The fi ery destruction of an oil drilling platform in the Gulf of Mexico on 20 April may have triggered one of the worst environmental disasters in U.S. history. The impact of the crisis, which began with the deaths of 11 workers and then simmered for several days before an expanding oil slick grabbed worldwide attention, promises to test the federal government’s ability to protect habitat, wildlife, and the economic well-being of a four-state region on a scale never before imagined. Secretary Ken Salazar of the Department of the Interior declared on 2 May that the government’s role is to “keep its boot on the neck of BP,” the British-based oil giant that had contracted to use the drilling rig, Deepwater Horizon. And BP CEO Tony Hayward said his company “will absolutely be paying for the cleanup operation. There is no doubt about that. It’s our responsibility—we accept it fully.” As Science went to press, severe weather was slowing the spread of the oil to the shore. BP offi cials were hoping to deploy an oiltopping containment vessel in the coming days. Biologists have their fi ngers crossed, fretting over a blow at the worst possible time to an already fragile ecosystem. “I don’t want to be alarmist, but I’m alarmed,” says ornithologist James Remsen of Louisiana State University (LSU), Baton Rouge. As a precautionary step to ensure the safety of the food supply, the National Oceanic and Atmospheric Administration (NOAA) has imposed a 10-day ban on commercial fi shing in the region.