Colonies of baby oysters tethered to a Navy pier in Middletown thrived over the winter, and a research program testing whether they can help improve water quality in the Raritan Bay will be expanded.

The project by the NY/NJ Baykeeper and Rutgers University put the oysters in the bay's murky waters in October. About 90 percent of them survived the winter.

But Rutgers researcher Beth Ravit cautions that is probably an aberration, caused by the abnormally warm winter. She says 70 percent is closer to normal.

The state Department of Environmental Protection made the groups destroy an oyster project it had in Keyport two years ago due to concerns about poaching from dirty water. But the security of the pier at the Earle Naval Weapons Station ended those concerns.

(Copyright 2012 by The Associated Press.  All Rights Reserved.)