Abstract:
On August 10, 1993, a major oil spill occurred when approximately 1.2 million liters of Bunker C fuel oil spilled from the fuel tanker Bouchard 155, which had collided with the phosphate freighter Balsa 37 in a shipping channel at the entrance to Tampa Bay, Florida. Wind currents transported the oil to John's Pass and onto several mangrove islands, particularly Eleanor Island. An investigation followed this incident examining changes in the hydrocarbon profile of oil found in the environment. Sediment, oil mass samples and mangrove prop roots were analyzed. Results of this study show that significant levels of polycyclic aromatic hydrocarbons (PAH) remained in all samples after one year. Few studies had been undertaken to determine any short or long term effects of hydrocarbon contamination on benthic communities, which led to this project. The objectives of this study were to collect sediment cores from Eleanor Island in areas common to the original study done in 1993 and a subsequent study in 1996. These cores were to be analyzed for total hydrocarbon concentration and PAH composition. Complimentary cores were to be taken at the same locations and assessed for total benthic community species abundance and diversity. Results are described and comparisons were made to the earlier studies to determine any correlations between hydrocarbon concentrations and community structure.
