Oceans and Ecosystems

Over the past 10 years, the AOML Physical Oceanography Division (PhOD) and the National Marine Fisheries Service (NMFS) / Southeast Fisheries Science Center (SEFSC) / Early Life History (ELH) laboratory have worked in collaboration to study regional biophysical linkages at several locations within the Caribbean Sea and Gulf of Mexico (Intra-Americas Sea).

PhOD - SEFSC collaborative field programs typically include interdisciplinary sampling techniques conducted during shipboard surveys of project study areas. Biological sampling, utilizing both profiling and surface nets, is performed simultaneously with standard physical sampling methods such as CTD/LADCP (Conductivity-Temperature-Depth/Lowered Acoustic Doppler Current Profiler) casts and hull-mounted water velocity measurements. This approach provides greater insight to scientific and management questions regarding larval recruitment pathways than biological sampling alone. Deployments of moored instrumentation and Lagrangian surface drifters have also been utilized to augment the physical data sets associated with these endeavors.

Regional Biophysical Connectivity Collaborations around the Intra-Americas Sea:

Gulf of Mexico and Western Caribbean: • Mesoamerican System Transport & Ecology Research The MASTER program is designed to improve our understanding of grouper and snapper larval dispersal and recruitment connections within and between the Mesoamerican reef system, the Dry Tortugas, and the Florida Keys reef tract. In studying these linkages, scientists aim to determine what component of recruitment is due to broad, regional biophysical connections versus self-recruitment within the Mesoamerican reef system. Figure 1. (at right) Satellite-tracked Lagrangian surface drifter trajectories produced from buoys deployed during the second MASTER cruise in January 2007 (click on image to enlarge view).

Northeastern Caribbean: • USVI Larval Reef Fish Distribution and Supply Study • Vieques Sound and Virgin Passage Transport Study Transport of larval reef fish across the Puerto Rico and US Virgin Islands (PR/USVI) shelf and through passages between the islands is poorly understood. The natural dispersal of these newly spawned larvae is affected by many factors, including bottom regime, island/shelf/bank geometry, tides, small-scale retention mechanisms, mesoscale gyres, and larger-scale mean fields such as wind-driven transport. These processes may carry larvae off the shelf to unsuitable habitat, or relocate them to nearshore areas where settlement is favorable. These programs are designed to help scientists and resource managers gain a better understanding of how managed and non-managed areas of the US Caribbean and surrounding region (British Virgin Islands and Leeward Islands) are linked via the highly variable flow across this region, and to determine what economically important larval reef fish dispersal and recruitment pathways exist as a result. An improved understanding of region-wide coral reef ecosystem connectivity is required for the development of effective long-term adaptive fisheries management strategies in the US Caribbean. Figure 2. Ocean surface current velocities are shown, as observed during the third USVI Larval Reef Fish Distribution and Supply Study research cruise in 2009. Data were collected using a 150 kHz vessel-mounted acoustic Doppler current profiler (ADCP). The velocity vectors shown reveal the highly variable nature of surface currents in the region (click on image to enlarge view).