The Deepwater Horizon (DWH) accident in the northern Gulf of Mexico occurred on April 20, 2010 at a water depth of 1525 meters, and a deep-sea plume was detected within one month. Oil contacted and persisted in parts of the bottom of the deep-sea in the Gulf of Mexico. As part of the response to the accident, monitoring cruises were deployed in fall 2010 to measure potential impacts on the two main soft-bottom benthic invertebrate groups: macrofauna and meiofauna. Sediment was collected using a multicorer so that samples for chemical, physical and biological analyses could be taken simultaneously and analyzed using multivariate methods. The footprint of the oil spill was identified by creating a new variable with principal components analysis where the first factor was indicative of the oil spill impacts and this new variable mapped in a geographic information system to identify the area of the oil spill footprint. The most severe relative reduction of faunal abundance and diversity extended to 3 km from the wellhead in all directions covering an area about 24 km2. Moderate impacts were observed up to 17 km towards the southwest and 8.5 km towards the northeast of the wellhead, covering an area 148 km2. Benthic effects were correlated to total petroleum hydrocarbon, polycyclic aromatic hydrocarbons and barium concentrations, and distance to the wellhead; but not distance to hydrocarbon seeps. Thus, benthic effects are more likely due to the oil spill, and not natural hydrocarbon seepage. Recovery rates in the deep sea are likely to be slow, on the order of decades or longer.
References
[1]
Griffiths SK (2012) Oil release from Macondo Well MC252 following the Deepwater Horizon Accident. Environ Sci Technol 46: 5616–5622.
[2]
NOAA USGS(2010) BP Deepwater Horizon Oil Budget: What Happened to the Oil? www.noaanews.noaa.gov/stories2010/PDFs/O？ilBudget_description_%2083final.pdf.
[3]
Ryerson TB, Camilli R, Kessler JD, Kujawinski EB, Reddy CM, el al (2012) Chemical data quantify Deepwater Horizon hydrocarbon flow rate and environmental distribution. Proc Natl Acad Sci U S A 109: 20246–20253.
[4]
Peterson CH, Anderson SS, Cherr GN, Ambrose RF, Anghera S, et al. (2012) A tale of two spills: novel science and policy implications of an emerging new oil spill model. Bioscience 62: 461–469.
[5]
UAC (Unified Area Command) (2010) Deepwater Horizon MC 252 Response Unified Area Command – Strategic Plan for Sub-Sea and Sub-Surface Oil and Dispersant Detection, Sampling, and Monitoring. November 13, 2010 Final, U.S. Coast Guard and BP Exploration and Production, Inc. New Orleans, LA. USA.
[6]
Neff JM, Rabalais NN, Boesch DF (1987) Offshore oil and gas development activities potentially causing long-term environmental effects, in Long-Term Environmental Effects of Offshore Oil and Gas Development, Boesch DF, Rabalais NN (eds.) Elsevier Applied Science, London, 149–174.
[7]
Kennicutt MCII, Boothe PN, Wade TL, Sweet ST, Rezak R, et al. (1996) Geochemical patterns in sediments near offshore production platforms. Can J Fish Aquat Sci 53: 2554–2566.
[8]
Danovaro R, Gambi C, Anno AD, Corinaldesi C, Fraschetti S, et al. (2008) Exponential decline of deep-sea ecosystem functioning linked to benthic biodiversity loss. Current Biol 18: 1–8.
[9]
Tyler PA, Ed. (2003) Ecosystems of the Deep. Elsevier Science, Amsterdam, Netherlands.
[10]
Hessler RR, Sanders HL (1967) Faunal diversity in the deep sea. Deep-Sea Res 14: 65–78.
[11]
Etter RJ, Rex MA, Chase MC, Quattro JM (1999) A genetic dimension to deep-sea biodiversity. Deep-Sea Res I 46: 1095–1099.
[12]
Grassle JF, Maciolek NJ (1992) Deep-sea species richness: Regional and local diversity estimates from quantitative bottom samples. Am Nat 139: 313–341.
[13]
Rex MA (1981) Community structure in the deep-sea benthos. Ann Rev Ecol System 12: 331–353.
[14]
Haedrich RL, Devine J, Kendal V (2008) Predictors of species richness in the deep-benthic fauna of the northern Gulf of Mexico. Deep-Sea Res II 55: 2650–2656.
[15]
Wei C, Rowe GT, Hubbard GF, Scheltema AH, Wilson GDF, et al. (2010) Bathymetric zonation of deep-sea macrofauna in relation to export of surface phytoplankton production. Mar Ecol Prog Ser 399: 1–14.
[16]
Kennicutt MCII, Green RH, Montagna PA, Roscigno PF (1996) Gulf of Mexico Offshore Operations Experiment (GOOMEX) Phase I: Sublethal responses to contaminant exposure introduction and overview. Can J Fish Aquat Sci 53: 2540–2553.
[17]
Montagna PA, Harper DE Jr (1996) Benthic infaunal long-term response to offshore production platforms in the Gulf of Mexico. Can J Fish Aquat Sci 53: 2567–2588.
[18]
Hill MO (1973) Diversity and evenness: a unifying notation and its consequences. Ecology 54: 427–432.
[19]
Ludwig JA, Reynolds JF (1988) Statistical Ecology. John Wiley and Sons, New York.
[20]
Jenks GF (1967) The Data Model Concept in Statistical Mapping. Internat. Yearbook Cartography 7: 186–190.
[21]
Raffaelli DG, Mason CF (1981) Pollution monitoring with meiofauna, using the ratio of nematodes to copepods. Mar Pollut Bull 12: 158–163.
[22]
Coull BC, Hicks GRF, Wells JBJ (1981) Nematode/Copepod ratios for monitoring pollution: A rebuttal. Mar Pollut Bull 12: 278–281.
[23]
Warwick RM (1981) The nematode/copepod ratio and its use in pollution ecology. Mar Pollut Bull 12: 329–333.
[24]
Marcotte BM, Coull BC (1974) Pollution, diversity and meiobenthic communities in the north Adriatic (Bay of Piran; Yugoslavia). Vie Milieu 24: 281–300.
[25]
Shiells GM, Anderson KJ (1985) Pollution monitoring using the nematode/copepod ratio. A practical application. Mar Pollut Bull 16: 62–68.
[26]
Gee MJ, Warwick RM, Schaanning M, Berge JA, Ambrose WG (1985) Effects of organic enrichment on meiofaunal abundance and community structure in sublittoral soft sediments. J Exp Mar Biol Ecol 91: 247–262.
[27]
Baguley JG, Montagna PA, Hyde LJ, Kalke RD, Rowe GT (2006) Metazoan meiofauna abundance in relation to environmental variables in the northern Gulf of Mexico deep sea. Deep Sea Res I 53: 1344–1362.
[28]
Weisberg RH, Zheng L, Liu Y (2011) Tracking subsurface oil in the aftermath of the Deepwater Horizon well blowout. Geophys Monogr Ser 195: 205–215.
[29]
Camilli R, Reddy CM, Yoerger DR, Van Mooy BAS, Jakuba MV, et al. (2010) Tracking hydrocarbon plume transport and biodegradation at Deepwater Horizon. Science 330: 201–204.
[30]
Kessler JD, Valentine DL, Redmond MC, Du M, Chan EW, et al. (2011) A persistent oxygen anomaly reveals the fate of spilled methane in the deep Gulf of Mexico. Science 331: 312–315.
Valentine DL, Mezi？ I, Ma？e？i？ S, ？rnjari？-？ic N, Ivi？ S, et al. (2012) Dynamic autoinoculation and the microbial ecology of a deep water hydrocarbon irruption. Proc Natl Acad Sci U S A 109: 20286–20291.
[33]
Lu Z, Deng Y, Van Nostrand JD, He Z, Voordeckers J, et al. (2012) Microbial gene functions enriched in the Deepwater Horizon deep-sea oil plume. ISME J 6: 451–460.
[34]
Beazley MJ, Martinez RJ, Rajan S, Powell J, Piceno YM, et al. (2012) Microbial Community Analysis of a Coastal Salt Marsh Affected by the Deepwater Horizon Oil Spill. PLoS ONE 7(7): e41305.
[35]
Bik HM, Halanych KM, Sharma J, Thomas WK (2012) Dramatic Shifts in Benthic Microbial Eukaryote Communities following the Deepwater Horizon Oil Spill. PLoS ONE 7(6): e38550 doi:10.1371/journal.pone.0038550.
Das N, Chandran P (2011) Microbial degradation of petroleum hydrocarbon contaminants: An overview. Biotechnol Res Internat 2011: Article ID 941810, 13 pages, doi:10.4061/2011/941810.
[38]
Beolchini F, Rocchetti L, Regoli F, Dell’Anno A (2010) Bioremediation of marine sediments contaminated by hydrocarbons: Experimental analysis and kinetic modeling. J Hazardous Materials 182: 403–407.
[39]
Boucher G (1985) Long term monitoring of meiofauna densities after the Amoco Cadiz oil spill. Mar Pollut Bull 16: 328–333.
[40]
Dauvin JC (1998) The fine sand Abra alba community of the Bay of Morlaix twenty years after the Amoco Cadiz oil spill. Mar Pollut Bull 36: 669–676.
[41]
Baguley JG, Montagna PA, Hyde LJ, Rowe GT (2008) Metazoan meiofauna biomass, grazing, and weight-dependent respiration in the Northern Gulf of Mexico deep sea. Deep-Sea Res II 55: 2607–2616.
[42]
Rowe GT, Wei C, Nunnally C, Haedrich R, Montagna P, et al. (2008) Comparative biomass structure and estimated carbon flow in food webs in the deep Gulf of Mexico. Deep-Sea Res II 55: 2699–2711.
