Temporal patterns of Deepwater Horizon impacts on the benthic infauna of the northern Gulf of Mexico continental slope

RESEARCH ARTICLE Temporal patterns of Deepwater Horizon impacts on the benthic infauna of the northern Gulf of Mexico continental slope Michael G. Reuscher1*, Jeffrey G. Baguley2, Nathan Conrad-Forrest2, Cynthia Cooksey3, Jeffrey L. Hyland4, Christopher Lewis5, Paul A. Montagna1, Robert W. Ricker6, Melissa Rohal1, Travis Washburn1 a1111111111 a1111111111 a1111111111 a1111111111 a1111111111 1 Harte Research Institute for Gulf of Mexico Studies, Texas A&M University-Corpus Christi, Corpus Christi, Texas, United States of America, 2 Department of Biology, University of Nevada-Reno, Reno, Nevada, United States of America, 3 National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Charleston, South Carolina, United States of America, 4 National Centers for Coastal Ocean Science, National Oceanic and Atmospheric Administration, Charleston, South Carolina, United States of America, 5 Industrial Economics, Incorporated, Cambridge, Massachusetts, United States of America, 6 Office of Response and Restoration, Assessment and Restoration Division, National Oceanic and Atmospheric Administration, Santa Rosa, California, United States of America * OPEN ACCESS Citation: Reuscher MG, Baguley JG, ConradForrest N, Cooksey C, Hyland JL, Lewis C, et al. (2017) Temporal patterns of Deepwater Horizon impacts on the benthic infauna of the northern Gulf of Mexico continental slope. PLoS ONE 12(6): e0179923. https://doi.org/10.1371/journal. pone.0179923 Editor: Stefan J. Green, University of Illinois at Chicago, UNITED STATES Received: February 28, 2017 Accepted: June 6, 2017 Published: June 22, 2017 Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication. Data Availability Statement: Data are publicly available through the Gulf of Mexico Research Initiative Information & Data Cooperative (GRIIDC) at https://data.gulfresearchinitiative.org (doi: [10. 7266/N7GQ6VSX, 10.7266/N7BZ643F, 10.7266/ N7765CDG]). Funding: Sample collection on R/V Gyre and R/V Ocean Veritas during the Deepwater Horizon (DWH) oil spill response phase was funded by British Petroleum (BP) and the National Oceanic Abstract The Deepwater Horizon oil spill occurred in spring and summer 2010 in the northern Gulf of Mexico. Research cruises in 2010 (approximately 2–3 months after the well had been capped), 2011, and 2014 were conducted to determine the initial and subsequent effects of the oil spill on deep-sea soft-bottom infauna. A total of 34 stations were sampled from two zones: 20 stations in the “impact” zone versus 14 stations in the “non-impact” zone. Chemical contaminants were significantly different between the two zones. Polycyclic aromatic hydrocarbons averaged 218 ppb in the impact zone compared to 14 ppb in the non-impact zone. Total petroleum hydrocarbons averaged 1166 ppm in the impact zone compared to 102 ppm in the non-impact zone. While there was no difference between zones for meiofauna and macrofauna abundance, community diversity was significantly lower in the impact zone. Meiofauna taxa richness over the three sampling periods averaged 8 taxa/sample in the impact zone, compared to 10 taxa/sample in the non-impact zone; and macrofauna richness averaged 25 taxa/sample in the impact zone compared to 30 taxa/sample in the nonimpact zone. Oil originating from the Deepwater Horizon oil spill reached the seafloor and had a persistent negative impact on diversity of soft-bottom, deep-sea benthic communities. While there are signs of recovery for some benthic community variables, full recovery has not yet occurred four years after the spill. Introduction The deep sea is considered a generally stable environment where living organisms are less frequently challenged with steep changes in physical and chemical conditions compared to their PLOS ONE | https://doi.org/10.1371/journal.pone.0179923 June 22, 2017 1 / 17 Temporal patterns of Deepwater Horizon impacts and Atmospheric Administration (NOAA). Sample collection on the 2011M/V Sarah Bordelon and 2014 M/V Irish cruises, follow-up sample processing and data analysis, and production of this paper were funded in part under contract DG133C06NC1729 from NOAA’s Office of Response and Restoration (ORR) via subcontract 1050-TAMUCC and 1050-UNR from Industrial Economics (IE), and through an internal transfer of funds from NOAA’s Office of Response and Restoration (OR&R) to NOAA’s National Centers for Coastal Ocean Science (NCCOS), as part of the DWH Natural Resource Damage Assessment. The views expressed herein are those of the authors and do not necessarily reflect the views of NOAA or any of its personnel. The study design and scope of work for the present deep-water/soft-bottom benthic study was approved jointly by representatives of the DWH NRDA Trustees and BP; neither party had a role in the corresponding sample processing, data analysis, decision to publish, or preparation of the manuscript. Christopher Lewis is employed by Industrial Economics, Incorporated. Industrial Economics, Incorporated provided support in the form of salary for author CL, but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific role of this authors is articulated in the ‘author contributions’ section. Competing interests: The authors have the following interests: Ships for sample collection was funded by British Petroleum (www.bp.com). Christopher Lewis is employed by Industrial Economics, Incorporated. The study design and scope of work for the present deep-water/softbottom benthic study was approved jointly by representatives of the DWH NRDA Trustees and BP. There are no patents, products in development or marketed products to declare. This does not alter the authors’ adherence to all the PLOS ONE policies on sharing data and materials, as detailed online in the guide for authors. coastal counterparts. Nevertheless, many different forms of natural disturbances that may disrupt the apparent ecosystem equilibrium of the deep sea have been observed, including benthic storms [1], mud slides [2], whale falls [3], and mass deposition of phytodetritus [4], among others. Subsequent recolonization and faunal successions of the affected areas are very slow in the deep sea [5]. The patchy nature of the deep-sea benthos may be a direct consequence of these disturbances because every “patch” may represent a community in a different faunal successional stage [6]. Seasonal and interannual variation of particulate organic matter (POM) transport to the deep sea through benthic-pelagic coupling is well documented [4,7]. Detritus derived from phytoplankton blooms may sink rapidly to the seafloor [8] and trigger a response by the benthic communities wit (...truncated)