Date of Award


Degree Type

Masters Thesis

Degree Name

Master of Science (MS)


Ocean Science and Engineering

Committee Chair

Dr. Eric N. Powell

Committee Chair School

Ocean Science and Engineering

Committee Member 2

Dr. Xiaodong Zhang

Committee Member 2 School

Ocean Science and Engineering

Committee Member 3

Dr. Chet F. Rakocinski

Committee Member 3 School

Ocean Science and Engineering


Oyster population maintenance and growth require sufficient larval stocks capable of timely development, growth, and successful metamorphosis, whereby larval performance and settlement potential determines the capacity for a larval cohort to effectively establish into an existing population. Exogenous factors influencing larval performance include temperature, salinity, and particularly food supply. Regarding food, a sufficiently abundant and nutritionally balanced diet composed of protein, lipids, and carbohydrates is critical for successful metamorphosis. The influence of exogenous factors on Crassostrea virginica settlement potential were examined in Delaware Bay and Mississippi Sound by incorporating in situ environmental conditions and food supply metrics into a well-established biochemically-based larval performance model. Additionally, physiological variation in initial egg size, lipid content, and assimilation efficiency was modeled to reflect potential within-cohort phenotypic variability. Extended periods of suppressed salinity routinely impeded larval survival, but under adequate environmental conditions, food quality was the primary control on larval success. Reproductive seasons with favorable exogenous conditions prolonged settlement windows whereas strenuous conditions constrained settlement windows. Evaluating simulated settlement windows against concurrent recruitment observations validated the predictive power of the model and emphasized the importance of food quality on larval performance. To further characterize food assemblages available to oyster larvae in Mississippi Sound, linkages between inherent optical properties to environmental conditions and biochemical food metrics were investigated. Phytoplankton and colored detritus distributions were inferred via measured absorption coefficients but exhibited weak correspondence to biochemical metrics. Optical analyses demonstrated that biochemical food analyses remain superior food supply indicators over chlorophyll and particulate matter measurements.

Available for download on Saturday, May 31, 2025