The Coast Guard has approved BP’s “top kill” plan to stop the oil leak in the Gulf of Mexico, but, even if it works, for much of Louisiana’s wildlife it will be too late. "It's the very worst-case scenario, for things like birds and mammals,” says James H. Cowan Jr., a professor at Louisiana State University. Oil kills wildlife in different ways: It suffocates grass; smothers coral, and sticks between birds’ feathers, rendering them unable to fly and leading them to ingest it as they try to clean themselves. Scientists have found 377 birds dead or incapacitated because of the oil, plus dozens of turtles and dolphins whose causes of death have not yet been determined; these are just a fraction of the overall animals affected. "Now that the stuff is really sort of coming ashore, it really is living up to its potential. It's certainly breached the sort of outer defense system of Louisiana,” says Cowan.