Corps team works to bring back 'Chesapeake Gold'  

Workers seed the Great Wicomico reefs. Seeding involves dumping baskets of oysters overboard, using GPS to determine the exact location of the constructed underwater reefs. (Photo courtesy of the National Oceanic and Atmospheric Administration)

Jun. 26, 2007

By Nancy Allen
Norfolk District

A U.S. Army Corps of Engineers team is fighting  nature to restore one of Virginia's most historic  natural resources, the native Crassostrea virginica, better known as the Eastern Oyster, which has been providing ecological and economic benefits to the mid-Atlantic region for more than 400 years.

As recently as 100 years ago, huge oyster reefs posed navigational hazards to ships in the area.  These historic populations, dubbed "Chesapeake Gold" by watermen, not only supported a booming oyster industry in Virginia and Maryland, but served the ecosystem by filtering water in the bay and providing habitat and food for other creatures.

Today, the oyster population in the Chesapeake Bay has been reduced to about 1 percent of its historic level due to years of over-harvesting, disease and loss of habitat. 

The mission of the Corps' Chesapeake Bay Oyster Restoration Program is the ecological restoration of the oyster and is focused on establishing sustainable breeding populations of native oysters in sanctuaries, free from fishing pressure. The program is being conducted in Virginia by the Corps' Norfolk District and in Maryland by the Corps' Baltimore District.

The Corps team was more accustomed to building projects and restoring wetlands or shorelines.  Restoring a living organism had never been attempted.  Norfolk District embarked upon its first oyster restoration effort in 2000 with a small-scale reef construction project in the lower Rappahannock River. Another project was completed in the Tangier/Pocomoke Sounds in 2003.

Corps staffers used lessons learned in the Rappahannock and Tangier/Pocomoke Sound projects as they began making plans for their next restoration effort in the Great Wicomico River.  The Great Wicomico project was initiated in 2004 and involved the construction of 64 acres of oyster reef habitat.  The reefs were then seeded with more than 12 million oysters.  The project marked the first large-scale restoration of an estuary subsystem as a single unit in order to "kick start" sustained natural oyster reproduction.

Now, nearly two years after the construction and seeding was initiated, the Corps is beginning to see results.  While spatset (the annual recruitment of young oysters to the current oyster population) this past year varied, some of the recently restored sites showed spatset as high as 6,000 spat per bushel, a level not seen in decades. 

The partners have now turned their attention to the site for the next restoration project, the historic Lynnhaven River in Virginia Beach, Va.  In the early part of the 20th century, Lynnhaven oysters were abundant and world-famous for their size and salty taste.  Orville and Wilbur Wright were said to have eaten Lynnhaven oysters before embarking on their historic first flight in Kitty Hawk, N.C.

The Lynnhaven River project will involve the initial construction of 111 acres of oyster reef habitat and the seeding of wild stock Lynnhaven oysters, which have shown to be more resistant to Dermo and MSX, diseases that have ravaged oyster populations in the bay.  The total project scope may restore approximately 430 acres of oyster reefs in the Lynnhaven River.

"The Lynnhaven is one of the best sites for restoration in the bay," said Dave Schulte, Corps biologist and technical team leader.  "We'll be building reefs where there haven't been reefs in a long time.  We have more information now, and we're using the best science."

The Lynnhaven River Project will offer the opportunity for the Corps and its partners to evaluate the use of different substrate material - in other words, creating oyster reefs not of fossilized oyster shell, but granite.   
 
Current research comparing fossil shell reefs to reefs constructed of alternative materials show that the survival rates of attached oysters are higher on granite reefs, and the reefs are in better condition.   

"We're taking a holistic look at oyster restoration," said Craig Seltzer, chief of the Environmental Analysis section in Norfolk District's Planning Branch.  "When you look at a river there are a number of factors that can impact the outcome.  We're paying attention to water quality, the effects of development, hydrodynamics."

The team hopes the Lynnhaven project will continue to provide more insight into the complicated task of reviving the native oyster in the bay. 

"We want to build sustainable oyster restoration projects," Schulte said, referring to reefs that will last beyond five or 10 years.  "Looking into the future, there are a lot of questions we need to answer, and the Lynnhaven project will be a good place to start.  The Corps is pushing for changes in the way oyster restoration is approached."