Eastern oysters (Crassostrea virginica) are highly valued for the ecosystem services they provide. This is largely due to their filter feeding activity. However, the ability of oyster restoration to improve water quality remains ambiguous because natural variation in biotic and abiotic conditions affects oysters’ filter feeding activity. Previous studies on the filtration services of oysters have examined physiological responses under laboratory conditions with monoculture diets and single parameter variation on day to hour-long in situ settings with coarse temporal scales. Yet, little is known about how their filtration rates vary over weeks in relation to variations in prey and environmental conditions. Studies that closely track direct effects of environmental changes are labor intensive and time consuming, leading to large data gaps.
This study leverages recent advances in aquatic observing, such as real-time flow-through oyster monitoring coupled with a newly implemented phytoplankton observatory on the Choptank River (Cambridge, MD). This system is able to track long-term feeding and metabolic responses of the Eastern oyster in response to subtle variation in environmental quality. The phytoplankton observing system consists of an imaging flow cytobot, fast repetition rate fluorometer, and CTD to determine algal community composition, health, and water conditions. Feeding and respiration is measured under ex situ, flow-through conditions and logged in real-time using sets of fluorometers and respirometers among replicate oysters over week-long experiments. Oyster feeding and respiration responses to prevailing biotic and abiotic conditions are estimated from signal differences among sensors during post processing. This coupled monitoring system enables a deeper understanding of how algal community and environmental variability directly influence oyster physiology. Additionally, data produced by this system can inform models of the potential variation of oyster filter activity under fluctuations of water quality as well as inform farm placement decisions to provide maximum oyster feeding potential.