Monitoring oil spill bioremediation using marsh foraminifera as indicators

A controlled experiment was conducted in June 2000 to identify the environmental impacts of weathered crude oil on an Atlantic coastal salt marsh to help evaluate in situ biological remediation techniques for restoring the environment. Foraminifera, marsh microfossils known to be sensitive to a range of environmental stress factors, were used to monitor the effects of the residual oil and the experimental treatments. Results show that the foraminifera responded quickly to the oil and that the oil had a statistically significant, negative impact, as demonstrated by a dramatic increase in deformities in the tests of Miliammina fusca, compared to specimens from the non-oiled control plots. The results clearly show that foraminifera can be excellent indicators of oil pollution using only the percent of deformed tests. The advantages that foraminifera provide are the ease of sampling, processing and examination, with the added benefit that these organisms leave a fossil record.