Understanding the interconnectedness of inshore and offshore fishes within the southeast Florida shelf is vital for assessing tend predicting the effect of the British Petroleum Deepwater Horizon (DWH) event effluent. The narrow continental shelf allows for rapid transport of offshore contaminants into inshore environments from the likely transport mechanism of DWH oil and dispersant (OD) contaminants from the northeastern Gulf of Mexico through the Loop and Florida Currents. We will conduct fisheries independent sampling at three week intervals across the width of the southeast Florida shelf to establish a baseline understanding of the coastal pelagic ecosystem in order to detect ecosystem shifts, which can then be used in turn to assess changes in community structure from anthropogenic sources. Stomach contents analysis will be used to determine predator-prey interactions, with additional analyses of nitrogen stable isotope ratios to determine trophic level and carbon stable isotope ratios to trace carbon sources in the diet of these coastal pelagic fishes. The samples will also be used to trace exposure and effects fo exposure to polycyclic aromatic hydrocarbons (PAHs). The potential toxicological effects for the DWH event on coastal pelagic fishes in the Florida Straits will be assessed by conduction laboratory-based assays for the chytochrome P4501A1, biliary fluorescent aromatic compounds, and PAH-DNA adduct biomarkers. These combined trophic and ecotoxicity studies will provide important information for assessing policy options for the coastal pelagic fisheries resources of the Florida Straits.