HOW DOES WATER QUALITY, PHYSICAL SETTING, AND COASTAL DEVELOPMENT AFFECT OYSTER SPAT SETTLEMENT IN SOUTHERN GEORGIA SALT MARSHES?
Much of the United States' East Coast has experienced a decline in eastern oyster (Crassostrea virginica) landings since the early 1900s. In Georgia, this decline has been linked to overharvesting, disease, storms, and alterations in both water quality and natural flow regimes. Although past research has provided important information about the distribution of Georgia oyster reefs, microsite differences of spat settlement in relation to water quality, sediment composition, and coastal development have not been adequately addressed. A study was begun in March 2020 to determine if oyster spat settlement is correlated with these parameters. Three sites were chosen on Sapelo Island and three sites on Jekyll Island based upon proximity to development and location along the upland-estuary-sound gradient. Oyster spat settlement racks were established at each site. Tiles were collected every six weeks and number of oyster spat along with other biofouling organisms such as barnacles (Chthamalus fragilis) were determined. Additionally, water quality and sediment composition were measured during each collection period. The highest oyster spat settlement occurred in open sites with relatively high salinity, low turbidity, and high nitrogen levels. The highest barnacle settlement occurred in upper tidal creeks with relatively low salinity, high turbidity, and low nitrogen levels. Implications of this correlational analysis are discussed as well as future in-field manipulation experiments. This study is a preliminary attempt to develop a model for identification of potential oyster reef restoration sites.
MGA Natural Sciences Department
Cruse, Kara*; Morris, Kyra*; and Hancock, Thomas
"HOW DOES WATER QUALITY, PHYSICAL SETTING, AND COASTAL DEVELOPMENT AFFECT OYSTER SPAT SETTLEMENT IN SOUTHERN GEORGIA SALT MARSHES?,"
Georgia Journal of Science, Vol. 80, No. 1, Article 50.
Available at: https://digitalcommons.gaacademy.org/gjs/vol80/iss1/50