The Hogan administration has selected two Potomac River tributaries in Southern Maryland for large-scale oyster restoration efforts, one of them poorly rated by state biologists, while holding out hope of opening some state oyster sanctuaries for limited commercial harvesting.

Oysters cling to rocks on shoreline in upper St Mary's River, one of two Bay tributaries chosen by the Hogan administraiton for large-scale restoration of bivalve populations. (Dave Harp)

Natural Resources Secretary Mark Belton announced Friday that he’s recommending Breton Bay and the upper St. Mary’s River, both in St. Mary’s County, as the fourth and fifth Bay tributaries where Maryland would work with federal agencies to try to restore oyster populations. They are across the Chesapeake from the state’s other three waterways targeted for restoration — Harris Creek and the Tred Avon and Little Choptank rivers.

The announcement comes after more than a year of debate and deliberation over where Maryland should next focus its restoration efforts. Maryland and Virginia had each pledged to restore oyster populations in five tributaries under the federal-state 2014 Bay Watershed Agreement. But watermen have criticized the restoration work completed in Harris Creek and still under way in the other two Eastern Shore rivers. They also have chafed about the loss in 2010 of some of their more productive harvest areas when the state expanded its network of oyster sanctuaries.

Belton said he selected Breton Bay and the upper St. Mary’s because both ranked near the top when he asked members of the DNR’s Oyster Advisory Commission last year to identify where they’d like to next see restoration. Another factor favoring both water bodies is their proximity to one another, the DNR secretary said. He noted that the three Shore tributaries previously targeted for restoration, all tributaries of the Choptank River, are also close to each other.

The St. Mary’s River was among the top three vote getters when members of the 24-member advisory commission were asked to nominate future restoration tributaries, but it also got the highest number of votes against it. A 2016 report by DNR biologists analyzing the state’s oyster sanctuaries and public harvest areas found the upper river had the highest natural “spatfall,” or reproduction, of any water body in Maryland. It also concluded that oysters had grown in size in the 1,300-acre upper river area that had been designated as a sanctuary in 2010.

Southern Maryland watermen, unhappy about being barred from harvests in the upper St. Mary’s River, opposed its selection for large-scale restoration work. The river once yielded a substantial harvest, but not since MSX and Dermo, two oyster diseases, swept up the Bay in the late 1980s. 

Bob Lewis, executive director of the St. Mary’s River Watershed Association, said he was “elated” by Belton’s decision. The watershed group has been working since 2013 to restore oysters, spending more than $250,000 in donations and grants to build dozens of reefs on the bottom, using concrete and construction rubble. The reefs appear to be brimming with oysters.

“It appears as though the work we have done is sustaining itself and growing,” Lewis said. He said rebuilding the oyster population in the upper St. Mary’s is part of the association’s larger mission to restore the river to a state approximating the pristine conditions that English colonists found when they first settled in St. Mary’s County nearly 400 years ago.

Watermen, who've chafed over the upper St. Mary's River being closed to harvest in 2010, opposed designation of it for state-sponsored restoration. (Dave Harp)Robert T. Brown, president of the Maryland Watermen’s Association, had said earlier that he hoped the state would reopen a portion of that sanctuary and let watermen take juvenile “seed” oysters from it to plant elsewhere for later harvest. He said Friday that he had not seen the DNR announcement and reserved comment for later.

Belton said he wants to designate a seed oyster “study area,” to see if the sanctuaries are generating enough bivalve larvae to help repopulate reefs in harvestable waters.  He didn’t say where that area might be.

The DNR secretary’s other pick, Breton Bay, garnered the most support among DNR advisory commission members — and the least opposition — but DNR biologists in their 2016 review found that the oyster population in the sanctuary was only slightly above average, while natural reproduction had historically been “low and intermittent.”

The Chesapeake Bay Foundation welcomed Belton’s selection of the St. Mary’s river, but criticized Breton Bay. Alison Prost, the foundation’s Maryland executive director, said the upper St. Mary’s “is likely capable of developing a self-sustaining oyster population, and could act as a nursery for downstream areas where oysters can be harvested, as long as the upper river remains a sanctuary area off-limits to harvesting.”

But Prost said Breton Bay appeared to be a poor choice for restoration, calling it “a low-salinity area with a history of low oyster reproduction.

“It likely will be difficult and expensive to achieve successful restoration in Breton Bay,” she said, noting that DNR staff had acknowledged those deficiencies in a briefing to the oyster advisory commission.

Prost also questioned Belton’s announcement that the state would let the federal government underwrite restoration efforts in Breton Bay while the state undertakes restoration in St. Mary’s solely with state dollars. She noted that given the healthy oyster population already in the St. Mary’s, it may only require limited investment. But she said she found it “curious why DNR would decide at the outset not to leverage additional federal dollars for this project.”

The Harris Creek restoration involved a combination of state and federal funds, and the Tred Avon is being underwritten by federal funds, though those are in danger or running out. Only the Little Choptank restoration has been fully state-funded. Watermen, in seeking to reopen those sanctuaries for harvest, were told by state officials that the expenditure of federal funds on restoration barred any future commercial harvests.

Oysters have populated concrete and rubble reefs put in the upper St. Mary's River by the watershed association. (Dave Harp)A lower Eastern Shore tributary, the Manokin River, shared top votes as a restoration candidate in the polling of the DNR’s oyster advisory panel, which includes watermen, environmentalists, scientists and elected officials. DNR staff had identified the Manokin, along with the St. Mary’s, as the two Bay tributaries with the most promising potential to rebuild their oyster population with relatively little investment of public funds in reef construction and seeding with oysters spawned in a hatchery.

But Belton said he ruled out more restoration work in the Manokin or any other Shore tributary out of consideration for the complaints of watermen there that they were already bearing the brunt of the state’s effort to rebuild the Bay's oyster population, which has fallen to an estimated 1 percent of its historic level.

Bob Whitcomb of the Severn River Association expressed disappointment that the Annapolis area waterway was passed over. A 14-mile stretch of the river has long been a sanctuary and has seen a number of restoration efforts over the years, with hundreds of volunteers raising oysters from their docks and planting upwards of 750,000 baby bivalves annually in the river. Belton acknowledged the enthusiasm of Severn advocates, but said it lost out because of concerns about its suitability for large-scale restoration work and the desire to have two tributaries close together.

Belton did say the DNR plans to study and survey existing state oyster sanctuaries in the Severn and on the Lower Eastern Shore, specifically in the Manokin and Nanticoke rivers. He said state officials will draw up management plans for the rivers to determine how state investment and resources, including seed, shell and spat, could spur natural oyster growth and reproduction in them.

Finally, the DNR announcement said that the department intends to move forward with developing a “rotational harvest” system, where oysters are only allowed to be taken every few years, with the intent of giving the reefs time to repopulate with new bivalves. Early this year, the Hogan administration had floated the idea of opening portions of some of the state’s 51 sanctuaries to this new system of limited harvest. But the Maryland General Assembly blocked the move, barring any changes to sanctuaries until the DNR completes an assessment of the status of the state’s overall oyster stock. That study is scheduled to be completed by the end of 2018.