Project Director: Deborah Gochfeld

Funding Organization: Mississippi Based RESTORE Act Center of Excellence (MBRACE)

Funding Cycles: MBRACE 2

Description: This project integrates field, laboratory, and policy research on the impacts of low salinity, pH, dissolved oxygen, and harmful algal blooms on the early life stages of oysters in order to inform sustainable oyster reef restoration in Mississippi coastal waters. Oyster reef conservation and restoration in the Mississippi Sound requires an understanding of where oysters can survive and thrive under present conditions. This is particularly important for the early life history stages of oysters, which are generally more sensitive to environmental stressors. Further, stressors rarely occur in isolation, and exposure to multiple simultaneous stressors has even greater effects than exposure to single stressors. For example, the sensitivity of oyster larvae to toxins is enhanced under elevated temperature or reduced salinity. To investigate these issues, the project has several components. First, we are collaborating with the MBRACE Core Research Program to collect temporally and spatially explicit data on levels of abiotic and biotic stressors at current, former, and potential oyster reef sites across the Mississippi Sound. Second, we are exposing oyster larvae and juvenile (“seed”) oysters in laboratory bioassays to a range of water quality conditions independently (Year 1) and in combination (Year 2) to assess the effects of single and multiple stressors on development, growth, and survival of oyster early life history stages. Third, we are out-planting seed oysters in the Core Research Program sensor platforms at oyster gardening, restoration, and aquaculture sites across the Mississippi Sound to evaluate in situ growth and survival after early life stage exposures to stressors. Lastly, we are analyzing the legal and policy framework governing oyster harvesting and oyster reef restoration in Mississippi and will translate our findings into a policy brief that will summarize the implications of our research results for oyster reef management. Collectively, our work will provide recommendations for management options or policy reform to improve the sustainability of oyster populations in Mississippi. The project also includes partnerships with a high school and The Nature Conservancy located on the Mississippi Gulf Coast, who are involved in our in situ experiments and outreach activities.