By Alex DeMetrick

BALTIMORE (WJZ) — In 1998, it was estimated there were 600 million oysters in Maryland waters. Now, a new population assessment finds that number has dropped to roughly half of what it was a decade ago.

“At the end of the last harvest season, it was estimated there were 300 million market-sized oysters, so, a lot of oysters still. It’s a big number but low relative to what it was before,” said Dr. Mike Wilberg with the University of Maryland Center for Environmental Science.

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Most are in the southern part of the bay. The north has very few. Dr. Wilberg with the UM Center spent 18-months on the assessment study.

“The oyster fishery historically is much, much larger than it is today, and I think it can get to be back to those levels,” Wilberg said.

He said this could be achieved through recovery efforts that raise larvae in the lab, attach it to empty shells and plant it onto existing and new reefs.

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One potential impact on oysters that was not part of the study is the deluge of fresh water that started pouring into the bay last spring and record rain that continues to fall, meanwhile, oysters need salty water.

“Freshwater could affect the reproduction for this year and could also have an effect on adult oysters that are out there,” said Ward Slacum, with the Oyster Recovery Project.

There are early signs freshwater is impacting oysters, even in the south bay. But those losses are for a future assessment.

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