Parasites of fishes are a large portion of marine biodiversity, easily outnumbering fish species, but so far have received little attention as bioindicators (biosensors) of anthropogenic pollution in the Gulf of Mexico. Changes to this ecologically diverse community of fish parasites, including those living on the surface of fishes (ectoparasites) and those living within fishes (endoparasites), are known to be associated with marine pollution and indicate negative alterations to the marine food web and also to water quality of coastal and offshore fish habitats. This research will help document the immediate and extended environmental "ripple effects" associated with the Deep Water Horizon Oil Spill in the north-central Gulf of Mexico as well as inform about the use of parasites as bioindicators of oil pollution on a regional scale.
Partnerships with federal (Southeast Fisheries Science Center, NOAA, NMFS), state (Florida Marine Research Institute, Florida Fish and Wildlife Conservation Commission), and university (Auburn University, Middle Tennessee State University, and University of Southern Mississippi) scientists and fisheries biologists have been established for this regional study. The project complements other NSF-RAPID projects that aim to monitor the effects of the Deep Water Horizon Oil Spill in the Gulf of Mexico basin.
A goal of this project was to use parasitological data to test the hypothesis that oil contamination (or other anthropogenic disturbance) leads to a reduction in parasite biodiversity (quantified by parasite component community richness). The recent 2010 oil spill in the Gulf of Mexico represented an unprecedented opportunity to apply our knowledge of the estuarine fauna of Barataria Bay to test the use of parasites as ecosystem indicators. Specific objectives of the work were to (i) complete seasonal collections of Gulf killifish from Barataria Bay (an oiled marsh site), (ii) enumerate parasite component community diversity, (iii) conduct statistical tests to determine changes in abundance and diversity of parasites in Barataria Bay, (iv) publish related findings in peer-reviewed journals, and (v) strengthen collaborations and seek continued funding for monitoring oiled marsh sites. Parasitological necropsies of >600 individual killifish have resulted in an estimated 33 parasite species (7 ecto- & 26 endoparasites) from across our collection sites. Field collections are complete, laboratory processing of samples is nearly complete, and analysis of data from those samples is nearing completion and soon to be submitted for publication. Ultimately, these data and resulting analyses will improve our ability to monitor impacts of the DHOS and hasten a deeper understanding of potential impacts of oil spills in coastal zones.
