Benthic taxa as potential indicators of a deep-sea oil spill

The effect of the Deepwater Horizon oil spill on benthic macrofauna in the deep-sea Gulf of Mexico was measured in September-October 2010. Macrofauna community diversity and abundance were lowest closest to the wellhead and increased with distance from the wellhead up to 10 km. The macrofauna loss was primarily in surface sediments, which could be due to the deposition of oil and other toxic chemicals. Crustacean taxa appeared to be sensitive to the deep-sea blowout. Polychaete taxa varied in their sensitivity, but Dorvilleidae which is often associated with organic enrichment, was responsible for the largest amount of dissimilarity between stations close and far from the wellhead. Several other taxa were classified as sensitive or tolerant to the deep-sea blowout by comparing their distributions among impacted and non-impacted zones. The macrobenthic communities in the deep Gulf of Mexico exhibit a toxic response to the blowout on the Deepwater Horizon well, and this is correlated with barium and petroleum hydrocarbons.