By David A. Fahrenthold - Washington Post
How dead is the Gulf of Mexico?
It is perhaps the most important question of the BP oil spill -- but scientists dont appear close to answering it despite a historically vast effort.
In the 2 1/2 months since the spill began the gulf has been examined by an armada of researchers -- from federal agencies universities and nonprofit groups. They have brought back vivid snapshots of a sea under stress: sharks and other deep-water fish suddenly appearing near shore oil-soaked marshes turning deathly brown clouds of oil swirling in deep water.
But with key gaps remaining in their data there is wide disagreement about the big picture. Some researchers have concluded that the gulf is being spared an ecological disaster. Others think ecosystems that were already in trouble before the spill are now being pushed toward a brink.
The distribution of the oil its bigger and uglier than we had hoped said Roger Helm a U.S. Fish and Wildlife Service official and the lead scientist studying the spill for the Interior Department. The possibility of having significant changes in the food chain over some period of time is very real. The possibility of marshes disappearing . . . is very real.
Helm said that his prognosis for the spill had worsened in the past week -- as the amount of oily shoreline increased from Louisiana to Florida despite cleanup efforts. This just outstrips everybodys capability to clean it up he said.
This research has mainly occurred in the background as public attention has focused on the open-heart surgery at BPs leaking wellhead.
The patient is a 600000-square-mile sea which contains swirling currents sun-baked salt marshes and dark cold canyons patrolled by sperm whales. Complicating matters is that even before the spill began in late April the patient was already sick.
In recent years Louisiana has been losing a football fields worth of its fertile marshes to erosion every 38 minutes. In the gulf itself pollutants coming from the Mississippis vast watershed helped feed a low-oxygen dead zone bigger than the entire Chesapeake Bay. Measuring the spills damage then requires distinguishing it from the damage done by these other man-made problems.
So far even the simplest-sounding attempts to measure the spills impact have turned out to be complex.
The official toll of dead birds is about 1200 a fraction of the 35000 discovered after the Exxon Valdez spill in 1989. But this too has been called into question. Officials can only count the birds they can find and many think a number of oily birds have sought refuge in the marshes.
Its an instinctive response: Theyre hiding from predators while they recover said Kerry St. P head of a government program that oversees Louisianas Barataria Bay marshes. They plan to recover of course and they dont. They just die.
Other scientists have focused on more subjective measures of the gulfs health -- not counting the dead but studying the behavior of wildlife the movements of oil and the state of larger ecosystems. For them solid answers are even more elusive.
For example: Is the oil killing off Louisianas coastal marshes? state officials have said in interviews that theyve seen it coating the grasses and mangroves that hold the regions land in place.
The marsh grasses the canes the mangrove are dying. Theyre stressed and dying now said Robert Barham secretary of the states Department of Wildlife and Fisheries. Theres very visible evidence that the ecosystem is changed.
But Paul Kemp of the National Audubon Society said he flew over the same area and saw a different picture: The oils damage was relatively small at least in comparison with the marshs existing problems.
Here we have a patient thats dying of cancer you know and now they have a sunburn too Kemp said. What will kill coastal Louisiana is not this oil spill. What will kill coastal Louisiana is what was killing it before this oil spill including erosion and river-control projects that have reduced the buildup of new land.
Further offshore federal scientists and university researchers have disagreed about the existence of plumes or clouds of dissolved or submerged oil. Several educators have reported finding underwater oil dozens of miles from the spill: Sometimes they reported it was so well dissolved that the water appeared clear. In other situations they found what they thought to be oil globs the size of golf balls.
Just around the leaking BP wellhead a Texas A&M University scientist reported finding pockets of water with very low dissolved oxygen. That might be a sign that bacteria were consuming oil from the spill -- but in the process the water became suffocating for other sea life.
The government has presented a very different picture of the deep gulf.
An official at the National Oceanic and Atmospheric Administration said his agency had found evidence of significant submerged oil -- 1 to 2 parts per million -- from the BP spill only within six miles of the well. In addition the U.S. Environmental Protection Agency has said it has not seen large scale problems with low dissolved oxygen around the submerged oil in the gulf.
Doug Inkley senior scientist at the National Wildlife Federation said he did not think the government had studied these areas well enough yet.
Ive been frustrated with the calm reassurances that weve been receiving because . . . I dont know what theyre based on Inkley said. In particular he said he was worried that submerged oil might kill deep-water coral colonies that had grown over the course of centuries.
Think of going and cutting down a giant Sequoia tree. . . . If these corals are killed then those areas will be vacant for some time Inkley said.
For those who study fish -- literally moving targets -- the data so far are a confusing hash of anecdotes and sightings.
In Sarasota Fla. scientists found an 11-foot tiger shark normally an open-water fish drifting near the surf. That plus sightings of whale sharks and other creatures outside their normal environmental range raised concerns that oily water or low oxygen in the central gulf might be driving fish toward land.
It would be like to these fish almost like an island a huge island rising up in the middle of the gulf said Bob Hueter of the Mote Marine Laboratory in Sarasota. Seeing this and other strange patterns in fish Hueter said I just all of a sudden just felt this impending sense of doom that the place that I loved was going to be changed in a very dramatic way.
Federal scientists however say that theyve seen evidence that even plankton -- some of the smallest most sensitive creatures in the gulf -- are living in the area around the leaking well.
Right now said John Valentine who studies the gulf from the Dauphin Island Sea Lab in Alabama we should be more impressed by what we dont know than what we do know.
