Seagrass Abundance Increases By 25 Percent In Maryland Coastal Bays

Annapolis, MD — The Maryland Department of Natural Resources (DNR), the Maryland Coastal Bays program, the Virginia Institute of Marine Scientists and the National Park Service has released a study showing that underwater seagrass abundance in Maryland and Virginia's coastal bays increased by 25 percent last year. This increase, from 10,916 acres in 2008 to 13,628 acres in 2009, shows that the bays continue to recover from a dramatic loss in 2005.

“The seagrasses are a great barometer of the health of the coastal bays, and while their increase is promising, our work isn’t done,” said Governor Martin O’Malley. “We must continue to reduce nutrient and sediment pollution, collectively and individually, to benefit seagrass restoration and ultimately the health of the coastal bays.”

Seagrass acreage is estimated through an aerial survey, which is done from late spring to early fall.

While this is a positive sign for the bays, only 50 percent of the seagrass goal was reached, indicating there is still work to be done to restore this vital habitat.

The total increase of 2,712 acres was driven mainly by the expansion of grasses in Chincoteague Bay, which increased by 2,165 acres to a total of 10,158 acres, a 27 percent gain. However, the 2009 Chincoteague acreage is still short of the bay high of 16,349 acres observed in 2001, and is only 40 percent of the goal.

Grasses in the Assawoman Bay increased by more than 300 acres, an increase of more than 50 percent, and at 871 acres, has reached a record high for this bay.

Newport Bay increased by 12 acres to 60 acres and Sinepuxent Bay increased by 241 acres, a 13 percent increase.

Isle of Wight Bay and St. Martin River remained virtually unchanged, but both are at the second highest acreage recorded in those areas since 1986.

The goal of 20,070 acres of seagrass was developed for the bays based on suitable bottom type and water depth by the Maryland Coastal Bays Program’s Scientific and Technical advisory committee.

Goal attainment is evaluated using the current 3-year average (2007-2009). Overall attainment of the seagrass goal was 42 percent compared to 71 percent in 2001. Goal attainment was highest in Sinepuxent Bay (63 percent) and lowest in Newport Bay (14 percent) and St. Martin River (5 percent). Other bays also had low goal attainment (Isle of Wight 28 percent, Assawoman 37 percent, and Chincoteague 40 percent).

"It’s good to see improvement in seagrass abundance; however, we have still not fully recovered from the losses suffered in 2005 when the bays lost 38 percent of the seagrass due to abnormally high water temperatures and poor water quality in some areas,” said Dave Wilson, executive director of the Maryland Coastal Bays Program. “The Coastal Bays Program will continue to work with local, state and federal partners as well as the farming and development communities to reduce nutrient and sediment pollution in order to reach our seagrass goal in the bays behind Ocean City and Assateague.”

Seagrasses are an indicator of clean water and provide essential food and shelter for many of coastal bays fish and shellfish including flounder, blue crab and bay scallops. Scallops, which require seagrasses in their early life, have not been observed in Chincoteague Bay since 2005 despite previous restoration success, according to DNR biologist Mitchell Tarnowski.

Low water quality is the biggest threat to seagrass recovery. Nutrient pollution fuels algae and seaweed blooms in the water which can block light to seagrass beds. Long-term monitoring by Assateague Island National Seashore shows that current trends in nutrient conditions continue to degrade in Chincoteague Bay. Sources of nutrient pollution include air deposition, farm fields, boating, development, septic fields, parking lots and wastewater treatment plants.

Marylanders can take simple actions to help protect water quality in coastal bays and seagrasses.

The Coastal Bays Nutrient Reduction Action Strategy recommends common sense approaches to nutrient reductions, such as minimal use of lawn fertilizers; following recommended farming practices; avoiding seagrass beds when boating; and using good boating practices that keep pollutants out of the water. Homeowners can have a particularly positive impact when they pump their septic tanks regularly, replace lawns with trees and native plants, build rain gardens, install rain barrels, diligently clean up pet waste and limit impervious surfaces on their property.

Additional information about the aerial survey and survey results is available at www.vims.edu/bio/sav/.

For more information about the Maryland Coast Bays Program, visit www.dnr.state.md.us/coastalbays/.

The Maryland Department of Natural Resources (DNR), which celebrated its 40th anniversary in 2009, is the state agency responsible for providing natural and living resource-related services to citizens and visitors. DNR manages more than 467,000 acres of public lands and 17,000 miles of waterways, along with Maryland's forests, fisheries, and wildlife for maximum environmental, economic and quality of life benefits. A national leader in land conservation, DNR-managed parks and natural, historic, and cultural resources attract 12 million visitors annually. DNR is the lead agency in Maryland's effort to restore the Chesapeake Bay, the state's number one environmental priority. Learn more at www.dnr.maryland.gov