The oil that began washing ashore Friday in Louisiana could devastate one of the richest coastal ecosystems in the country and cripple a major source of the nation's seafood, a top Maryland scientist warns.
But Donald F. Boesch, president of the University of Maryland Center for Environmental Science, said a rush to clean up oil smothering sensitive wetlands could risk further damage if not done right.
Fish and shellfish, shorebirds and waterfowl, sea turtles and a host of other wildlife are at risk from the more than 200,000 gallons of oil pumping daily out of the ruptured well in the Gulf of Mexico 50 miles off the Louisiana coast. Animal rescuers on the Gulf Coast said the spill could be "the worst environmental disaster in recent U.S. history." Efforts this week to halt the leak proved futile, and authorities have said it might take up to three months to shut it off.
The fact that the spill will go on for weeks or months could hamper recovery and amplify damage, said Boesch, a New Orleans native who went to school there and spent a decade as a marine biologist in Louisiana before coming to Maryland.
Winds are blowing the spreading oil northward toward shore, targeting fragile barrier islands and Louisiana's vast marshlands — about 40 percent of all the coastal wetlands in the lower 48 states. Those marshes — vital habitat and nursery grounds for fish, shellfish, birds and other wildlife — could be seriously damaged if coated with petroleum.
Because the vast majority of commercially valuable fish and shellfish caught in the Gulf depend on wetlands for some part of their life cycle, the spill could have a devastating impact on the region's seafood and recreational fishing industries.
"Spring is an important time for reproduction of marine life," Boesch noted.
Landings of shrimp, crabs and oysters all could be affected by the spill, according to the National Oceanic and Atmospheric Administration. The Gulf is the source of 73 percent of the shrimp caught in this country, 26 percent of the blue crabs and two-thirds of the oysters. Gulf crustaceans and shellfish make up an important component of the mid-Atlantic seafood market, supplementing what's caught in the Chesapeake Bay.
Boesch said he's particularly concerned about the spill's impact on oyster beds in Louisiana. Even if they aren't killed by the pollution, they may become contaminated with toxic ingredients of petroleum, such as benzene, he said. And even if only a fraction of the beds are closed by the spill, consumers may shun Gulf seafood, exacerbating the economic impact.
"No one wants to eat oily oysters," he said.
The marshes also hold "an incredible variety and diversity of birds," Boesch said. One he's particularly worried about is the brown pelican, Louisiana's state bird, a fish-eating shore dweller that survived near-elimination decades ago from exposure to the since-banned pesticide DDT.
Miles of floating booms are being deployed to keep the oil from land, and chemicals are being sprayed on the slick to break up the oil. Volunteers and cleanup contractors are rushing to the region to aid with injured wildlife and cleanup efforts. But should oil coat the wetlands, Boesch said, he hopes remediation proceeds with care.
"Once it gets into these marshes, the natural feeling and public pressure is, ‘You've got to go clean it out, get it out,'" Boesch said. But unleashing hordes of volunteers to soak up spilled fuel tramples grasses and drives the oil deeper into the muck. Though the oil may coat and kill existing marsh vegetation, it's likely to regenerate in a fairly short period of time, he said.
Boesch's warning was echoed by Jonathan McKnight, associate director of wildlife for the Maryland Department of Natural Resources, who helped coordinate cleanup a decade ago of a 140,000-gallon oil spill from a ruptured pipeline in Southern Maryland.
The marshes along the Patuxent River at Chalk Point "got trashed" with thick, gloppy fuel oil, McKnight recalled. "We trashed them further cleaning it up. ...You send in hundreds of guys in yellow suits with rags to mop it all up. That's not good for them, either."
The April 2000 Patuxent spill — just a fraction the size of what has already leaked into the Gulf — fouled 76 acres of wetlands and 10 acres of beach, killed an estimated 600 ruddy ducks and other birds, hundreds of muskrats and more than 100 diamondback terrapins. Biologists also figured the surviving terrapins suffered a drop in reproduction as eggs they laid in the oil-tainted marsh failed to hatch.
McKnight said he'd worry first about sea turtles and shorebirds along the Gulf Coast. There are at least five species of endangered or threatened turtles in the Gulf, including the Kemp's Ridley. Biologists note that the only place where the Kemp's Ridley nests is in the western Gulf, from Texas to the mouth of the Mississippi River.
"We are entering the prime time within the Ridley nesting season in which adult females will be in nearshore waters nesting three to four times every 14 to 21 days," Andre Landry Jr. of Texas A&M University's Sea Turtle and Fisheries Ecology Research Lab noted in a news release.
Moby Solangi, director of the Institute for Marine Mammal Studies, said this is also birthing season for the roughly 5,000 dolphins along the Mississippi and Louisiana coasts. "It's very bad timing. We're looking at a colossal tragedy."
Ten sites that the American Bird Conservancy considers globally important bird areas are directly in the path of the oil slick, the group said.
"This spill spells disaster for birds in this region and beyond," said ABC President George Fenwick. "It is ironic that next weekend is International Migratory Bird Day. At a time when we should be celebrating the beauty and wonder of migratory birds, we could be mourning the worst environmental disaster in recent U.S. history."
Despite the risk that the cleanup might further damage wetlands, McKnight said he wouldn't second-guess those directing the spill response there, especially since the oil might keep coming ashore for weeks.
"You've got to immobilize the oil somehow, and if it means doing more damage to an already damaged marsh, that's what you've got to do," he said. "The people who are there need to make tough choices."
Edward Bouwer, chairman of environmental engineering at the Johns Hopkins University, said oil can be deadly to animals and plants, but its most toxic effects tend to diminish relatively quickly — six months to two or three years, he estimated — as the fuel degrades under exposure to the elements and to bacteria that consume it.
Bouwer, who was an adviser during the cleanup of the 1989 Exxon Valdez tanker spill in Alaska, said one technique that appeared to hasten the degradation there was spraying the contaminated areas with fertilizer to stimulate growth of the bacteria that fed on the oil.
"It does a lot of damage in the short term," he said. "Usually, when you go back, 10 years after, it does recover nicely."
The Gulf spill has prompted Obama administration officials to put on hold plans to open up new areas off the Atlantic and Gulf coasts for oil and gas exploration, which could include areas off Maryland's shore. Boesch noted that one tract off Virginia's coast is nearing readiness to be put up for leasing by energy companies.
"That area is closer actually to Ocean City, Md., than it is to Virginia Beach," Boesch said, "so it's not simply a Virginia issue. Maryland's got just as big a stake as Virginia."
The Associated Press contributed to this article.