Understanding Molecular, Energetic and Physiological Responses of Crassostrea virginica to Aerial Desiccation Regimes
2020 - 2021
Horn Point Laboratory, University of Maryland Center for Environmental Science
Strategic focus area:
Sustainable fisheries and aquaculture
Shellfish aquaculture represents a growing industry with strong potential for global expansion. However, biofouling poses a considerable concern to operations, with conservative estimates indicating farmers spend 5-10% of total costs on biofouling removal. Bioexcavators, such as mudworms, are especially problematic as they affect the condition of the oyster, and also leave behind an unsightly mud blister, which is offputting to the half shell industry which prizes pristine oyster shells. Desiccation, or aerial exposure of oysters and cages, has demonstrated marked success in mitigating biofouling, including bioexcavators, but has also been associated with a growth penalty in some desiccated oysters. Prior research has indicated that this is due in part to time spent out of the water and in part to oyster shells chipping as cages were flipped, but new research indicates that this may not be the only driver of the growth penalty. In this proposal, we seek to employ lab techniques to understand this growth penalty with a greater degree of resolution. Using oysters that undergo four desiccation intervals (0, 4, 8 and 24 hours weekly) on a custom-built desiccation hoist system, we seek to examine the energetic and protein responses of cells to these treatments, and to correlate responses with gametogenic stage and growth. Desiccation is known to be stressful to oysters, but information is lacking on oyster responses to desiccation at such fine scale temporal resolution. Such information will provide insight into the drivers of this observed growth penalty. Lacking such information leaves shellfish researchers assuming the growth penalty is a given, but equipped with laboratory based analytical information, researchers and oyster aquaculturists can work together to identify strategies to mitigate this growth penalty. Such information can enhance the burgeoning shellfish industry by informing farm management practices that will aid shellfish businesses.