Objectives

The goals of this program are motivated by the four research themes of the Cooperative Institute-ecosystem management, geospatial data integration, regional climate effects, and coastal hazards. Those goals include (1) quantifying the onshore and offshore transport mechanisms of the BBR, (2) documenting the basic regional physical oceanography, and (3) clarifying key aspects of the ecosystem that contribute to reef fish productivity. All three goals will be integrated within an overarching BBR modeling framework. The observations, experiments, and modeling foci are directed at ecosystem-based management, coastal hazards, and the impacts of climate variability.

The objective of the transport component is to clarify the basic onshore-offshore transport mechanisms of the BBR. This requires measuring--often for the first time--the detailed structure of BBR currents, key parameters of the wave state, local meteorological forcing, and the BBR temperature, salinity, and tracer fields. It also requires assessing seasonal changes in dissolved organic carbon (DOC) and nitrogen (DON) in the shallow sandy shelf of the northern Gulf of Mexico--key components in coastal nutrient cycles and food webs--and their response to local current and wave regimes.

The objectives of the ecosystems research are to examine the role of primary productivity in sustaining the regional ecosystems and the geospatial and trophic interactions that support productivity in economically important reef fish, using gag as a model species. Relative to the latter, we focus on (1) the effect of climate variability on the growth rate and diet of early juvenile gag in seagrass bed nursery grounds, and (2) trophic linkages that occur between seagrass-bed-derived forage species and offshore production of gag in the shelf-edge environment. We also are investigating (3) the geospatial linkage between juvenile gag primary nursery habitat (seagrass meadows) and secondary nursery habitat (shallow water reefs) as staging areas for recruitment to adult populations offshore, consistent with an ecosystem-based management approach for reef fish species. The modeling component provides broader views of the regional dynamics and incorporates the observations within a single dynamically coherent picture that relates physical dynamics to biological productivity.