St., Mary’s River Watershed Association 12th Annual Meeting guest speaker Dr. Lora Harris of Chesapeake Biological Lab.

St. George’s Island, MD – Oyster reefs have proven to be ‘amazing ecosystem engineers.’

The St. Mary’s Watershed Association hosted its 12th Annual Meeting at the Ruddy Duck on St. George’s Island.

The Chesapeake Bay as an ecosystem is ‘stuck,’ according to Guest speaker Dr. Lora Harris of the Chesapeake Biological Laboratory,

“Reductions in water-quality-killing nitrogen and phosphorus loading haven’t led to corresponding improvements. Dissolved oxygen is still low, making it hard for marine life to survive. That’s where the importance of oysters to filtering the Bay’s pollutants comes in,” said Harris.

Harris brought good news to the association members about the “amazing ecosystem engineers” that oyster reefs have proven to be. The association has been busy establishing oyster reefs in the St. Mary’s River.

Harris questioned how many oysters can be harvested and still retain the oysters’ filtering capability?

“Reefs work better than oyster bars because they add a vertical element which helps absorb the nitrogen in the water column. Reefs generally act as eventual stock for oyster bars,” said Harris.

Harris credited Richard Nixon with the enactment of the Clean Water Act which has led to a drastic improvement in water quality in the Chesapeake Bay and its tributaries. And she credited Maryland with leadership among the bay states.

“The Watershed Improvement Plans (WIP) is the latest technique of the Chesapeake Bay Program to improve water quality. It’s being pushed down to the counties for action,” said Harris. 

But Harris said so far those WIP guidelines don’t give credit for oyster reefs, as they should based on the latest science about their filtering capability.

The bay’s ecosystem has been severally impacted by nitrification and to a lesser extent phosphorus, from wastewater treatment plants and non-point source pollution from farms and septic systems, said Harris.

“Once you change an ecosystem, it’s pretty hard to get it to shift back,” she said in explaining why the oyster reefs play such a key role in that process,” said Harris.

Some ecosystems are easier to have pollution reversals–Tampa Bay being an example she said.

“But the Chesapeake Bay isn’t like that. The system has a stubbornness. More work needs to be done in identifying the oyster’s role in attacking that stubbornness,” said Harris.

The meeting was conducted by association President Joe Anderson and Executive Director Bob Lewis. During the meeting a new representative from St. Mary’s College, Chandler Wyatt, was elected to their board.

According to the St. Mary’s River Watershed Association website, http://www.smrwa.org/, “Since 2002, the St. Mary’s River Watershed Association has stimulated new efforts to protect and enhance the watershed in ways that also revitalize the economic, social, and cultural health of the community. With over five years of data from the St. Mary’s River Project, the Association was formed to establish a sustainable, reciprocally, beneficial relationship between the ecology of the St. Mary’s River and the communities that reside within the watershed.”

“In 2003, the Association completed a comprehensive management plan for the Hilton Run, a subwatershed of the St. Mary’s River. While completing this management plan, the group has done an enormous amount of work vital to the future of the Lexington Park area and its watershed.

“The Association strives to establish win-win partnerships that guide growth and preserve the natural, cultural, and economic characteristics of value to all citizens of St. Mary’s County.”

Contact Dick Myers at dick.myers@thebaynet.com