Among the animals threatened by the spill is the brown pelican, which only came off the endangered species list this past November, CBS News Special Contributor Jeff Corwin reports.
Complete Coverage: Disaster in the Gulf
Just 10 miles from the nesting grounds of one noisy colony of brown pelicans, more than 3 million gallons of oil are lurking. That threatens species already decimated by the disappearance of marshlands.
Just how fast are they shrinking?
"If we talk for 20 minutes, at the end of that we will have lost a football field or two of land," the Louisiana Audubon Society's Melanie Driscoll said.
Coastal Louisiana used to be half land, half water. In 1956, 5,850 square miles of the coastline was land, and 5,585 square miles were water.
Now the coastline is more than 61 percent water - with 4,406 square miles land and 6,952 square miles water - losing about 25 square miles of land each year.
The pelicans nest on one coastal island so they can dive bomb waters rich in small fish, such as mullet and herring, their main source of food.
"The birds are flying out from this island, diving into the water to catch that food," said Greg Butcher, director of bird conservation for the National Audubon Society.
Oil in the water could poison the pelicans' food supply. Oil-saturated feathers also provide no insulation from the cold and would rob them of their ability to float. The pelicans could even drown.
At a bird rehabilitation center, workers have already nursed one oiled pelican back to health.
"Right now they don't want to leave their nest," said Dr. Erica Miller. "That means they're going to stay, unfortunately, where the oil is."
Today, there are about 50,000 pelicans, but in 1963 the species was pushed to regional extinction. Their recovery is considered one of Louisiana's greatest conservation success stories, but with this impending threat, the brown pelican may be in jeopardy once again.
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