Abstract:

The objective of the funded research is to examine the potential effects of the Deep Water Horizon oil spill on the structure of zooplanktonic communities on the Alabama inner shelf, based on data provided by the FOCAL (Fisheries and Oceanography in Coastal Alabama) survey. Zooplankton samples collected between May and August 2004 to 2009 at two offshore stations were analyzed, and compared with samples collected during the same periods in 2010, in order to identify potential variations in the relative composition of zooplankton assemblages due to the oil spill. Analyses of environmental conditions encountered in the area over the study period allowed verifying that conditions in May-August 2010 felt within the range of environmental variability usually encountered in May-August in the region. Observed changes in zooplankton community composition can thus be directly related to the oil spill. However, these changes remained limited to a relatively short time period, with differences being significant in May and June, and a return to the usual community composition as early as July 2010.