Sensitivity analysis of sea scallop (Placopecten magellanicus) larvae trajectories to hydrodynamic model configuration on Georges Bank and adjacent coastal regions

Abstract

AbstractThe previous larval‐trajectory modeling studies on Georges Bank were assessed through process‐oriented Lagrangian‐tracking comparison experiments using the high‐resolution Gulf of Maine/Georges Bank Finite‐Volume Coastal Ocean Model (GOM‐FVCOM). The results indicate that in a strong nonlinear system such as Georges Bank, the passive tracer movement is driven by a fully three‐dimensional Lagrangian flow field that varies in space and time due to large tidal excursion and steep bottom topography. The particle‐tracking methods developed based on the assumption of weak nonlinearity of the flow field are not applicable to Georges Bank. The results of previous larval transport studies driven by circulation fields constructed under the weak‐nonlinearity assumption need to be interpreted with caution. In the present work, the influence of model physical setups on sea scallop larval dispersal and settlement on Georges Bank and adjacent shelf regions is examined. Distinct differences in the spatial distribution of the passive larvae predicted by the model under various physical conditions suggest that a fully nonlinear model driven by realistic spatially and temporally varying forcing should be employed for Lagrangian‐based studies of fishery population dynamics on Georges Bank.