"As oil and gas companies press to tap new deposits in remote places, scientists are trying to gauge and limit the ecological impact of pipes and other structures in otherwise wild lands.
Nowhere is that effort more intense than on the Arctic coastal plain of the North Slope of Alaska — a Maine-size stretch of open lands that is snow-blown and ice sheathed in winter, but a verdant breeding ground for caribou and millions of birds in summer.
Since oil was discovered 40 years ago, 1,000 square miles of the plain have become peppered with wells and laced with pipes. In response to research on caribou, pipelines were elevated 10 feet in hundreds of places so herds could pass unimpeded.
Now a study has for the first time assessed the impact on nesting birds from so-called subsidized predators -- the ravens, gulls and arctic foxes that thrive around the garbage bins, nesting sites and hiding places afforded by oil fields."