字幕表 動画を再生する 英語字幕をプリント The next oil spill won't be a matter of if — but when. Deepwater Horizon may have happened years ago, but significant research is still being conducted to learn as much as possible from the biggest oil disaster in recent United States history, and to find new, less toxic ways to reverse future oil spill damage. During Deepwater Horizon I believe there were 15,000 actual phone calls into the command post suggesting different ways of cleaning up and doing things. If we're doing the same thing every different spill, we're not doing the best we can. Michael Ziccardi spent five months in Louisiana during Deepwater Horizon responding to the disaster. It's his job to think of every aspect of oil spill response. Recently, he has been tracking the behavior of affected marine birds after they have been cleaned by the Oiled Wildlife Care Network, a world-wide model for oil spill preparedness and response. Just by going to the Oiled Wildlife Care Network website we can actually see real time where these animals are at. I honestly think that every oil spill needs to be a learning opportunity. During the Deepwater Horizon oil spill, they did a lot of what are called alternative response techniques. They burned the oil off the surface of the water, but they also used a larger volume of chemical dispersants. Nearly seven million liters of dispersants known as Corexit 9500 and 9527 were used. The concept is it's a surfactant, or a detergent, that goes on top of the oil and breaks it up into very small molecules, driving it into the water column itself. The idea with that not only is it less risk to animals that might be on the surface of the water, but by sending it into the water column it's actually allowing bacteria to break down the oil. Dispersants work similarly to dish soap. Surfactants are long molecules that are water-seeking on one end, or hydrophilic, and oil-seeking, or oleophilic, on the other end. When the surfactant is in turbulent, moving water, it reaches across the oil-water boundary and lowers the tension between water and oil — allowing it to break apart. This was the first time dispersants had ever been used at such an enormous scale. Mike's research centers on how Corexit may affect wildlife — specifically, marine birds and their complex feather structure, which is responsible for keeping them warm. So the feather structure of birds is fascinating. It's a combination of barbs and barbules and hooklets. Think of a piece of Velcro. The feathers basically make that Velcro. When oil affects a bird, there's an artificial separation in that Velcro so it can't stick together. So what ends up happening, is water can seep through the feathers and down to the skin. What we found was something we did not expect at all. At high concentrations, they lost their waterproofing almost immediately. But that waterproofing actually resolved itself within a matter of a day. So it seems like it was a temporary loss and just by swimming in water, or over time they could actually lose that impact. It could be that if dispersant application occurs, you can throw out a raft that animals can haul out on to get themselves warm. They don't need to be captured, they don't need to be brought into rehabilitation where they're going to be there two or three weeks. It's just that temporary fix. Animals could survive it, as long as they're not in the oil as far as the dispersant application. Although the birds' waterproofing seems to recover, Corexit is still very controversial. And Mike and his team — as well scientists around the country — are still investigating the impacts of Corexit's toxicity. Mike hopes this information will shape future decision-making during oil spill response efforts, and encourage alternative approaches that could be less costly and less intrusive to wildlife. I think for the foreseeable future oil spills will always be there. I believe that we have a moral obligation to try to repair the damage and to try to reduce the impacts on the wildlife. It is truly the only thing I've ever wanted to do, is to try to help animals in crises, especially in crises that humans cause.