Water Resources Research Act Program

Details for Project ID 2008DE126B

Effects of Water Quality on Oyster Growth (Crassostrea virginica) in the Floating Oyster Aquaculture Gear in Delaware's Inland Bays

Institute: Delaware
Year Established: 2008 Start Date: 2008-03-01 End Date: 2009-02-28
Total Federal Funds: $3,500 Total Non-Federal Funds: $7,000

Principal Investigators: Aaron Gibson, Gulnihal Ozbay

Project Summary: The dramatic decline of the Eastern oyster (Crassostrea virginica) population in the Mid-Atlantic has been well documented as a result of overharvesting, habitat degradation, reduced water quality, and increased mortality from Dermo and MSX diseases the late 1800s. Subsequently, restoring oyster populations for their ecological and commercial contribution to the health and viability of coastal estuaries is a common priority and activity among community-based estuary programs. Delawares coastal lagoons, known locally as inland bays, have been experiencing the impacts of chronic eutrophication and sediment erosion resulting from several decades of development and sustained nutrient input from within the surrounding watershed. The cumulative impact of these anthropogenic effluents has degraded water quality and reduced the diversity and abundance of various species of fishes, invertebrates and submerged aquatic vegetation. Oysters provide ecological services by filtering sediments and algae from the water column, increasing water clarity, and removing nutrients such as nitrogen and phosphorous from eutrophic waters. By placing oysters in floating cages in the canal systems with the Inland Bays, growers intend on using the oysters to improve local water quality and clarity along with providing broodstock to help restore populations to the estuary. Oyster reefs are known as a valuable yet neglected component of estuarine ecosystems, providing a unique habitat for many ecologically and economically important species. Oyster aquaculture can provide many of the same services as oyster reefs. This study aims to monitor effects of water quality on oyster growth and survivorship in selected oyster gardening sites in Delaware's Inland Bays. Results from the three bay areas will be compared to determine which sites produce better oyster growth and/or survival and which sites had the most improvements to the habitat and which sites may warrant closer attention for restoration efforts in the future.