The Impact of Nutrient Pollution on Crassostrea virginica populations in the Chesapeake Bay Watershed between the Years 2000 and 2019

The Chesapeake Bay, one of the largest watersheds in the United States, has experienced significant ecological stress due to agricultural fertilizer runoff. Between 2000 and 2019, populations of Crassostrea virginica (Eastern Oyster) declined as a result of eutrophication, reduced shell integrity, and increased prevalence of parasitic pathogens. This study evaluates the relationship between agricultural fertilizer inputs and oyster population health by analyzing water quality data published by the Maryland Department of the Environment in its 2019 Executive Summary and DataHub. Parameters examined include water salinity, pH, dissolved oxygen, and Dermocystidium marinum disease prevalence over the 2000–2019 period. Statistical analysis revealed a direct correlation between elevated salinity and D. marinum prevalence, as well as between D. marinum infections and oyster mortality rates. Findings indicate that agricultural runoff plays a substantial role in compromising the resilience of C. virginica populations, underscoring the ecological consequences of nutrient loading within the Chesapeake Bay watershed.