Effect of Corexit on the Oxygen Consumption of Early Life Stage Mahi-Mahi

Nearly 7 million liters of chemical dispersant were applied as part of the response to the Deepwater Horizon oil spill. While previous work has shown that the dispersant, Corexit 9500, is not toxic to early life stage mahi-mahi in terms of acute (96 h) mortality at environmentally relevant concentrations, sublethal impacts of acute exposures have yet to be examined. To this end, a microplate respirometer was employed to examine mahi-mahi embryos and larvae exposed to two different concentrations of dispersant for 24 h to investigate potential impacts on metabolic rate. Potential increases in metabolic rate would likely induce a more rapid depletion of yolk, reflecting a diversion of energy from growth to detoxification. As the yolk is the sole source of nutrition prior to mouth opening and first feeding by the larvae, such potential effects of dispersant thus could have important downstream implications for survival that would be missed by employing standard 96 h bioassay approaches. This dataset provides the metabolic rate measurements from these experiments.