HEAVY METAL POLLUTION, TEST MUTATIONS, AND FORAMINIFERA ASSEMBLAGE STRESS INDICES ON SAN SALVADOR ISLAND, THE BAHAMAS

Larger benthic foraminifera are a near-ubiquitous group in shallow marine carbonate settings that can be used as an indicator for anthropogenic impacts on local-scale communities. In modern assemblages, high frequencies of test mutation in benthic foraminifera have shown a correlation with local heavy metal pollution. However, few investigations have also attempted to correlate these settings with overall community health. Here, we examine the correlations between heavy metal pollution, frequency of test mutation, and overall benthic community health in San Salvador Island, using paleoecological indices of dominance, evenness, and diversity. We examine 6 sites around the Island with varying potentials for pollution. At each site, Thalassia seagrass, surface sediment, and seawater samples were collected along 30m transects. We use these samples to examine the live assemblage, death assemblage, and heavy metal pollution profile. The frequency of test mutations was counted in all samples. Preliminary results show that, while mutations are present at all sites, at least one potentially polluted site shows elevated mutation rates in both live and dead assemblages. It was also the only site to present deformed tests in the live assemblage. Although these results are preliminary, demonstrating a correlation between sites of local metal pollution, test mutation, and community makeup would allow us to develop test mutation frequency as a valuable and practical way of identifying sites with deleterious anthropogenic impacts, and which are in need of environmental remediation.