July 6, 2010
CBF Report: Bay Oysters Are Getting Tougher Naturally, but Reefs Need Greater Protection for Recovery Sanctuaries Can Boost Wild Oysters, Aquaculture Can Boost Economy
(NORFOLK, VA)—A new Chesapeake Bay Foundation (CBF) report released today finds Chesapeake Bay oysters are developing natural resistance to the diseases that have so devastated the Bay's oyster population in recent decades.
To accelerate that natural selection process and the eventual re-population of the Bay with native oysters, the CBF report calls for Virginia and Maryland to create sanctuaries protecting approximately 40 percent of historical oyster grounds, greater funding to rebuild and restore reefs, and stepped-up efforts to prevent oyster poaching from protected reefs. The report also cites growing popularity and profitability of aquaculture, or oyster farming, in the Bay, and urges Virginia and Maryland to encourage aquaculture among watermen through training programs, fee waivers, expedited permit approvals, grants, and other incentives. A surging oyster aquaculture industry could produce millions in new revenue and hundreds of new jobs in the region, the report finds.
"With strong and appropriate management, oysters may well rebound the same as crabs," said CBF President William C. Baker. "Nature seems to be doing its part, and scientists and state policymakers can help by restoring and protecting more historical oyster reefs. Equally important, oyster aquaculture is proving to be a viable and profitable boost to the Bay's oyster industry without depleting the wild oyster population. To paraphrase, we think we can have our oyster and eat it, too."
The report cites scientific research that suggests natural selection is driving increased resistance to diseases and producing hardier oysters, especially in the southern Bay. In Virginia's York River, fewer than 5 percent of oysters are dying from MSX today, while more than half succumbed a decade ago, according to research by the Virginia Institute of Marine Science (VIMS). In the lower James River, 80 percent of oysters were infected with MSX in 1995, but only 24 percent in 2009, the VIMS research found.
Likewise, Dermo, another oyster disease, caused large die-offs of oysters in the 1980s, but today many oysters in both Maryland and Virginia waters seem able to tolerate the disease. In the Lynnhaven and Great Wicomico rivers, for example, the proportion of older, larger oysters with serious Dermo infections has stabilized or decreased, studies show.
This natural disease resistance will accelerate if oysters are allowed to repopulate on sanctuary reefs that are off-limits to harvesting, scientists say. Currently, many large oysters that have developed resistance to disease are being harvested and eaten, preventing their disease-resistant DNA from being passed on to the next generation of oysters. Studies in the Great Wicomico River indicate that about 40 percent of reefs should be protected in order to create a thriving oyster reef community.
This could be accomplished Baywide over time by protecting more existing oyster bottom from harvest and rebuilding and maintaining oyster reefs that once existed decades ago but were destroyed by overharvesting or smothered by siltation. It also will require Virginia, Maryland, and the federal government to increase funding for reef restoration, to more aggressively police poaching of oysters from sanctuary reefs, and to reduce pollution that impairs oyster reproduction.
Oyster sanctuaries also are like powerful water filtration plants on the bottom of the Bay. A single adult oyster can filter 50 gallons of water a day, gobbling up algae and removing dirt and nitrogen pollution. The more reefs that are restored, the quicker the Bay itself can help counter human pollution.
The investments in oyster reef restoration and protection could pay off economically as well, the CBF report found. Over the past 30 years, Virginia and Maryland have suffered $4 billion in lost income with the decline of the wild oyster population in the Bay. The number of oyster shucking houses alone has plummeted since 1974 from 136 to just a half-dozen today, with a proportionate loss in seafood industry jobs. Helping watermen convert to aquaculture could dramatically reverse these trends, bringing in tens of millions of additional income and spurring jobs and income for processors, restaurants, equipment manufacturers, and others.
Virginia is far ahead of Maryland in fostering oyster aquaculture. The state already has established retraining programs for watermen and created an expedited permitting process. The number of farmed oysters in the Commonwealth has jumped tenfold in just three years to nearly 10 million today, with a market value of $2.8 million and total economic impact estimated at about $7 million in 2008. Experts predict that income could increase tenfold in the coming years.
"I believe that aquaculture is the key to the future of the Bay's oyster industry," said CBF Virginia Oyster Restoration and Fisheries Scientist Tommy Leggett. "Scores of Virginia watermen and private companies already are making good money farming oysters. With the right help and incentives, oyster farming could really take off. That would be a win for the seafood industry, the Bay, and the Bay's wild oysters. It's where we need to be heading."
A full copy of the report can be found at cbf.org/oysterreport.