The Effect of Aquaculture Gear and Tidal Zone on the Growth and Shape of the Oyster Crassostrea Virginica during a “finishing Period” in Chesapeake Bay

Title of Thesis: THE EFFECT OF AQUACULTURE GEAR AND TIDAL ZONE ON THE GROWTH AND SHAPE OF THE OYSTER CRASSOSTREA VIRGINICA DURING A “FINISHING PERIOD” IN CHESAPEAKE BAY. Laura Landis Thomas, Master of Science, 2016 Thesis directed by: Assistant Professor, Louis V. Plough, Marine Estuarine Environmental Science Research Professor, Jeffrey C. Cornwell, Marine Estuarine Environmental Science This study investigates how gear type and increased wave action as a result of tidal zone location, influenced the shape and weight of Crassostrea virginica during a “finishing” period in Chesapeake Bay. For these experiments, oysters were deployed in three different gear treatments in the intertidal zone: bottom cages, OysterGroTM floats, and rack and bag, and a bottom cage deployed in the subtidal zone as a control treatment. Shell length, width, height, total weight and wet meat weight were measured each month from August to December 2015 and an index of shell shape relative to an idealized 3-2-1 ratio of length, width, and height was calculated. OysterGroTM floats produced significant increases in total weight and wet meat weight. Also, OysterGroTM floats showed less deviation from the ideal 3-2-1 ratio, while only one other treatment (intertidal bottom cage) differed from the control (subtidal bottom cage).