With rapidly growing interest in rearing foreign oysters in the Bay, the National Academy of Sciences, in an unusual move, is considering a review of the risks and benefits of using the Southeast Asian bivalve in the Chesapeake.

The study which would be overseen by the Academy’s Ocean Studies Board could begin this spring and conclude about a year later, with a final report not only about risks and benefits, but also a summary of research needed to make informed decisions about the future of the foreign oyster, Crassostrea ariakensis, in the Bay.

Normally, the academy — a nonprofit created by Congress to advise the federal government on science policy — focuses on broader national issues, but the Ocean Studies Board agreed that the oyster review was justified after an early February meeting with scientists and officials from the Bay region.

“We believe this has broader implications for aquaculture and the whole invasive species debate across the country,” said Morgan Gopnik, director of the NAS’ ocean board. “We normally wouldn’t do something that is just a very local issue, but I think the conclusion was that this really has broad implications for national policy about how we deal with aquaculture and how we deal with introduced species.”

The study, which is expected to take about a year, could begin by late spring — or as soon as officials put together the roughly $300,000 the report will cost. By mid-February, they had gathered about two-thirds of the money, with the bulk of it coming from the EPA, the National Oceanic and Atmospheric Administration, the Maryland Department of Natural Resources, and a smaller amount from the Chesapeake Bay Foundation.

Recent studies have found that ariakensis, also known as the Suminoe oyster, grows much faster than the native species, Crassostrea virginica, and appears resistent to the diseases that have devastated the native oyster population.

That’s created a huge interest among watermen in both states and by the seafood industry about the oyster’s potential. The Virginia Seafood Council is working on a proposal to ratchet up the use of sterile ariakensis oysters in aquaculture from the 60,000 grown experimentally last year.

Others are concerned that efforts to render the foreign oysters sterile may not be totally effective, and could eventually result in a reproducing ariakensis population in the Bay. Because ariakensis is poorly studied, some fear a wild population could have unpredictable consequences for the Bay, although many contend it could also have beneficial, water-filtering impacts.

The uncertainties have resulted in a long list of research questions being proposed, which some proponents of the oyster fear could serve to delay its use. As a result, a sentiment emerged late last year for an outside body to review the issue.

“We pretty much have a consensus that the NAS study is a good thing to do,” said Bill Goldsborough, senior scientist with the Chesapeake Bay Foundation, which originally proposed the academy review. “It is important they have the support and buy-in from all the different players.”

The NAS study would examine the ecological and socioeconomic risks and benefits of three alternatives: using sterile oysters in aquaculture, placing a reproducing population in the Bay or barring the use of ariakensis altogether. The study would address how ariakensis might affect the Bay’s ecology, including effects on native species, water quality, habitat and the spread of human and oyster diseases.

In addition, the scientists would examine the impact ariakensis may have on the recovery of native oysters, and the extent of its potential range in the Bay and along the East Coast. They would also investigate the adequacy of existing regulatory frameworks to monitor oyster use.

“The committee would try to give its best scientific opinion about the potential ecological effect of introducing this oyster and then, where it felt there just wasn’t enough knowledge to even answer the questions, it will point out what additional research is needed,” Gopnik said.

Ultimately, though, she said research will not answer all of the questions, and policy makers will have to make a call on the oyster. “You can’t always wait until you have perfect science because things happen; the world moves on,” Gopnik said. “You have to make decisions.”

Different scientists around the Bay region have suggested that, once a set of research priorities were agreed upon, many of the key concerns could be addressed with three to five years of work. So far, the only research on the oyster has been conducted by the Virginia Institute of Marine Science, which is required by the state General Assembly to explore the potential of nonnative species.

Meanwhile, at least one federal agency, the National Oceanic and Atmospheric Administration, plans to join the research effort. Lowell Bahner, director of NOAA’s Chesapeake Bay Office, said he hoped to free about $50,000 in his office’s budget to begin preliminary research on ariakensis as soon as this summer.

Although the NAS study will offer a broader research agenda, Bahner said it was clear that certain basic questions will need more attention, such as whether sterilized oysters will become capable of reproducing over time, whether the foreign oysters would hybridize with the native species, and whether the oysters would spread along the East Coast.

“I think it’s an important enough issue that we should try to reprogram some money toward answering these questions if we can,” Bahner said. “We won’t answer all of those, but at least we can get it started.”
In another development, the Maryland DNR, reversing its earlier stance, has decided that it would allow scientists to perform experiments with ariakensis in Maryland’s portion of the Bay.

In the past, the department had opposed in-water testing, either in Maryland or Virginia portions of the Bay. But the department is willing to participate in a research program laid out by the NAS, said Eric Schwaab, the DNR’s fisheries director.

“We still believe there is a lot that can be learned without in-water testing, but the door is not closed to in-water testing if it can be done reasonably safely and it is determined to be necessary,” he said.

Schwaab stressed that the department remained committed to efforts to restore the native oyster.
The department’s modified position coincides with a position statement issued by the University of Maryland Center for Environmental Science, which said some “carefully controlled” studies were needed to assess the oyster’s performance and ecological consequences “in the extensive low-salinity, turbid environments prevalent in Maryland.”

The position statement supported continued small-scale aquaculture experiments with ariakensis in Virginia with strict safeguards to prevent an accidental introduction, but opposed any placement of reproductively capable oysters, or aquaculture tests that pose significant risks of introduction, as “irresponsible.”

More research, the statement said, may show that using sterile oysters would pose little risk of an accidental introduction in the Bay, or even that the oyster could be beneficial to the Chesapeake. But it said a research agenda must first be carried out in a “timely manner without compromising the rigor of science or rushing to judgment.” In the meantime, it said “there is no reason to conclude” that efforts to restore the native oyster should be halted.

Late last year, both VIMS and the CBF issued similar position statements, calling for continued aquaculture tests with ariakensis, but opposing stepped-up aquaculture efforts or the use of reproducing oysters until more study is completed.