A simulation analysis of the plankton fate of the Deepwater Horizon oil spills, Northern Gulf of Mexico, 2010-2011

A two-dimensional (2-D) ecosystem model, set within the De Soto Canyon ecotone of the Northern Gulf of Mexico (NGOM) and driven by 3-D flow fields from coupled circulation models, explores the daily food web and sedimentary consequences of oil-, nutrient-, and overfishing-induced transitions of dominant particle transports to the sea floor: from changing vectors of copepod fecal pellets to those of marine snow over the annual period of 2010-2011. Recent spilled petrochemicals are found to minimally impact already decimated zooplankton populations on the West Florida shelf (WFS). They facilitate instead formation of marine snow macroaggregates. The model results here replicate concurrent time series of: 1) annual sediment accumulations, measured at the sea floor; 2) bimonthly onshore nutrient supplies, due to upwelling, forced remotely by the Loop Current; and 3) near-surface weekly phytoplankton changes, seen by satellite.