Chesapeake Bay Grasses Dwindle

By Sarah Polus, CAPITAL NEWS SERVICE

Bay grasses not only provide important habitats for wildlife, but experts are learning that healthy beds can be an important line of defense against severe coastal storms.

However, scientists are finding significant declines in the health and diversity of grasses found in the Chesapeake Bay.

According to the Maryland Department of Natural Resources Program Chief Lee Karrh, there are at least 17 species of grasses in the bay, in various locations based on the water’s salt content.

Wild celery and stargrass like to grow in fresher waters of the northern region of the bay, widgeon grass is commonly found in the middle regions, and eelgrass prefers areas of high salt content, such as the lower region near the Virginia state line.

“What’s very concerning is [in the lower part of the bay] we’re losing a lot of eelgrass,” Karrh said, attributing this change to heat stress in the summers. Karrh said 2005 and 2010 were "very warm summers that impacted the eelgrass more so than other species," noting that eelgrass is very slow to recover.

Other parts of the bay—especially the middle regions—are experiencing a decline in grass species as well, and a general loss of diversity, Karrh said.

The decline of bay grasses is concerning to scientists, like University of Maryland Atmospheric and Oceanic Science Professor Raghwho Murtugudde, who said that the grasses are natural filters against strong storms and nutrient and sediment pollution from land, and they provide habitats for everything from oysters, crabs and small fish to microbes, bacteria, insects and birds.

"They are critical for maintaining required levels of oxygen for all living species," Murtugudde said.

Underwater grasses also help reduce wave strength.

"Good grasses will reduce coastal erosion…they have a nice buffering capacity," said Rich Batiuk, associate director at the U.S. Environmental Protection Agency’s Chesapeake Bay Program office. Batiuk noted that areas in Maryland with healthy bay grasses saw less shoreline damage after strong storms in recent years.

New York City recently decided to restore its Jamaica Bay marshes for coastal defense after Sandy struck.

"We don’t need to wait for a disaster to learn these simple lessons," Murtugudde said.

According to Murtugudde, bay grass revival requires humans to reduce their pollution and runoff, which can be achieved by limiting nutrients used on lawns and agricultural farms, and using permeable paving materials.

“People who live in houses can do some simple things,” added Batiuk, like creating rain gardens, placing rain barrels under drain-spouts to prevent runoff, and making smart transit choices, like driving low-emission cars and taking public transportation.

Individuals' efforts can have “small but incrementally important impacts," Batiuk said.