Researchers from the University of South Florida found oil in plankton in the northern Gulf. Plankton are tiny organisms which many larger species such as fish consume in order to stay alive. If plankton numbers plunge, there could be a similar impact on all the species which depend on them. One of the scientists from the University, David Hollander said, “The idea that this could have an impact on the food web and on the biological system is certainly a reality.”
Plankton contaminated with oil will also be ingested by fish, that will in turn contain trace amounts of oil. Toxins are thought to be passed on from smaller to larger fish that eat them. Eventually this process of bioaccumulation can result in humans consuming the toxins. The FDA declared seafood from the Gulf safe to eat, but even some Louisiana fisherman said they had doubts about that being true at this stage.
Carol M. Browner, the White House climate and energy czar said, “more than three-quarters of the oil is gone. The vast majority of the oil is gone.” David Hollander has said actually the reverse is true, that about 70-75 percent of the oil has not been dispersed. His estimate was that only 25-30 percent of the oil had been skimmed, burned, or had evaporated. Another USF researcher, John Paul commented, “The dispersant is moving the oil down out of the surface and into the deeper waters, where it can affect phytoplankton and other marine life.”
The USF research is considered preliminary, but it did find toxicity in deep water samples at 275 meters and 50 meters. Those were the depths with the largest toxic response. For one of the underwater tests, 39 percent of the samples showed toxicity, though this number needs to be confirmed by a statistical analysis. Oil was also found in DeSoto Canyon which is a deep underwater area thought to be an important spawning area for Gulf fish, about forty miles from Panama City, Florida.
Image Credit: Plankton, Public Domain