I once helped draw blood from a wild falcon, its lithe wings gently lashed, its head covered to calm it. Biologists have been taking such tests for more than thirty years, tracking toxins in the predatory birds as they make landfall after spending months in Central and South America, where chemicals such as DDT and PCB aren’t banned like they are in the United States, since the 1970s. A month earlier I’d heard Charles Henny, a U.S. Geological Survey wildlife biologist with a focus on toxicology, say that by 2004 there was almost no detectable DDT in these falcons, whose populations had crashed due to DDT but then recovered. But there was something new on his radar. “There’s other stuff that’s replaced it,” he said. “My concern right now is the flame retardants.”
