Physical Connectivity Between Mesophotic Areas in the Northern Gulf of Mexico

Abstract

Understanding connectivity patterns is crucial for marine planning, particularly in the design of marine protected areas or restoration plans. In this study, we assess the potential physical connectivity between mesophotic areas in the northern Gulf of Mexico and investigate the dynamical features influencing such connectivity using a physical modeling approach. We use the Coastal and Regional Ocean COmmunity model in conjunction with a particle transport Lagrangian tool to evaluate the general pathways of material transport among mesophotic areas, focusing on the Flower Garden Banks National Marine Sanctuary and the Pinnacles Trend over 2 years. Additionally, we conduct a sensitivity analysis to identify the minimum necessary model configuration for capturing the impact of kilometer-scale circulation on connectivity metrics. Our results reveal year-round low connectivity potential between mesophotic areas with high seasonal heterogeneity in transport direction and dispersal distances due to the high variability of the currents fields. In the study areas, material dispersion appears to be primarily driven by the extension of shelf currents and by submesoscale circulations (SCs). Sensitivity analysis suggests that high-resolution velocity fields with horizontal grid spacing capable of resolving SCs and temporal resolution of 6 hr or less are required to accurately capture the impact of small-scale circulations on connectivity, especially in summer, when currents are weak and submesoscale fronts are essential to establish dispersion patterns.