Scouring Raritan Bay suitable for oyster habitat - WSJ.com

HIGHLANDS, N.J. — There once were so many oysters in the Raritan Bay that nautical charts from the early 1900s listed huge mounds of them as navigation hazards.

When explorer Henry Hudson sailed into the region in the 1600s, oyster reefs covered 350 square miles, spanning from Sandy Hook all the way to Ossining, N.Y., on the Hudson River.

But pollution, disease, over-harvesting and a buildup of silt in the waterways nearly wiped out the species in the Raritan Bay.

A plan by the U.S. Army Corps of Engineers to restore the ecological health of the estuary includes re-establishing oyster colonies. But a group of scientists and environmentalists wants to find out if it can actually be done.

A team of volunteers led by Beth Ravit, who teaches environmental science at Rutgers University, and the NY/NJ Baykeeper Environmental group is studying conditions in the bay to see whether, and where, new oyster colonies might thrive.

"Oysters filter a lot of water," Ravit said. "If they can't eat it, they consolidate it into a pellet and spit it out. But now it's a hard pellet that will sink to the bottom instead of being suspended in the water. They clean the water and change the properties of the entire water column."

Last year, the state Department of Environmental Protection forced Baykeeper to remove and destroy 30,000 oysters from the bay because New Jersey was not complying with patrol requirements to make sure no shellfish were being harvested from contaminated waters. The U.S. Food and Drug Administration threatened to shut down New Jersey's shellfish industry, and the state ordered all research-related commercial species of shellfish be removed from contaminated waters.

"We will not accept the bay's poor water quality," said Debbie Mans, Baykeeper's executive director. "So while the oyster ban is in place, and nothing is being done to heal the bay, we are doing valuable alternative research such as this mapping project."

She said the group has identified a new potential site for oyster research, off the Earle Naval Weapons Station in Middletown, if necessary approvals can be granted.

Friday's research expedition near the station's waters was to check water quality and conditions on the bay's floor. Concerns include whether other animal colonies such as hard or soft clams have already set up shop in a particular site, Ravit said.

"We don't want to displace one species to help another one," she said.

So far this year, volunteers with the project have walked about 20 miles of the Raritan's coastline and ventured into the shallow waters to document conditions. Data is still being considered, but a preliminary review indicates one promising spot is at Conaskonk Point in Union Beach, Ravit said.

"That's where the original beds were, and it looks like the conditions there are pretty good," she said. "There also may be some areas near Sandy Hook."

As with real estate, a crucial concern with oyster beds is location, location, location.

"We've had a very missed experience with survival," she said. "In some places it's 70 percent; in others it's five. It's really very site-specific."

Baykeeper is growing small oysters, called spat, in large tanks on the bay's shore, to be used in a future research project if the ban is lifted.

The mapping project is expected to be completed by the end of September. Eventually the mapping project will be expanded to include Perth Amboy, South Amboy, Newark Bay and other areas.