a controlled environment and urged caution against the introduction of reproducing oysters favored by Maryland.
“If the Suminoe oyster becomes reproductive and viable it’s only a matter of time before it spreads to other estuaries throughout the East Coast,” said Robert Whitlatch, a member of the National Research Council’s committee.
Other invasive species, such as the gypsy moth and the zebra mussel, have caused large-scale economic damage.
Gilchrest’s bill concerning invasive species states that the Great Lakes region has spent about $3 billion in the past 10 years to combat zebra mussels that clog power plants and water facilities.
But Simns, the watermen president, downplayed the notion of an out-of-control oyster population in the Chesapeake.
“There’s one predator they’d have a hard time keeping up with, and that’s the Maryland waterman,” he said. “We’ll take care of the overabundance.”