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ANNAPOLIS, Md. (NNS) -- A U.S. Naval Academy team of researchers and Navy divers completed a year of collecting oyster samples from the Severn River March 20 as part of an ongoing effort to study and restore oyster populations in the Chesapeake Bay watershed.

The team helps rejuvenate the declining oyster population by monitoring water quality and testing the collected samples.

The project was initiated two years ago, when a group of oceanography and ocean engineering faculty and staff working independently on Chesapeake Bay-related issues saw the Army Corps of Engineers were reconstructing local oyster reefs.

The USNA group contacted the Army's engineers to suggest that the Naval Academy could play a role, said ocean engineer Louise Wallendorf, who works in the academy's hydromechanics laboratory.

Oyster larvae need a hard surface on which to attach, so they can change to young oysters called "spat," and grow. Normally larvae settle on the shells of oysters that make up the bay's reefs, but overharvest and changes in the oyster reefs have led to a dramatic decline in oyster populations.

Oyster restoration involves building reefs made of oyster shells, granite, recycled concrete and slag and placing them in known oyster breeding spots, including an area in the Severn River near the Naval Academy yard.

The Academy works with researchers from the University of Maryland who hatch oyster larvae and grow the spat on shell, and the Oyster Recovery Partnership which coordinates placement of the oyster spat on the Army's artificial reefs, said Wallendorf.

The Naval Academy Sailing Center also became involved, supplying boats for the researchers to place water quality instrumentation and the Navy divers to collect oyster samples from the reefs.

"What we do on each dive is harvest a certain amount of oysters from each type of reef," said Navy Diver 2nd Class Casey Mrozek, of Lake Zurich, Ill. "The Academy team then conducts biological tests to determine which areas promote the best growth rates."

Cecily Steppe, associate professor in the Oceanography Department, examines the maturity and gender of the oysters under microscopes and compares it to measurements of the water's salinity, temperature and dissolved oxygen at each reef site. This helps determine the oysters' ability to survive and reproduce. Reports are then sent to the Army Corps of Engineers for evaluation.

Only since diving for the project did Mrozek realize how important the oyster culture is to the community.

"It's cool to know that you're part of something that's helping the environment and the whole ecosystem around here," he said. "Participating in projects like this shows that the Navy is not just concerned about defense. We're concerned about the environment that we need to live in and sustain ourselves."

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