VENICE, La. -- After several hours motoring through the bays and passes that web across the Mississippi River Delta, Bob Ford, a wildlife biologist with the Fish and Wildlife Service, spots a few brown pelicans and frigate birds perched on the remnants of a hurricane-ravaged barge platform in Redfish Bay.
As Ford's boat approaches, the birds fly away, and he watches them through his binoculars as they disappear across the taupe-gray water.
"At least one of those pelicans had a bit of oil on it," he says.
It is not enough to inhibit flying, but as the young bird preens it could ingest the oil.
"It will potentially get into the bloodstream," Ford says, and that could mean damage to the liver, kidney or lungs, and possibly death.
The juvenile brown pelican is one of hundreds of birds harmed by oil spreading from the ruptured Deepwater Horizon well, about 50 miles southeast of here. The 3,500 square-mile oil slick, which grows daily as oil continues to well up from 5,000 feet beneath the ocean's surface, is now reaching the islands of the Mississippi Delta, fringing wetlands with toxic black muck and coating wildlife that come into contact with it.
So far, workers have retrieved 584 animals -- 78 alive and 506 dead -- from the oil-stained coast. The count is lower than many biologists expected. On Tuesday, while BP PLC was preparing yet another strategy to plug the gusher, biologists found just one bird, another brown pelican. The day before -- Memorial Day -- five oiled seagulls were retrieved.
"We're seeing less than we thought," said Michael Downie, one of the leaders of FWS's wildlife recovery effort, standing in the operation's control room on a barge moored at the Pass a Loutre Wildlife Management Area, at the tip of the delta. "The birds are pretty good at staying away from the oil," he said. "And the oil is staying offshore, for the most part."
But on Tuesday, the first day of hurricane season, biologists sounded warnings that shifting winds could force the oil farther inland, where it could cause more damage -- and reach more species. Oil has already fouled islands south and west of the mouth of the Mississippi River, but now fingers of the slick are migrating to the east, toward Mississippi and Alabama.
"We're preparing for the worst," said Barry Forsythe, another leader of FWS's wildlife reconnaissance operation, standing on the deck of the barge in the battering midday Louisiana heat. "We hope it doesn't happen, but it's quite possible we'll have some oil push in."
Among the dead and injured so far are dolphins and sea turtles, which have washed ashore in several areas. But the death tally is dominated by birds.
Rhonda Murgatroyd, managing director for Wildlife Response Services LLC, which BP has hired to help with wildlife rescue, is worried that she will soon start finding far more birds in trouble.
"My greatest fear? Oiled colonies," she said.
Forsythe said that when the next wave of oil comes, his team would be ready.
About 340 FWS employees, from all over the country, are on guard at the agency's two oil spill response centers in Houma, La. and Mobile, Ala. Other federal and state agencies, including the National Oceanic and Atmospheric Administration and the Louisiana Department of Wildlife and Fisheries, are also participating in the oil spill response effort.
In all, 17 federal staging areas stand ready to protect sensitive shorelines, from Grand Isle, La. to Pensacola, Fla. Using daily wind and current projections from NOAA, Forsythe and his team identify where the oil is moving and dispatch wildlife rescuers to those sites to search for birds and other wildlife that may be in need of help.
But even with a coordinated multi-agency effort, finding wildlife is a considerable challenge in the delta, with its huge maze of islands and passes and bays. And retrieving oiled animals is a delicate operation, with wildlife handlers often having to make tough decisions -- particularly when it comes to birds.
"It's a hard choice to decide how much oil is enough to bring them into the rehab center," which is at nearby Fort Jackson, Forsythe said. And walking to a nest can push the oil further into the soil, where it can damage the roots of wetland plants.
At the same time, it is important to bring in the birds quickly, because oiled birds can overheat, Forsythe added. The average time between capturing a bird and delivering it to the rehabilitation center is about one hour, he said.
Some birds escape capture, even heavily oiled ones, added Ford. "It takes a lot to get them," he said. "Sometimes we catch them after a day or two."
Shorebirds are most at risk, said Rowan Gould, FWS's acting director, who visited the recon barge for the first time on Tuesday.
"They're probably in the most vulnerable position," said Gould, who began his career as a wildlife biologist. Migratory birds that visit the Louisiana marsh islands each spring had already moved north. "They're lucky," he said.
Most of the birds harmed by the spill are native brown pelicans, which were just removed from the Endangered Species List last year. Yet despite the new risks from the spill, Gould said the pelican probably will not be re-added to the endangered list.
"I don't think so, because there are so many other populations around," Gould said.
He noted that just last year, Interior Secretary Ken Salazar and then-FWS director Sam Hamilton, who died in February, were visiting the area to celebrate the brown pelican's recovery. "Very ironic," he said.
Some of the delta's feathered residents have taken refuge in unusual places.
On a rusty, capsized barge ripped from its moors by Hurricane Katrina and now beached against a small island, a few birds tend to their nests atop its deck in the languid, late afternoon sun.
"That's about the most interesting use of a barge I've ever seen," says Murgatroyd, adding that birds are smarter than people think. "I teach fifth graders about birds, and I always tell them, if someone calls you a bird-brain, say, 'Thank you very much.'"
'A lot of area to cover'
While oil spills have occurred in the Gulf of Mexico before, the Deepwater Horizon slick is both bigger and harder to contain than any previous accident, officials said. The sheer volume of the spill, estimated at about 20 million gallons so far, means that new plumes of oil could advance toward the shore for months. Keeping tabs on where the oil is going, and what wildlife might be in harm's way, requires 34 men and women, a large collection of GPS units and even larger reserves of resourcefulness.
"There's a lot of area to cover, and a lot of storms coming through," Downie says. "And on top of all that, communications are really hard. Cell phones do work occasionally -- if you stand on your toes."
"I had no idea a spill could get this big," added Murgatroyd, whose company, Wildlife Response Services LLC, has rescued wildlife affected by several spills over the years, including January's Port Arthur, Texas, spill, caused by a collision between a barge and an oil tanker.
The best protection for birds is to keep the oil from reaching wetlands in the first place, officials noted. BP contractors have encircled many islands with red containment booms designed to keep oil out. But winds and waves can easily move them, and they must be monitored daily to make sure they stay in place.
"All we can do to protect those marshes is time well spent," Gould said.
The Interior Department and several Gulf Coast state governments have asked the Army Corps of Engineers to build new barrier islands to keep the oil from reaching the coast. The corps is mulling the idea, but it remains unkown how effective it would be. Island building has never been tried in response to an oil spill.
While much work remains to be done, all the human activity on the water could inadvertently stress the birds even more, Murgatroyd said.
"These birds aren't used to seeing so many people," she says, scanning a birdless island in Redfish Bay from the stern of a small fishing boat, as another vessel passes nearby. "We've by default hazed them."
Worsening land loss?
The oiling of wetlands is not only a threat to wildlife. It could also accelerate the loss of land along the shrinking Louisiana coast.
Scientists estimate Louisiana has lost about 1.2 million acres over the past century, and the subsidence continues at a rate equaling 32 football fields every 24 hours. The shrinking shoreline is a consequence of the vast system of levees and canals built over the 20th century by the federal government to aid navigation and flood protection. While the elaborate plumbing system has aided the region's economy, it also has cut off the Mississippi River from its delta, starving the marshes of the sediment needed to build land mass (Land Letter, Aug. 20, 2009).
Ron DeLaune, a researcher with the Wetland Biogeochemistry Institute at Louisiana State University who has studied the impacts of oil spills on wetlands, said the Louisiana coast could see even greater losses if the contamination causes a mass die-off of smooth cord grass and other vegetation that helps hold marsh soils in place.
"It could kill marsh vegetation, and if it does, it would cause marsh deterioration and it could aggravate the wetland loss," he said. "I'm concerned about how much of our area will be impacted, and how long."
It remains unclear how extensive the damage will be, DeLaune added. If the oil only coats the stems of the plants, they can survive. But if it coats the leaves, blocking photosynthesis, they will die.
"The degree of this impact depends on the length of exposure, and what portion of the vegetation is exposed to oil," he explained.
In Louisiana, the tidal range is not very high, and the oil may not reach the leaves -- unless strong winds push water levels higher, he said.
A die-off of wetland plants could cause some areas to sink even faster, as gaps form in the soil where roots once were, added Irv Mendelssohn, a plant ecologist with Louisiana State University in Baton Rouge who specializes in coastal ecosystems.
"It's like taking the air out of a balloon," he said. "If the plants die, not only are the roots no longer able to hold the soil, and therefore it's more subject to erosion, the land actually sinks. That's enough to stress any regrowth of new plants after the oil spill. They can't get re-established."
Compounding the problem, drought has already killed many salt marsh plants, and in some areas the soil has sunk by six or seven inches, he said. As those areas fill with water, forming small ponds, it becomes too deep for new marsh plants to take root, he added.
"The plants that exist there are just hanging on. A lot of salt marshes are like that -- they're all through the Louisiana delta plain, areas where the marsh is falling apart because the plants can't hold on any longer, and the ground is sinking," Mendelssohn said. "You'll see marshes that have a lot of small islands, with marsh surrounded by water. It looks all broken up. Those plants are highly stressed."
Mendelssohn said he and other researchers would begin monitoring the extent of the damage in the coming weeks and months, including what effects the spill has had on the broader ecosystem.
With so much oil still offshore, and the Deepwater Horizon well still gushing, the long-term ecological impacts are largely unknown. "Figuring out how the oil is going to impact the ecosystem over time -- that's going to be the challenge," said Ford, the FWS wildlife biologist.
Another economic blow
Uncertainty over the effects of the spill is also weighing on the minds of local residents. Just as south Louisiana's economy had begun to rebound from hurricanes Katrina and Rita, the region now must face yet another blow to its world-class fisheries -- this time, at the expense of another of its major industries.
Along the road to Venice, which follows the Mississippi River to its mouth, clues to the collective anxiety of the delta region abound. Just down the road from the Chevron Oronite plant, which makes fuel additives, and past a pair of nodding oil pumps, a small, colorful sign stands out in front of a private home: "Damn BP. God Bless America."
Several miles north, not far from where rural Plaquemines Parish gives way to the urban fringes of New Orleans, another sign urges drivers to "Support Billy's barrier island plan" -- a reference to the barrier island proposal, first put forth by Plaquemines Parish President Billy Nungesser.
These communities have a lot to lose. Commercial fishing produces about 1.27 billion pounds of fish and shellfish in the Gulf each year, with a dockside value of over $659 million, and generates about 185,000 jobs (Land Letter, May 27).
This week, NOAA expanded its closure of the Gulf fishing grounds to include parts of eastern Alabama and the western tip of Florida. The closed area now encompasses 75,920 square miles -- about 31 percent of federal waters in the Gulf of Mexico, according to NOAA.
Local residents, many of whom have lived on the delta for generations, are bracing for the worst.
"I'm sick," said Steve Domino, who runs a small marina with his father, sitting in his father's boat as it plies the waters of one of the delta's many passes. "Look what it's doing to affect the wildlife, and the fishing, shrimping, crabbing, oysters -- the whole fishing industry. It's so much loss at one time, it's hard to swallow."
Click here for updated information about FWS's response to the spill.
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