Science Serving Maryland's Coasts

Julie Palakovich Carr, Boston University

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Project Title: 

Effect of a Restored Oyster Reef (Crassostrea virginica) on Water Quality in a Subestuary of the Chesapeake Bay


Water quality over and downstream of a restored eastern oyster reef (Crassostrea virginica) was compared to upstream of the reef. Total suspended solids, chlorophyll a, urea, and ammonia, as well as the abundance of different size classes of phytoplankton were measured from surface and bottom waters along a transect upstream, over, and downstream of the reef. There was no significant difference in any of these parameters over the reef as compared to upstream of the reef or upstream versus downstream of the reef. This is likely due to the heavy sediment and nutrient loads that enter the estuary via farm runoff, thereby masking any effect the oysters have on water quality. These results suggest that other means of improving water quality in the estuary, such as introduction of a nonnative oyster or policies controlling runoff and sediment loads, should be investigated further.