SScientists hope to get Bay's oyster restoration rolling with reef balls
In one Bay experiment, the spheres had become so overgrown with oysters and colonizing organisms in just one year that
they had nearly become unrecogn
By Karl Blankenship
Faced with a declining supply of oyster shells and an increasing demand for oyster reefs, scientists
are exploring a new way to provide habitat: prefabricated oyster homes.
The homes in this case are “reef balls” made from concrete poured into fiberglass molds. When
popped from the molds and placed on the Bay’s bottom, they provide a raised, solid surface on
which oyster larvae, or “spat,” can attach and grow.
“The big picture idea is to explore alternatives to dredge shell for reef construction,” said Stephanie
Reynolds, a fisheries scientist with the Chesapeake Bay Foundation, which is conducting
experiments to see how hospitable reef balls are for oysters.
Restoring oyster habitat has been a goal of the Bay Program, but the primary building block for
oyster reefs—oyster shell—is in short supply. With oyster populations near a record low, little new
oyster shell is being produced.
As a result, most oyster restoration projects have been built on reefs made with ancient, buried
shells dredged from under the bottom of the Bay. But that supply is likely to come to an end
because of concerns over the environmental impact of the dredging operation.
“It’s been clear for a while that that was not going to be enough shell to get to the scale we wanted
to get to with native oyster restoration,” Reynolds said. “We were going to need other alternatives
besides just dredged shell.”
What’s unclear, though, is how big a role reef balls will play in meeting that need.
Most work with alternate reef material has been aimed at improving fish habitat. Parts of bridges,
piers—even Baltimore’s old Memorial Stadium—have been put in the Bay as fishing reefs. The debris provides solid surfaces that attract
mussels, clams, barnacles and vegetation, and also have cracks and holes to provide hiding places for small crabs and fish. That, in turn,
attracts larger fish—artificial reefs have long been popular fishing sites for anglers.
In recent years, reef balls were added to the mix. The creation of a Georgia-based nonprofit organization, the Reef Ball Foundation, the
balls are specifically designed to enhance aquatic habitats. The balls—used in restoration projects around the world—are hollow in the
center, with holes that allow marine life to move in and out.
“They have a larger surface area,” said Thomas Humbles, of Maryland Environmental Services, which oversees almost all of the reef
construction in the state. “The equivalent.....
