Maryland planted nearly 750 million hatchery-reared oysters in the Bay this year, marking a new record in the state's oyster restoration efforts.

The University of Maryland Center for Environmental Science produced the spat at the hatchery at its Horn Point Laboratory on the Eastern Shore, which was expanded in 2004 to boost oyster restoration efforts.

Donald "Mutt" Meritt, who oversees the hatchery, said the record number was made possible by the increasing experience of the hatchery staff and improved Choptank River water quality used in the hatchery last year.

The hatchery spawns adult oysters collected by watermen to produce larvae.

The larvae are fed cultured algae until they are ready to set-the process whereby larvae permanently attach themselves to oyster shell or other solid substrates.

At Horn Point, that takes place in specially constructed tanks that are filled with cleaned oyster shells.

The "spat on shell" are then taken to restoration sites throughout the Bay for planting by the nonprofit Oyster Recovery Partnership.

Restoration sites are selected by the state Department of Natural Resources in consultation with the ORP, the U.S. Army Corps of Engineers, the National Oceanic and Atmospheric Administration, university scientists, the Maryland Waterman's Association and the Chesapeake Bay Foundation.

Next year, the lab plans to expand the area where oyster larvae are allowed to set and grow before being moved into the Bay.

With that expansion, the capacity of the lab's hatchery production is expected to increase to about 2 billion spat.

The previous record was 585 million spat produced last year. In contrast, the hatchery produced only 28 million spat a decade ago.