OCEAN CITY — A report released this week revealed vital underwater sea grasses in Maryland’s coastal bays decreased by an average of 35 percent in the last year, including losses exceeding 90 percent in many areas near Ocean City.
The report, released by the Maryland Department of Natural Resources (DNR), in partnership with the Maryland Coastal Bays Program, the Virginia Institute of Marine Scientists and the National Park Service, showed underwater grasses dropped from 13,863 acres in July 2010 to just 9,083 acres in May 2011, levels not seen since the early 1990s.
“These losses are troubling to the recovery of the bays,” said Maryland Coastal Bays Program Executive Director Dave Wilson. “We have lost nearly 20 years of sea grass recovery and the primary nursery for crabs and fish along with it. The Coastal Bays Program will continue to work with our partners to reduce nutrient and sediment pollution in order to improve water quality and reach our sea grass goal in the bays behind Ocean City and Assateague Island.”
Assawoman Bay saw a 96-percent loss, or 900 acres, while the Isle of Wight Bay lost 93 percent, or 483 acres. The St. Martin River lost its last 1.6 acres. Chincoteague Bay, with its vast fields of underwater sea grasses, saw a smaller percentage loss at just 27 percent during the period, but the greatest total acre loss at 2,756 acres. In total, sea grasses in the coastal bays declined from 13,863 to 9,083, for a net loss of 4,780 acres.
Sea grasses are an important indicator of clean water and serve as food and shelter for many fish and shellfish including flounder, blue crabs and bay scallops. The plants are also a vital food source for waterfowl during migration and over-wintering. Low water quality is the biggest threat to sea grass recovery.
Nutrient pollution fuels algae and seaweed blooms in the water, which can block light to sea grass beds. Sources of nutrient pollution include air deposition, farm fields, boating, development, septic fields, parking lots and wastewater treatment plants.
“The plants essentially succumb to the one-two punch,” said DNR Director of Tidewater Ecosystem Assessment Service Thomas Parham. “The heat alone doesn’t kill them unless combined with the already stressful conditions the plants are living in.”
DNR officials said nutrient pollution combined with volatile natural conditions in the bays was largely responsible for the sea grass die-off.
“Hotter summers and rising sea levels, along with increased storm intensity, could have devastating and far reaching environmental and economic impacts on the coastal bays ecosystem …,” said DNR Program Manager for Climate Policy Zoe Johnson.