ASSESSING DEEPWATER HORIZON OIL AND DISPERSANT CONTAMINATION IN BLUE CRAB, CALLINECTES SAPIDUS, MEGALOPAE

The Deepwater Horizon oil spill occurred during the peak spawning season of the blue crab, Callinectes sapidus, an economically and ecologically valuable species to Gulf of Mexico. Contamination of larvae by crude oil and dispersants associated with the spill is likely given the life history of blue crabs. Egg-bearing females leave estuaries to spawn 10-100s of miles offshore. Once spawned, these eggs quickly hatch into planktotrophic larvae which undergo 7 molts over ~40 days as they drift in surface currents. After this time, they will re-enter estuaries as post-larval megalopae if currents are favorable. To estimate the spatial and temporal extent of oil and dispersant (Corexit EC9500A and Corexit EC9527A) contamination of blue crab megalopae recruiting back to estuaries, we deployed 4 passive collectors at 9 coastal sites ranging from Galveston, FL to Apalachicola, FL. Collectors were sampled 5 days a week from May 18^th to October 29^th 2010. Spatio-temporal patterns of megalopae recruitment will be discussed. We will also report the spatio-temporal distribution of abnormal orange droplets found inside the carapaces of some megalopae, as well as results of chemical analyses undertaken to test for the presence of oil and dispersant in these droplets (GC-MS, LC-ESI-MS, UV-Visible and Flourescence spectroscopy).