Meeting Abstract

P1-23   -   Environmental Factors Contributing to Perkinsus marinus Infection in Crassostrea virginica at natural reefs in Estero Bay, Florida Browning, S*; May, MA; Florida Gulf Coast University, Fort Myers, FL; Florida Gulf Coast University, Fort Myers, FL slbrowning6524@eagle.fgcu.edu

Eastern oysters (Crassostrea virginica) play a crucial role in the health of aquatic ecosystems in southwest Florida by improving water quality via filter feeding, thereby helping to remove excess nutrients and heavy metals from the water column. Oyster reefs in Southwest Florida are in decline, in part due to high infection loads by the parasitic protist, Perkinsus marinus, which causes a tissue-wasting disease known as dermo. There are a variety of factors that play a role in Perkinsus infection, including water quality and the overall health of adult C. virginica. While studies have shown a strong relationship between salinity and infection ranking, as well as condition index and the sex of oysters from laboratory and aquaculture-based studies, few have evaluated infection in intertidal reefs or the drivers of infection across small spatial scales. As part of biweekly monitoring of oyster reefs in Estero Bay, we sampled oysters from 5 reefs in Estero Bay that vary in overall reef health and hydrodynamics throughout 2021. At each site, water quality parameters were measured, water samples were taken for nutrient and chlorophyll content, and oysters were collected to determine condition index and Perkinsus infection using Ray’s Fluid Thioglycolate media. During the summer months, we also recorded oyster settlement, in situ juvenile growth, and sediment flux. Preliminary data suggest that the driving factors of Perkinsus infection are more complex than previous studies have reported and are likely heavily impacted by multiple environmental stressors experienced by the oysters. Overall, this research will provide additional insight into drivers of oyster health in natural settings and help inform restoration efforts in Southwest, Florida.