Water Resources Research Act Program

Details for Project ID 2007DE108B

Viability of a Freshwater Mussel (Elliptio complanata) as a Biomechanical Filter in Aquaculture Ponds

Institute: Delaware
Year Established: 2007 Start Date: 2007-06-01 End Date: 2008-02-28
Total Federal Funds: $3,500 Total Non-Federal Funds: $7,000

Principal Investigators: Gulnihal Ozbay, Oluchi Ukaegbu

Abstract: Many freshwater aquaculture facilities utilize earthen ponds for the growth of their commercial products. The production and livelihood of these facilities depends on the increased growth of the species being harvested. This is usually done through manufactured foods or increased feeding. In fish, only 30% of the phosphorus and 50-70% of the nitrogen in the feed are retained, even if all feed is consumed. This is cause for concern because of the possible eutrophication effects that nitrogen and phosphorus can have on the system. Most solutions used today involve removing excess nutrients from diets instead of finding ways to handle the excess amounts of nutrient produced by the organisms. Currently, eutrophication events in aquaculture are kept in check through a combination of chemical and mechanical treatments, which is quite costly and account for a large percentage of the total cost of running an aquaculture system. There are also concerns about the use of chemicals in the rearing of food fish. In both marine and freshwater systems bivalves have been proven to be an inexpensive method for removing suspended solids, dissolved nutrients, and in controlling algal growth through suspension feeding. This makes them an ideal candidate for use as a biological filtration system. The major objective of the proposed research is to investigate the effects of the bivalve E. complanata on pond water quality and effluents. Additional objectives include investigating the phytoplankton and organic matter filtering ability of E. complanata under laboratory and in production ponds; comparing fish production and health with and without the presence of E. complanata, and monitoring the in-pond growth and health of E. complanata.. Should our study prove that mussels improve water quality, it is conceivable that aquaculture ponds could potentially serve as a grow-out facility for lab reared mussels before reintroducing them to their natural environments.