The supply of oyster spat (A.K.A. ‘seed oysters’) is crucial for the sustainability and development of the oyster aquaculture industry. While hatcheries worldwide are increasing spat production, wild spat collection remains prevalent in Atlantic Canada. This project explores how environmental conditions influence the timing of larval settlement in the Eastern oyster, a key factor in both wild spat collection and the long-term sustainability of Nova Scotia’s oyster aquaculture industry by providing insights to help growers, managers, and policy makers plan for both current and future aquaculture conditions.
The first component of this research uses a Growing Degree Day (GDD) model framework to quantify how temperature drives larval development. The model was calibrated using existing literature and validated with field observations collected across four estuaries in northern Nova Scotia during the 2022 growing season.
The second component utilizes the GDD approach to evaluate how oyster settlement may shift under changing ocean conditions across three time periods: Past (1991–1995), Present (2021–2025), and Future (2051–2055 under RCP 8.5). The results suggest that warming ocean temperatures may lead to earlier settlement and potential expansion of suitable oyster habitat across Atlantic Canada, which may result in a possible trophic mismatch between larval presence and food availability.
This work was conducted as part of an MSc thesis in Oceanography at Dalhousie University and was co-funded by the Centre for Marine Applied Research (a division of Perennia Food and Agriculture corp.), the MITACS Accelerate program, a Globalink Research Internship award, and the NSERC Discovery Grant of Dr. Ramón Filgueira.
