Shellfish decline in N.H.
The Associated Press | October 16,2006
DOVER, N.H. — Oyster and clam populations are at record lows, but the water in the state's estuaries is getting cleaner, according to a new report by the New Hampshire Estuaries Project.
The number of oysters that can be harvested has fallen 93 percent since 1993, due primarily to two devastating diseases, according to the "State of the Estuaries" report, which looked at areas including Great Bay and Hampton-Seabrook Harbor.
The report also found that the number of harvestable clams was 31 percent below the state average of 8,500 bushels per year.
However, toxic contaminants in shellfish have decreased 17 percent to 68 percent since 1990, depending on the species, the report found. Over the same period, concentrations of bacteria present during stretches of dry weather have fallen 73 percent.
The Estuaries Project is part of the federal Environmental Protection Agency's National Estuary Program, set up under the federal Clean Water Act. The report is updated every three years; the latest update will be released formally on Oct. 27.
Phil Trowbridge, the report's primary author, said he is most worried about increased nitrogen in the water, which can cause large algae blooms that suffocate other organisms by depriving them of oxygen. Such blooms have devastated large areas of Chesapeake Bay in Maryland and Virginia, he said.
"Our report demonstrates a clear increasing trend in nitrogen that, if not curbed, may cause similar problems here," he said.
Trowbridge also is concerned about increased development in the coastal watershed, because it means more roads and parking lots. Runoff from those surfaces adds more oil and sediment to lakes, streams and estuaries, he said.
Ray Grizzle, an associate professor of zoology at the University of New Hampshire, said the decline in the oyster population was caused by two devastating diseases, harvesting, sediment build-up and a lack of hard surfaces where oysters can attach. He's encouraged by the lower levels of toxic chemicals, however.
Most clam and oyster harvesting in the state is recreational, making it hard to get federal money to help restore shellfish populations, he said.
"If we were in Maryland or Virginia, we'd be talking about hundreds of jobs and millions of dollars in the budget," Grizzle said.
The focus on commercial fisheries is shortsighted, he said. Shellfish are critical to the overall health of estuaries because they provide food for other creatures and filter the water, said Grizzle, who has been buying oyster larvae bred for their disease resistance and introducing them to coastal waters.
Greenland Conservation Commission Chairman Rick Mauer said the periodic estuary reports are helpful because they give towns "added firepower" for evaluating the environmental impact of proposed subdivisions, as well as existing developments.
"It's basically a report card so we can see what we're doing right, what we're doing wrong and how we can make things better," he said.