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blooms. Seagrass require Tight for survival and growth. As of 2017, northern portions of the County have approximately 1,239 acres, middle portions have approximately 669 acres, and southern portions have approximately 1,074 acres of seagrass. These acreages are higher than the majority of reported acreages for the rest of the Northern Indian River Lagoon. It will be important to note in future research the location and extent of seagrass beds in comparison with areas and amounts of nutrient fluxes. It will also be important in the future to note how harmful algal blooms have correlated to seagrass coverage within the County. While seagrass is mapped well within the County, we do not fully understand the species variation genetics of the individual seagrass beds; if monoculture beds are emerging, or if we have a genetic variety of types of seagrasses present. The Lagoon may also benefit in studying areas that had historical seagrass beds, but do not currently, and possibly looking into utilizing these areas for seagrass planting projects. In order for these projects to be successful, water quality, sediment quality, and shelter from strong currents must be sufficient for fragile new growth to survive in these areas where robust natural growth has died off. Filter feeders, such as oysters and clams, play an important role in water column filtration throughout the Lagoon. Adult oysters in our portion of the Lagoon are able to filter between 10 to 20 gallons of water every day. Oysters filter sediments, detritus, small phytoplankton, and particulate -bound nitrogen and phosphorus from estuarine waters. Changing conditions in the Lagoon are impacting filter feeders through poor water quality, poor sediment quality, harmful algal blooms, changes in food types and availability, changes in predator populations, salinity changes, overexploitation, and ocean acidification. The relationship between filter feeders and all these variables is complex and influence species differently at their various life stages. Filter feeders have direct impacts on improving water quality through their filtration abilities. Not only do they filter water, they also act as breakwaters and dissipaters of wave energy along shorelines. This can help decrease shoreline erosion. They act as an important component of living shoreline projects, with the County currently having a stockpile of loose oyster shells ready to be used for restoration projects in the Lagoon. Oyster beds and bars also serve as habitats for numerous organisms. There are currently two areas in the County that allow, or once did allow, for shellfish harvesting, per FDACS. Shellfish harvesting area #70 occurs in southern County starting from Prang Island to Round Island. Clams are present in this area and it has had a restricted classification sinceJune 18, 1997. Shellfish harvesting area #72 occurs in northern County starting at Coconut Point to Paul's Island. Clams are present in this area and it has had a conditional approved status since September 5, 2019. However, this area is closed when two-day cumulative rainfall measured by NOAA exceeds 2.54 inches. When populations were abundant in the Lagoon, having shellfish present in the Lagoon benefited the local economy through harvesting. Currently, the County has oyster populations near the North Relief Canal and Spoil Island IR -43 in the Lagoon, and populations in the mouth of the Saint Sebastian River, a tributary to the Lagoon. Oyster growth also occurs in abundance on mangrove roots or along seawalls in the central and southern parts of the Lagoon. However, these oysters are not usually included in traditional mapping reports because these efforts rely on aerial photography. Mapping of oysters living on mangroves has to be done on-site, which requires more effort and time than aerial mapping. In the shoreline mapping recommendation 96