NEWMARKET — Oysters will begin to make a significant return to the waters of Great Bay.
The Nature Conservancy’s New Hampshire Chapter (TNC) and University of New Hampshire scientists along with other partners are working with local marine contractor, Riverside & Pickering of Eliot, Maine, to construct 2.5 acres of oyster reef at the mouth of the Lamprey River.
The barge crew will be placing 225 tons of clean, recycled surf clam shell on the river channel bottom in carefully arranged plots that form a living reef. The thin layer of shell acts as the foundation for oyster spawn to set on naturally, and it provides a base for thousands of disease-resistant juvenile oysters raised at a UNH hatchery by Dr. Ray Grizzle. The project is the largest of its kind north of Cape Cod.
“Vast reefs of live oysters once covered the bottom of the Great Bay Estuary, filtering out excess nutrients, providing habitat to a diversity of fish, and offering recreational harvest to generations of locals,” said Daryl Burtnett, TNC Director. “But due to pollution, disease and overharvest, we have lost 90 percent of our reefs. Using surf-clam shell from offshore draggers, locally recycled oyster shells, hatchery set oysters and volunteer-raised juveniles, we are rebuilding the oyster reefs of Great Bay acre by acre.”
In total, 100,000 square feet of shell reef will be rebuilt in an area once teeming with oysters, but now covered only with silted bottom and scattered shells. Once the annual spawn is over and the hatchery work is complete in the fall, about 500,000 new oysters are expected to reside on these new reefs. And the reefs are in areas closed to harvest so they can act as spawner sanctuaries for the rest of the estuary.
“Oysters may be Great Bay’s best hope for sustainable recovery of our estuary,” said Dr. Ray Konisky, Director of Marine Science for TNC. “These resilient animals are amazing at water filtration, and right now we have a major problem with excess nutrients. Towns are grappling with meeting the necessity to remove more nutrients from their wastewater. We want to complement those efforts by re-establishing healthy oyster reefs. So we’re rebuilding oyster reefs as a way to help nature bring the estuary back into balance.”
TNC and UNH have formed a partnership to restore oyster reefs around the region. Construction techniques with surf clam shell were started with a pilot study in 2009, expanded to a more than an acre in 2010 in the Oyster River in Durham, and doubled again in 2011 with the work at the Lamprey River site.
Now in its sixth season, the N.H. Oyster Conservationist Program engages about 25 homeowners around the bay who raise juvenile oysters on their docks for the restoration reefs. The UNH Docents provide labor for some of the shell handling duties. The Coastal Conservation Association operates a N.H. and Maine oyster shell recycling program for restaurants that recovers about five tons of shell per year for hatchery operations. Community support is an integral part of the restoration program.
Funding for oyster restoration comes from a variety of federal, state, and private sources. Lead funders include the Piscataqua Region Estuaries Partnership, NOAA Restoration Center, Natural Resources Conservation Service, State of N.H. Conservation License Plate Program, The Davis Conservation Foundation, and many private donors.
More information about reef construction and the Oyster Conservationist Program, visit www.nature.org/nhoysters. For information about the restaurant shell recycling program, go to www.ccanh.org. For marine contracting services, call Lori at Riverside & Pickering at (603) 502-0578.
Copyright (c) 2011, Foster’s Daily Democrat, Dover, N.H.
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