<p>The eastern oyster is an important bivalve species in coastal Louisiana due to its role as an ecosystem engineer and its high commercial value. Given the importance of larval growth, mortality, and transport in shaping oyster population dynamics, we developed a coupled hydrodynamic-larval transport model and simulated years 2014 to 2018. The model was used to examine the spatial pattern of oyster larval dispersal during spring spawning season and to explore the environmental drivers of larval growth in Barataria Estuary, Louisiana. Low salinity was the primary factor contributing to reduced larval growth and increased mortality, driven by both low mean conditions and prolonged exposure to low-salinity environments (&lt; 7.5 PSU) associated with high salinity variability, whereas temperature did not differ substantially between dead and settled larvae. Reduced larval growth and settlement failure heavily influenced estuarine subregion connectivity. Specifically, only one subregion in the southwestern region of the estuary was not impacted by low salinity, making that subregion potentially self-sustaining. In contrast, settlement in other subregions relied on larval inputs from adjacent areas. Although low salinity due to increased river discharge was adverse to larval settlement in the model, other factors such as turbidity, food supply, and the joint effects of multiple stressors would be important in nature. Including these factors in future model development will contribute to more accurate simulations of oyster larval growth, dispersal, and settlement across the oyster grounds under changing estuarine environments. Given the strong spatial heterogeneity in oyster larval dynamics, larval transport models offer critical insights for oyster restoration and management strategies. Comprehensive field observations with adequate spatiotemporal resolutions are essential for future model development and performance evaluation.</p>