Gulf of Mexico recovery depends on marsh grass survival
By David A. Fahrenthold
Washington Post / August 2, 2010 ON TAMBOUR BAY, La. — In the next act of the drama of the Gulf of Mexico oil spill, two of the most important heroes don’t look like heroes. They are just thin green stalks, sticking out of blackened patches of grass. They are cordgrass and wiregrass, common species that wave in the winds in south Louisiana’s coastal marshes. Except, in some places, they aren’t waving anymore: Where oil has sloshed into the marshes, their stalks are matted and gooey and, perhaps, on their way to a slow death. What happens next — whether these two grasses rebound or vanish — will be a very important piece of the gulf’s larger environmental story. Now that the well has been capped, the next question is whether marsh and marine ecosystems can shrug off the oil’s damage, or whether it will leave them with lasting wounds. “Many of us are much more worried about the marsh than we are about fish and shrimp and all that,’’ said Denise Reed, a wetlands expert at the University of New Orleans. “If those plants die, they don’t come back. And the marsh is gone.’’ Louisiana’s coastal marshes are vital to ecosystems that extend far into deep, open water: They shelter juvenile shrimp, crabs, and fish until these creatures are large enough to venture into open water. For these places, grasses are as vital as water. Their roots hold the land together, giving support to loose, wet sediment that would otherwise erode. “They are the marsh, basically,’’ said Andy Nyman of Louisiana State University. “Once they die … it just floats away.’’ Humans, too, depend on the grasses, since the marshes are a natural barrier against storm surges headed toward New Orleans. Already, there are about 200 square miles of oiled coastline in Louisiana alone, said Robert Barham, secretary of the state’s Department of Wildlife and Fisheries. He said most of that is marshland, which means around 5 percent of the state’s 3,900 square miles of marsh is oily. That number may not seem overwhelming, but Louisiana is already losing 24 square miles of wetlands to erosion every year. Scientists say the state cannot afford to lose another large chunk all at once. The question now is: How much will die? …
