Environment

Checking up on oysters

Trip shows how well planted shellfish are growing

By PAMELA WOOD, Staff Writer
The Capitol, Published 11/23/09

Pamela Wood - The Capital Capt. Karl Willey empties a bag of oysters collected Friday from the Severn River on the deck of the Patricia Campbell, the Chesapeake Bay Foundation’s restoration boat. The CBF worked with divers from the National Oceanic and Atmospheric Administration to monitor the health of oysters on restored reefs in the river.

One of the troubles with Chesapeake Bay oysters is that you just can't see them.

Fish splash around and will bite on a good lure. It's easy to chicken-neck for crabs.

But oysters - whether they are natural oysters or ones planted for restoration - are all the way at the bottom of rivers, far below the often-murky water.

"It's not like a garden, where you can see it grow," said Chesapeake Bay Foundation scientist Stephanie Reynolds, who was part of an expedition on the Severn River last week to check up on some oyster restoration sites.

The team was comprised of CBF employees and divers from the federal National Oceanic and Atmospheric Administration. The team took CBF's oyster restoration boat, the Patricia Campbell, to three sites on the Severn on Friday.

What the divers found was impressive: large, healthy, living oysters.

At each site, the divers went overboard and used a square frame made out of pipe to measure out a specific area. The square is one-third of a square meter, which is a little more than 1 square foot.

The divers picked up all the oysters within the frame, put them in mesh bags and handed them over to Reynolds and Karl Willey, captain of the Patricia Campbell.

Reynolds and Willey spread the oysters out on the ship's deck and counted and measured them. This gave a general idea of the quantity and quality of the oysters on each reef.

"Twenty-four alive, eight dead," Willey said to Reynolds, who was recording the information on a laptop computer.

"Nice," she replied.

Oyster restoration is an evolving science, and monitoring data can help scientists know if they're on the right track with their restoration techniques.

The University of Maryland has estimated that when baby oysters - called "spat"- are planted in the bay, usually about half of them die within the first year.

But Willey said monitoring is showing that in the Severn at least, survival is somewhat better than 50 percent.

Last week's monitoring also showed that oysters are doing well on a reef just off of Asquith Creek that was created with rubble from the Bay Bridge redecking project.

The Asquith Creek reef has been planted with oysters the last two years by the bay foundation and the nonprofit Oyster Recovery Partnership.

But there also is not-so-good news. While the planted oysters are doing well, there is still almost no evidence of natural oyster reproduction, also called "recruitment."

That means that the mature oysters just aren't successful in creating baby oysters.

"What we really want to see is natural recruitment, which we haven't seen," Willey said.

The bay foundation tries to get out to all of the reefs it has worked on annually during this time of year. The foundation is one of several government and nonprofit groups working to restore the Chesapeake Bay's native oyster, which has almost been wiped out due to disease, pollution and past overharvesting.

For Willey, the monitoring a nice reward after a long, hot season of moving and planting oysters with the Patricia Campbell.

"It's a great time of year to come out and see the fruits of your labor," he said.

(Revised Nov 2009)