Thursday, December 5, 2013
PORTLAND — Coastal development and pollution are contributing to the decline of a common sea grass that supports birds, fish and other life along the coast of New England and eastern Canada, scientists said Tuesday.
More than 100 scientists and regulators from the United States and Canada gathered Tuesday morning in Portland for the start of a two-day meeting on the status of the region's eelgrass and how to protect it.
Eelgrass, the long, bright green blades of grass that can be seen in shallow bays and estuaries at low tide, provides food and habitat for everything from flounder to lobsters and helps control pollution and erosion.
Because it grows only in clear water, shrinking eelgrass meadows are considered a warning sign of less visible problems, such as pollution.
''(Eelgrass) tells us what the whole ecosystem is doing, and it's very important to the maintenance of the whole coastal zone,'' said Fred Short, a University of New Hampshire scientist who delivered Tuesday's keynote address.
Short and other scientists have been tracking eelgrass trends over the past 10 to 20 years using a combination of aerial photos and underwater video. Researchers from New York to Canada said they have measured declines along some parts of the coast of as much as 80 percent to 90 percent. Some eelgrass beds are gone entirely, they said.
Maine's eelgrass resource appears to be the most stable, with growth in some areas -- including Casco Bay -- making up for dramatic declines in Penobscot Bay.
''Penobscot Bay is definitely a problem,'' said Seth Barker, a marine biologist with the Maine Department of Marine Resources.
Though Barker said he doesn't know the cause of the decline there, the culprit is most often pollution that clouds the water so that the grass doesn't get enough sunlight.
''Water quality is one of the primary issues,'' Barker said.
Nitrogen that washes off fertilized lawns and farms, leaks out of septic systems and sewers and flows down rivers in sediment is considered the biggest cause of the decline.
Nitrogen affects the eelgrass directly and feeds blooms of other algae that cloud the water and block light.
Some localized declines have been linked directly to sewers or new home development, the scientists said.
''We're dumping huge amounts of nitrogen,'' Short said.
The decline in eelgrass is a growing political issue as well.
Scientists from up and down the coast said the meeting in Portland, and hearing of the common experiences, is a step toward a more coordinated monitoring and management effort.
''We're seeing pretty much a decline across the line,'' Short said.
Staff Writer John Richardson can be contacted at 791-6324 or at: