Students Research Presentations: Modeling the effect of environmental factors on oyster growth across diverse habitats in the Chesapeake Bay

Year:

2022

Source:

Ocean Sciences Meeting, Virtual

Abstract:

The eastern oyster (Crassostrea virginica) is an ecologically and commercially important shellfish species in the Chesapeake Bay and estuaries along the Atlantic and Gulf coasts. Restoration projects aim to revive this keystone organisms’ ability to filter the water column, create habitat, and support commercial harvest, while at the same time, aquaculture is expanding. Given the need to understand oyster growth potential in estuarine habitats with diverse and dynamic environmental conditions (e.g., temperature, food availability), numerical models offer a tool to predict oyster growth and identify ideal locations for restoration and aquaculture. We refined and advanced an existing oyster growth model to analyze the combined and isolated effects of salinity, chlorophyll-a concentrations (proxy for food availability), temperature and carbonate saturation state on oyster growth to determine the regions better suited for restoration projects and aquaculture operations. Applications of the model under observed conditions over three-year simulations at 179 monitoring stations in the Chesapeake Bay showed greatest growth in shell length and tissue weight in the Maryland Coastal Bays, northern mesohaline Bay and in regions of the James and York Rivers, where food was abundant and salinity was not growth-limiting. At approximately 70% of the stations, salinity was too low to adequately support net oyster growth, possibly also indicating low calcium carbonate saturation state in the water column. The addition of acidification-induced losses in the net energy balance led to reductions in growth at a subset of the stations we analyzed. These results provide a framework to evaluate growth potential over space in response to multiple stressors under both contemporary and future conditions. Future work will include quantifying the effect of food quality (not simply quantity) on oyster growth and considering growth under future climates.

 

Mentors:

Jeremy Testa Ph.D.

Students:

Melissa Solis, Old Dominion University