DAVID GREENE, host:
This is MORNING EDITION, from NPR News. Good morning. I'm David Greene.
RENEE MONTAGNE, host:
And I'm Renee Montagne.
In the Gulf of Mexico, BP is trying to choke off that oil leak by pumping mud down into the damaged well. The company began what's known as a top kill yesterday, and hopes to know today whether it's working. It's one of several developments surrounding this story. We begin with a look at how the oil is seeping deeper and deeper into Louisiana's fragile marshes, a critical habitat for birds, mammals and marine wildlife.
As NPR's David Schaper reports, some cleanup options may cause more damage.
DAVID SCHAPER: The scene here at the Venice Marina in Venice, Louisiana in the heart of the Mississippi Delta is one of summer serenity.
(Soundbite of water splashing)
SCHAPER: Fish jump under the sinking, late-afternoon sun while a warm breeze blows ripples over the water. It's a stark contrast to the sight of petroleum sliming the once-pristine marshes not far from this harbor, and that's what's on the minds of the teams of biologists steering their boats back in after surveying some of the damage.
Ms. MAURA WOOD (National Wildlife Federation): We were out in the bay, and there was this sheen of oil and globs of oil.
SCHAPER: Maura Wood works on coastal Louisiana restoration for the National Wildlife Federation.
Ms. WOOD: And right now, as you approach the marsh, it almost looks normal. But as you get closer, you see that the bottom of all the canes is coated with brown, sticky oil. And then you see that on the surface of the water, there's still globs of red and black and brown oil, almost as far as the eye can see.
SCHAPER: That oil can harm the canes, grasses and other flora of the marsh, first by suffocating the plants - the thick consistency of the oil coats them, not allowing the plants to breathe. Secondly, the oil's toxins poison the plants, says National Wildlife Federation senior biologist Doug Inkley.
Dr. DOUG INKLEY (Senior Biologist, National Wildlife Federation): With this oil coming in, if it is severe enough to kill the plants entirely, then these plants are going to decay, and what basically you take away is the entire root structure that helps to support that soil. And with the waves and the weather coming in, virtually, these wetlands disappear.
SCHAPER: And that's if you do nothing, right?
Dr. INKLEY: That's if you do nothing. And so what we need to try to do is find out what we can do, and there's no easy solution.
SCHAPER: Indeed, there are several ideas under consideration by local, state and federal officials, and each appears to have drawbacks, and some could do more harm than good. Soft, mucky peat-like soils hold Louisiana's coastal marshes together, and they are the Gulf's nurseries for fish, shrimp, crabs, oysters and other marine life, as well as the nesting grounds for pelicans and other birds. Rakes and pressure hoses like those used to clean the rocky and sandy Alaska shores after the Exxon Valdez spill would tear the Louisiana marshes apart. Heavy machinery is out of the question, and even people walking into the marshes might do as much damage as the oil.
Another idea, says Inkley, is to divert more water into the marshes.
Dr. INKLEY: Flooding of the marshes is one possible option, because you can try to lift the oil back up off of the plants and back up off the soil, to the extent that it's not too sticky. But that's also an issue.
SCHAPER: As is getting enough water to flood the marshes. Some parish officials might try vacuum-like suction devices as soon as this weekend, but there's no clear idea how well that would work. Thad Allen, the Coast Guard admiral who is heading up the federal government's response to the oil spill, has suggested the drastic-sounding step of prescribed burns to rid marshes of the toxic oil.
But the Wildlife Federation's Doug Inkley says burning is risky.
Dr. INKLEY: If it burns too low during a low tide type of time, then what you can end up with is killing the plants altogether. And that's just as bad as the oil killing the plants, because it can destroy the marsh. So there's no good options for cleaning it up. The best option is to keep it out of the marshes in the first place.
SCHAPER: But it's too late for that for many of the marshes, estuaries, islands and wetlands on the Louisiana coast, and there will likely be many more waves of oil washing up into them for months to come.
David Schaper, NPR News.
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