Researchers think oysters could help clean up Chesapeake Bay.
The Washington Post reported Sunday that a reef seeded with oysters by the state of Maryland — about 130 oysters per square meter — removed 20 times more nitrogen pollution from such stuff as home lawn and farm fertilizer in one year than a nearby site that had not been seeded, according to a recently released study.
Lisa Kellogg, a researcher for the Virginia Institute of Marine Science who led the 4-year study, told the Post that oyster reefs could potentially remove nearly half the nitrogen pollution from the Choptank River on Maryland’s Eastern Shore. A wider restoration could help clean Chesapeake Bay, where the Choptank and other major rivers drain.
It is a huge deal, Kellogg told the Post.
Man-made nitrogen pollution is part of a one-two punch that creates oxygen-depleted dead zones that have plagued the bay. At one time, when oyster reefs were so mountainous and plentiful that European explorers complained about navigating around them, the Chesapeake was crystal clear.
Oyster reefs are inhabited by more than 24,500 nitrogen-filtering marine animals in addition to oysters, such as mussels, clams and sea squirts. Excessive harvesting of oysters, combined with farm and urban pollution, depleted the bivalves. Then in the 1980s two diseases decimated the remaining stock of oysters in Maryland and Virginia.
Oysters in those two states are experiencing a modest recovery because of the restoration and farming known as aquaculture.
Kellogg and her fellow researchers wanted to show that oyster reefs could greatly improve water quality and are worth the millions of dollars being invested in their restoration.