From TheMiamiHerald (Glen Garvin)
The oil was everywhere, long black sheets of it, 15 inches thick in some places. Even if you stepped in what looked like a clean patch of sand, it quickly and gooily puddled around your feet. And Wes Tunnell, as he surveyed the mess, had only one bleak thought: "Oh, my God, this is horrible! It's all gonna die!"
But it didn't. Thirty-one years since the worst oil spill in North American history blanketed 150 miles of Texas beach, tourists noisily splash in the surf and turtles drag themselves into the dunes to lay eggs.
"You look around and it's like the spill never happened," shrugs Tunnell, a marine biologist. "There's a lot of perplexity in it for many of us.
For Tunnell and others involved in the fight to contain the June 3, 1979, spill from Mexico's Ixtoc 1 offshore well in the Gulf of Campeche, the BP blowout in the Gulf of Mexico conjures an eerie sense of deja vu.
Like the BP spill, the Ixtoc disaster began with a burst of gas followed by an explosion and fire, followed by a relentless gush of oil that resisted all attempts to block it.
Plugs of mud and debris, chemical dispersants, booms skimming the surface of the water: Mexico's Pemex oil company tried them all, but still the spill inexorably crept ashore, first in southeast Mexico, later in Texas.
But if the BP spill seems to be repeating one truth already demonstrated in the Ixtoc spill - that human technology is no match for a high-pressure undersea oil blowout - scientists are hoping that it may eventually confirm another: that the environment has a stunning capacity to heal itself from manmade insults.
"The environment is amazingly resilient, more so than most people understand," says Luis A. Soto, a deep-sea biologist with advanced degrees from Florida State University and the University of Miami who teaches at the National Autonomous University of Mexico.
"To be honest, considering the magnitude of the spill, we thought the Ixtoc spill was going to have catastrophic effects for decades. ... But within a couple of years, almost everything was close to 100 percent normal again."
That kind of optimism was unthinkable at the time of the spill, which took nearly 10 months to cap. The 30,000 barrels of oil a day it spewed into the ocean obliterated practically every living thing in its path. As it washed ashore, in some zones marine life was reduced by 50 percent; in others, 80 percent. The female population of an already-endangered species of sea turtles known as Kemp's Ridley shrank to 300, perilously close to extinction.
What survived wasn't much better off. Soto, surveying fish and shrimp in the Mexican coastal waters near the spill, found them infested with tumors.
The sizable fishing industry in the area was practically shut down - not that the boats were able to make their way through the massive clumps of giant tar balls bobbing through the Gulf of Campeche anyway.
"There were a lot of those balls of oil at that time, and they could really mess up the machinery of your engines," recalls 62-year-old Isidro Vega Morales, who operates three fishing boats in Ciudad del Carmen, a Mexican port about 60 miles southeast of the Ixtoc oil well.
"There were so many balls, and so few fish, that after a while some of the fishermen started catching the balls instead. They'd melt the tar down into oil and sell it as a kind of sealant for other small fishing boats."
In Texas, meanwhile, tourism curdled.
Oil was so unavoidable on the popular beaches of Padre Island, just south of Corpus Christi, that hotels installed special mats outside along with signs pleading with guests to clean their feet rather than track tar into their rooms.
And scientists feared a less visible but more insidious effect of the spill: that it had killed off small organisms living at the tide line that form a crucial part of the marine food chain.
"These are things that most people never notice, some small segmented worms called amphipods, some little shrimp-like crustaceans," says Tunnell, associate director of the Harte Research Institute at Texas A&M University-Corpus Christi. "They were practically wiped out. And if they didn't recover, it would have drastically affected the food chain, from small fish and crabs up to shorebirds and beyond."
But after three months in which nothing went right, Texas had some good luck - or, to put it in a glass-half-empty way, Alabama and Mississippi had some bad luck. Hurricane Frederic, while plowing into those two states, sent tides of two-foot waves reeling into the Texas shoreline. Overnight, half the 3,900 tons of oil piled up on Texas beaches disappeared. And human clean-up efforts began putting a dent in the rest.
Even in Mexico, which had neither the resources nor the hurricanes of the United States, the oil began disappearing under a ferocious counterattack by nature. In the water, much of it evaporated; on beaches, the combined forces of pounding waves, ultraviolet light and petroleum-eating microbes broke it down.
"The environment in the Gulf of Mexico is used to coping with petroleum," says Tunnell. "The seabed is crisscrossed with petroleum reservoirs, and the equivalent of one to two supertankers full of oil leaks into the Gulf every year. The outcome of that is a huge population of bacteria that feed on oil and live along the shoreline."
The bacteria as well as other marine life forms along the shoreline got a boost from a strategy employed by both the United States and Mexico: to more or less give up on stopping the oil spill from reaching beaches while concentrating on keeping it out of estuaries and wetlands.
"Texas just made a superhuman effort to keep the oil away from rivers, with two or three or four layers of booms to skim it away," said Thomas C. Shirley, a biodiversity specialist at Texas A&M-Corpus Christi. "We know how to clean up beaches, and it's simple. It's just sand."
"But you get up into wetlands, where you're cleaning up shrubs and sea grasses, and it's far more difficult. Everything you're cleaning is alive, and you have to be careful not to do more harm than good."
By keeping oil out of rivers and lagoons, authorities ensured a steady stream of nutrients back into the coastal areas. And as the spill diminished, marine life had a baby boom.
"A lot of the fishermen around here will tell you that the fish never came back," says Vega Morales. "They'll say, 'Oh, in the old days, you could catch fish with your hat, it was so easy.' That's how we are, always talking about the one that got away. But the truth is, after maybe nine months or so, it was back to normal."
Soto, who followed the fish and shrimp population off Mexico closely, found to his surprise that for most species the numbers had returned to normal within two years.
"The catastrophic effects that everybody's looking for, those are mostly limited to the first months," he says. "Then you start looking in subsequent months, the long-range view, and it all diminishes. The pollution effect becomes more and more difficult to find .... It's like a radio signal, when you're close, it's strong. But when you start moving away, the signal starts to fade."
Even the physical evidence of the spill quickly began disappearing. Tunnell has been visiting Mexico regularly for 30 years, mapping the spilled Ixtoc oil on the country's beaches and coral reefs.
"In 1979, the islands around Veracruz looked like black doughnuts, there was so much oil clustered around them," he remembers. "It was 12 to 15 inches thick in some places. But as I came back over the years, it got harder and harder to find. After five to seven years, it was hard to see the outline, and by 2002, an unsuspecting person would have thought it was a rock ledge - it was covered with algae and shells and just looked like a normal part of the environment."
Even under water, where the sun can't help the oil break down, nature subverts it, says Mexican marine biodiversity analyst Jorge Brenner. "If you visit the coral reefs in the Gulf of Campeche, the tar has been covered with sea grass, algae and sediment," he says. "You actually have to dig a little bit to find it, although it's definitely there."
As much as the experts marvel at the way the environment recovered from the Ixtoc spill, none of them are shrugging off the BP disaster. Some larger species with longer life spans took years to recover from the Ixtoc spill. It wasn't until the late 1980s that the population of Kemp's Ridley turtles, which lay a couple of hundred eggs a year, as opposed to the millions produced by shrimp, started recovering. The immediate losses from an oil spill continue to ricochet through larger species for generations.
"I look at those oil-covered pelicans I see on the news every night," says Shirley, "and I think about all the chicks back on the beach that are left without a parent. Most of them are not going to make it, either."
And while the Ixtoc and BP spills are in many respects startlingly similar, they also have important differences - particularly the depth at which they occurred. The Ixtoc well was in relatively shallow waters, about 160 feet deep. Nobody knows what happens to oil at 30 times that depth.
"Do I think the environment has an amazing resilience? Yes, I see it every day as we patrol the shoreline," says Travis R. Clapp, a National Park Service resource manager who works at the Padre Island National Seashore. "But I'd be cautious about saying how quick the recovery from this spill is going to be. We're in a whole new ballgame here."
Links :
- Reuters : Deepwater spills and short attention spans
- TheGuardian : Dave Martin (AP) picture
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