This summer, the Army Corps of Engineers, Norfolk District, is rebuilding 12 acres of sanctuary reefs in the Great Wicomico River that failed because they were not tall enough and suffered losses due to poaching.
Restoration reefs totaling 85 acres, were built in the Great Wicomico in 2003-2004 to serve as part of a multiyear project undertaken by the Corps, the Virginia Marine Resources Commission, and the Virginia Institute of Marine Sciences. At the time, the Great Wicomico project was hailed as the largest oyster restoration project in the world. Though the reefs were performing well, with heavy set of spat (oyster larvae) and average life spans of five years, in 2011 the Corps started to report losses due to poaching. But the construction design also had flaws.
“We have since determined that we need to build ‘high relief’ reefs (greater than 12 inches) to achieve a sustainable and healthy oyster reef,” said Patrick Bloodgood, representative for the Norfolk District of the Corps. Oysters on the shorter reefs were not healthy enough to be successful, based on criteria set by the Corps and restoration partners, including the National Oceanic and Atmospheric Administration, VMRC, VIMS and the Chesapeake Bay Foundation. Oysters did not grow as well on the shorter reefs because heavy sediment in the river smothered the beds.
Sanctuaries in the Great Wicomico and other Virginia tidal rivers are set aside to protect oyster reef habitat and the diverse and multiple aquatic organisms that thrive there. The reefs establish a hard bottom substrate that can stabilize river sediments. Restoration reefs can increase the oyster populations of public or private oyster beds close by because larvae from spawning oysters on the reef will set on nearby reefs as well as the restoration reef itself. Restoring oyster beds is also a key component of Chesapeake Bay restoration because of oysters’ ability to filter large amounts of seawater.
But sanctuaries are also difficult to guard, especially because they are so close to the public grounds in the river. The Corps said in a statement that it is “currently working in partnership with VMRC to ensure that security and enforcement measures are in place to deter future poaching of oyster sanctuaries.”
VMRC, which regulates and enforces oyster harvesting in Virginia, has been cracking down on oyster poachers for the last several years. Starting July 1, VMRC may revoke commercial and recreational fishing licenses of convicted poachers for up to five years (it had been two years), fine offenders up to $10,000, and place liens on poachers’ vessels or vehicles if the fine goes unpaid for six months.
The new restoration effort will cost $2 million, including the cost of recovering fossilized shell from the James River to serve as substrate in building the reefs. Oyster shell for reef building and restoration is in short supply around the Bay as spat-on-shall aquaculture is becoming increasingly popular. But VMRC’s Jim Wesson said that Tribell Shoals below Jamestown has been a regular source of shell since 2000. VMRC has also been active in the Great Wicomico with its own projects, said Wesson, who heads VMRC’s Oyster Replenishment Program.
“We’ve gone in and cleaned the areas that the Corps is going to restore,” said Wesson, removing live oysters and moving them to new locations. Some oystermen pay VMRC to dredge smaller oysters from pubic grounds and move them to other tributaries to give them a better chance to grow to market size. The Corp’s reef project is expected to be completed by the end of July.
The Chesapeake Bay Watershed Agreement oyster outcome aims to restore and protect oyster reefs in 10 tributaries by 2025. Six tributaries have been selected for large-scale oyster restoration, and restoration work has begun in four of these tributaries. The six tributaries are Harris Creek, the Little Choptank River and the Tred Avon River in Maryland, and the Lynnhaven, Lafayette and Piankatank rivers in Virginia.
After declining for more than a century, oyster populations plummeted in the 1980s due to overharvesting, disease and poor water quality. Since then, scientists have developed strains of disease-resistant oysters, some of which are able to hold off the diseases long enough to grow to legal length for harvest. The Corps’ oyster restoration efforts have been ongoing in Maryland since 1995 and in Virginia since 2000. The Corps, VMRC, and Maryland Department of Natural Resources developed the 2013 Chesapeake Bay Native Oyster Restoration Master Plan, which recommends large-scale restoration in sanctuaries. The plan identified 14 tributaries in Maryland and 10 in Virginia that would be suitable for large-scale restoration. The restoration target for the Great Wicomico is 100 to 400 acres.
Since 2001, the Corps has constructed sanctuaries in the Rappahannock River, Tangier/Pocomoke Sound, Great Wicomico River and the Lynnhaven River. Construction of 20 acres of sanctuary reefs in the Piankatank River is currently underway in partnership with The Nature Conservancy and VMRC.