Oil Spill Hammers Brown Pelicans
Removed from the endangered species list only last year, Louisiana’s charismatic state bird takes a hit in the Gulf of Mexico
FOR MANY PEOPLE, the most enduring—and disturbing—memories of this year’s Gulf of Mexico disaster are likely to be the images of oil-soaked seabirds splashed across news media almost daily. And of these, the most upsetting of all tended to show brown pelicans, large, elegant and tremendously popular birds that have become icons for the U.S. Gulf Coast.
As of mid-summer, brown pelicans also were the bird species hit hardest by the spill: 58 percent of all dead or injured birds collected up to that point were pelicans, according to U.S. Fish and Wildlife Service (FWS) statistics. That worries some environmentalists. A rare conservation success story, the bird was removed from the federal endangered species list just last year. “It’s a species we’re keeping a close eye on,” says biologist Kelly Hornaday of the FWS endangered species program.
The timing of the spill could not have been worse: Pelicans, which nest colonially on offshore barrier islands, were at the start of their annual nesting season when the oil rig exploded. According to Hornaday, between 25,000 and 33,000 pairs of pelicans breed on islands off the U.S. Gulf Coast; Louisiana alone hosts between 8,000 and 16,000 pairs depending on the year. “The majority of the nesting islands hit by oil are in Louisiana,” she says. On July 14, biologists from the Cornell Lab of Ornithology reported finding at least 300 oiled pelicans on Raccoon Island alone.
Pelecanus occidentalis is unusual among the world’s eight pelican species. Along with the Peruvian pelican—a new species until recently considered the same as the brown pelican—it is the only one that lives strictly in coastal habitats, never venturing more than about 20 miles inland or out to sea.
Brown pelicans feed exclusively on fish they capture by diving headfirst into the water. The birds have excellent eyesight and can spot fish from as high as 60 feet. After nabbing their catch, pelicans scoop or dip the fish into their pouches, rise to the water’s surface, tilt their bills forward to drain the water, then toss their heads up and back to swallow. It turns out to be true that a pelican’s “bill can hold more than his belly can”: The bird’s pouch can accommodate about three gallons of water while its stomach holds only about one.
Unlike most birds, which keep their eggs warm with the skin of their breasts, pelicans incubate eggs with their feet, holding them under webs that stretch from the front toes to the hind toe. This unusual incubation method, along with their seafood diet, made pelicans particularly vulnerable to the pesticide DDT, which the birds picked up from contaminated fish. Because a metabolite of DDT—DDE—causes the eggshells of birds to thin, pelican parents accidentally cracked their eggs while attempting to incubate them. DDT and other pesticides, combined with shooting the birds for their feathers during the early 20th century, led to population crashes by the late 1950s. Pelicans disappeared entirely from the Pelican State of Louisiana.
In 1970, FWS listed the brown pelican as endangered throughout its range. A 1972 ban on DDT—along with transplanting thousands of chicks from Florida to Louisiana—led to remarkable population recoveries. In 1985, Atlantic coast populations of the bird were removed from the endangered species list. In November 2009, the species was removed from the list completely. “They’ve been doing very well,” says Hornaday. “Annual surveys by our state partners show either stable or increasing numbers with good nesting success.”
The oil spill could change that. As of mid-August, the pelican nesting season was coming to an end, and it looked like BP was about to shut down the well for good. “But there are still millions of gallons of oil floating around out there,” noted Mike Parr, a vice president of the American Bird Conservancy who had just completed a six-day visit to the gulf. “After the breeding season, pelicans start moving around a lot more,” he added, “and from what we observed, the boom they’re using to keep oil out of critical areas is hopeless. It doesn’t stand up to even moderate weather.” Meanwhile, the region was about to enter peak hurricane season.
Could the Pelican State once again lose its pelicans? Hornaday is cautiously optimistic. “The species may take a hit for a few years,” she says. But as its recovery in Louisiana shows, “this is a pretty resilient bird.” Brown pelicans evolved to cope with challenges such as hurricanes and periodic crashes in prey caused by El Niño, she adds. “These birds are adapted to boom and bust kinds of cycles.”
Laura Tangley is a National Wildlife senior editor.
http://www.nwf.org/News-and-Magazines/National-Wildlife/Birds/Archives/2010/Oil-Spill-Hammers-Brown-Pelicans.aspx
Oil Spill Threatens Migratory Birds
As millions of birds head for the biggest spill in U.S. history, federal and nonprofit groups work with farmers to create safe alternative habitats.
The BP oil spill has contaminated huge swaths of some of the continent’s most critical bird habitat. Yet scientists say that, given the scale of the disaster, the toll of dead and injured birds has been lower than they initially expected. Compared to previous spills like the Exxon Valdez, which was much smaller, “our numbers have not been very dramatic,” says U.S. Fish and Wildlife Service (FWS) biologist Gary Edwards, deputy regional director of the service’s Alaska region recently deployed in Louisiana.
One reason may be that most birds that die do so in remote wetlands or far out at sea and are never located. In addition, a combination of favorable tides and winds, along with the southerly outflow of the Mississippi River, kept the bulk of the oil offshore during the early stages of the spill. This gave most spring migrants a chance to get past the danger zone and arrive safely at summer breeding grounds in the northern United States and Canada.
But that soon may change.
Millions of shorebirds, waterfowl and other birds are flying into the Gulf region as fall migration gets under way. Some, such as shorebirds and songbirds, will be making short stops before setting off on long flights across the Gulf of Mexico to Central and South America. Others, including many ducks and geese, will spend the entire winter along the coast.
Having traveled hundreds, even thousands, of miles, all of these birds will be in desperate need of food and safe places to rest. But instead, they are “heading right for the biggest oil spill in this nation’s history,” says Paul Schmidt, FWS assistant director for migratory birds. “For more than a century,” he adds, “we have worked to protect and restore migratory bird populations in North America. This conservation legacy is now jeopardized by the oil spill.”
According to Schmidt, the U.S. Gulf Coast provides food and shelter to millions of birds of hundreds of species. “We estimate that literally hundreds of millions of birds use this area some time during their life cycle,” he says. Straddling the Mississippi Flyway, one of the most important migratory bird corridors on Earth, the region hosts during their twice yearly migrations a major portion of all birds that breed in North America.
At Risk: Shorebirds
During migration, vast numbers of shorebirds stop in the Gulf region to replenish critical fat reserves by feeding on beaches and in wetlands, many now polluted by oil. They include sandpipers, dunlins, plovers, dowitchers, greater and lesser yellowlegs and red knots.
FWS has listed one plover, the piping plover, as an endangered species throughout much of its range. Piping plovers already have been spotted in the spill zone. Their numbers are expected to peak in August and September, and some will stay the entire winter.
At Risk: Waterfowl
Tom Moorman, director of conservation planning for the southern region of Ducks Unlimited, calls the Gulf Coast “the most important wintering area for waterfowl in North America.”
Up to 13.7 million ducks and 1.5 million geese spend part or all of the winter in the region, dabbling for food near the surface of the water or diving beneath it. These species include red-heads, blue-winged teal, gadwalls, northern pintails and snow geese.
One duck of particular concern is the lesser scaup. “These birds have been declining for years, and no one knows exactly why,” says NWF senior scientist Doug Inkley.
According to Moorman, more than a third of the continent’s population of lesser scaup winter in the Gulf region—up to 1.4 million birds in some years. Scheduled to arrive in November, when they’ll begin feeding in shallow offshore waters, “tens of thousands of scaup could die” if they dive into oil-contaminated water.
If oil kills their prey—dwarf surf clams—the birds are likely to move to areas where they can find food. One of the worst scenarios, says Moorman, would be if the ducks ate filter-feeding clams that had taken in oil. The hydrocarbons contained in oil could cause major physiological damage or impair future reproduction.
At Risk: Loons
About half the common loons that breed in the Midwestern United States winter along the Gulf Coast. They feed only on the water. Most at risk are young loons that will stay in the Gulf two to four years before flying back north.
Other birds that winter in or pass through the Gulf region during fall include grebes, cormorants, several species of tern, white pelicans and many songbird species. Year-round residents increasingly at risk include many herons and egrets.
Oil Spill Worsening Wetlands Loss
Inkley and Moorman point out that the BP spill is just the latest major insult to the Gulf’s critical bird habitats. “The region’s wetlands were created and are maintained by sediments carried downstream and deposited by the Mississippi River,” says Inkley. Yet through actions such as building levees and carving out canals, “we’ve nearly stopped those natural processes and have done very little to rebuild the marshes.”
Over the past century, coastal Louisiana has lost some 1.2 million acres of wetlands, says Moorman—nearly half of what it originally had. He fears the oil spill may accelerate this process.
A Helping Hand for Migrants
To try and minimize harm to migrating and overwintering birds, federal agencies are teaming up with conservation groups as well as farmers, ranchers and other large landowners to improve, restore and create new wetland habitat and provide sources of food away from oil-contaminated zones.
At a July 2 press conference, Schmidt described several soon-be-be-launched efforts by FWS to “minimize the entrance of oil into managed habitats along the Gulf and enhance the availability of migratory bird food resources outside oil-impacted areas”—primarily by flooding farm fields. Service workers also may try and haze birds out of contaminated areas using firecrackers, Mylar tape and other measures. In addition, said Schmidt, the presence of hundreds of people moving around oiled areas as they try to clean them “will certainly serve as a distraction or detractor for birds.”
The U.S. Department of Agriculture’s Natural Resources Conservation Service is taking similar steps on lands within the federal Wetlands Reserve Program and on private agricultural lands in portions of eight states: Alabama, Arkansas, Georgia, Florida, Louisiana, Mississippi, Missouri and Texas. Dubbed the Migratory Bird Habitat Initiative, the project is paying farmers to flood cultivated lands—particularly rice fields—to create new clean habitat for migrating shorebirds and wintering waterfowl.
Being “Realistic”
But these efforts have limits. “We think we can have localized effects that will prevent some oiling and provide some benefits to migratory birds,” Schmidt said at the press conference. But “we’re also realistic,” he added. “We won’t be able to dramatically affect migrations in any major way, shape or form. The birds are still expected to do what they do in a natural cycle.”
http://www.nwf.org/News-and-Magazines/National-Wildlife/Birds/Archives/2010/Oil-Fall-Migration.aspx
Can We Rescue Oiled Wildlife?
New research indicates that the answer is a cautious yes, although spills in the Gulf of Mexico and elsewhere suggest considerable improvement is still needed.
A MONTH AFTER AN EXPLOSION on a deepwater oil-drilling platform in the Gulf of Mexico unleashed the biggest oil spill in United States history, the oil began to creep into Louisiana’s coastal marshes. It threatened crabs and oysters. It lapped against the stalks of marsh grass, choking off the roots’ oxygen and threatening the lifeblood of this richly productive ecosystem. Dead jellyfish bobbed offshore, their clear globes stained with oil. And as pelicansdive-bombed for fish, they emerged with a coating of sludge. Watching one bird struggle unsuccessfully to fly, yet display enough strength to evade rescuers, Robert J. Barham, head of the Louisiana Department of Wildlife and Fisheries, said, “It’s heart-rending—a blow to the pit of your stomach.”
An army of more than 20,000 people tried to hold back the dark tide, shoveling tar from beaches and laying down millions of feet of oil booms. They were fighting not just millions of gallons of oil but also long odds. The grim lesson from past spills: The techniques used to corral and skim up oil are mostly just “public relations,” says Robert Howarth, ecology professor at Cornell University and a veteran of the 1989 Exxon Valdez and other spills. “The physical methods almost always don’t work,” he says.
Doug Inkley, NWF senior scientist, calls an oil spill a Humpty Dumpty situation. “Once the oil is in the water, you are never going to recover even 10 percent of it.” Those odds will leave it mostly up to nature’s cleaning crew, microbes. By the second month of the spill, oxygen levels in the deep gulf were dropping—evidence that bacteria were already on the job, burning oxygen as they munched on oil. “The microbes have to save us again,” says University of Georgia marine scientist Samantha Joye, who was out at sea tracking the oil plumes. In the open water, bacteria are capable of consuming the oil in a few months. But in sediments and marshes, where oxygen is scarce or absent, the process slows dramatically. Forty years after a spill from the barge Florida off Cape Cod, and 21 years after Exxon Valdez, oil is still buried in mud and gravel.
The long life of spilled oil is one reason the eventual environmental and economic toll of the current disaster is hard to predict, scientists say. Complicating the assessment further, no previous spill took place in such deep water, and none involved the use of so many hundreds of thousands of gallons of toxic chemicals to disperse the oil. “Unfortunately, this will be the biggest experiment that we’ve ever had in oil-spill research,” says biologist Carys L. Mitchelmore of the University of Maryland Center for Environmental Science, whose own work shows that even small amounts of dispersant chemicals harm corals.
If there was one sliver of good news in this huge environmental and human tragedy, it was the effort mounted to save birds and other animals affected by the oil. In an industrial building turned wildlife rescue station in Fort Jackson, Louisiana, for example, workers clad in blue slickers and long yellow gloves sprayed a dilute solution of Dawn detergent on a brown pelican covered in oil. Using their hands, swabs and Q-tips, they delicately washed the bird from beak to toe. “It’s almost like shampooing your hair,” explained Jay Holcomb, executive director of the International Bird Rescue Research Center, which was working with Tri-State Bird Rescue and Research (under contract with the U.S. Fish and Wildlife Service) to save oiled animals. By mid-June, rescuers at four wildlife rehabilitation centers in the gulf had cleaned, nourished and released several dozen pelicans, northern gannets and herons.
Even this seemingly successful operation is not without controversy. “It’s a humanitarian effort that shouldn’t be confused with really making a difference to the birds and their populations,” warns Oregon ornithologist and biological consultant Brian Sharp, who helped determine the number of birds killed by the Exxon Valdez spill.
Consider the bleak track record. Biologist James Estes, of the University of California–Santa Cruz, calculated that each sea otter washed and released after Exxon Valdez cost $80,000—and two-thirds of them died within two years anyway; biologists estimate that natural annual mortality for the species is about 6 percent. An estimated 375,000 to 700,000 birds were killed by the Exxon Valdez spill, Sharp says, compared with 800 rescued (at a cost of $41 million)—and most of those died within days of being released. Cleaned and released birds should be counted among the dead, Sharp contended in the journal Ibis in 1996 and still believes today. That’s why, as harsh as it sounds, the standard practice in Germany and Norway has been euthanizing oiled birds and other wildlife.
In the United States, the public outcry over animal suffering made it impossible not to try to save oiled wildlife in Alaska and elsewhere. But based on the Exxon Valdez and other spills, many population biologists thought money spent on rescue work was money wasted. Far better to spend the cash on preserving habitats or helping endangered species, they said. Some ornithologists even tried to block the 1994 creation of an official response unit at the California Department of Fish and Game: the Oiled Wildlife Care Network. “Those were some of the ugliest days in science,” recalls wildlife biologist Richard T. Golightly of Humboldt State University.
In the years since, rescuers have blunted the criticism by getting better at what they do. The Oiled Wildlife Care Network, administered by the University of California–Davis (UCD), has built or helped outfit a dozen facilities capable of rehabilitating animals on a moment’s notice, caring for thousands of birds and other animals in more than 75 spills. Responding so quickly has been one key to better results, says Dave Jessup, director of California Fish and Game’s Marine Wildlife Veterinary Care and Research Center in Santa Cruz. Researchers also have improved their methods. “Our knowledge has grown exponentially,” says Michael Ziccardi, the veterinarian and UCD professor who heads the care network.
In California, for both birds and sea otters, the immediate threat created by a spill is the insidious effect of oil on their natural waterproofing. Normally, inner feathers or hair form an intricate interlocking structure that traps air next to the skin, keeping creatures dry and warm. Oil breaks up that structure. Suddenly, the animals can’t stay warm. They must eat more to rev up their metabolism. Unfortunately, the coating of oil makes it harder to float, fly, swim—or catch food. Then, as the creatures frantically preen and groom, they swallow and inhale oil. That ingestion can lead to pneumonia and organ damage. Death is usually swift and far from help. “The vast majority of animals that come in contact with oil are never even seen,” Estes says. Of the 584 affected birds found in the gulf by the end of May, 506 were already dead.
When oiled animals are lucky enough to be captured, the crucial task is quickly restoring their natural insulation. The actual washing, using Dawn detergent, hasn’t changed much sinceExxon Valdez in March 1989. But years of research on birds and on captive otters experimentally coated with canola oil have shown that the standard rinse with salt water leaves behind salt crystals and soap scum, disrupting the air layer. Rinsing with warm and softened freshwater works far better, scientists discovered. So does putting the cleaned animals into recovery tanks filled with softened freshwater. “We found we could cut the time from washing to full recovery in half,” Jessup says. His team had a chance to try the new methods for real on February 21, 2009, when a female sea otter coated in tar washed up in Monterey Bay. After her bath and freshwater rinse, she dined on abalone, prawns and clams for six weeks before growing strong enough to return to the wild (complete with a radio transmitter and a Facebook following). Jessup pegs the total cost for all her care at a bargain $5,000.
Similar improvements in care have been made for pelicans, common murres and other birds. And thanks to the battle against AIDS, rescuers have an arsenal of effective antifungal drugs to fight the infections that birds often develop in captivity. As a result, “the percentage of animals that survive to be released has increased dramatically,” the care network’s Ziccardi says. “Now, on average, it’s 50 to 70 percent.”
But do the released animals actually stay alive in the wild? Humboldt State’s Golightly was one of the skeptics. When an oil pipeline ruptured off the California coast in 1997, coating gulls and other birds with crude, Golightly figured it was a chance to answer the question. “Gulls are hardy,” he says. “If rehab didn’t work with them, then we didn’t need to waste time with any species.” Golightly outfitted released birds with radio transmitters. He also put captured non-oiled gulls through the cleaning process for a comparison. “I was frankly astounded,” he says. “Every one of the oiled birds survived as long as the radios lasted.” After he also got good results with common murres in a 1999 oil spill in Humboldt Bay and with surf scoters in 2007, Golightly became a believer in wildlife rescue—especially when populations are small and each individual animal matters. “I find myself converted to the notion that there is a significant effect on wildlife populations,” he says. Another benefit: “The data we collect will be part of evidence used to put a dollar value on the damage to the environment,” Ziccardi says.
Although rescuing even a handful of individuals belonging to an endangered species, such as the Kemp’s ridley sea turtle, can be critical to a population, successfully releasing a few rescued animals of any kind into the wild will not do much to make the gulf environment—and the region’s economy—whole again, scientists say. Even the pelicans and other birds lovingly cleaned of oil could be harmed by the long-term effects of oil and chemical dispersants, especially since animals could simply be exposed again in the wake of a massive spill such as the one in the gulf. Indeed, biologist Daniel Esler of the Centre for Wildlife Ecology at Simon Fraser University found that Alaskan harlequin ducks were still dying at a higher rate than normal from exposure to oil up to 14 years after Exxon Valdez. “The big lesson is that the oil persisted in the environment much longer than we expected,” he says.
Overall, the toll to gulf birds, turtles, sperm whales and other wildlife, along with the region’s $4-billion-per-year seafood industry and a whole way of life, is expected to be enormous. “It’s taken 20 years to figure out the effects of oil in Alaska,” Jessup says. “It could take longer with this spill.” One crucial question: How much of the coastal marshes can be protected from the oil?
Another danger of applauding wildlife rescue too much is that it diverts attention from the overall toll, Estes warns. “The thing I really object to is that the public is left with the impression that we are dealing with the problem,” he says. “We aren’t dealing with the problem.” NWF’s Inkley adds, “Focusing on birds and mammals, while it has its place, distracts from the larger trauma of habitat destruction as well as the harm, especially in the deep-water BP oil spill, to marine creatures living far beneath the water surface. We will likely never know the full toll for those species and can do nothing to rescue them.”
The real issue, of course, is that while fossil fuels have brought unprecedented global progress and wealth, they also are a deal with the devil. They cause everything from climate change and pollution to global political unrest. “I think this spill is one of the costs we pay for the life we live, if we want to utilize petroleum resources,” Estes says.
“The real solution is to work more diligently to reduce the risks of spills further,” Cornell’s Howarth says. Environmentalists hope, for instance, that this tragic spill will finally push the country—and the world—toward cleaner energy alternatives. As NWF president Larry Schweiger concluded during testimony before Congress in May, “We have a real opportunity to turn the corner on our destructive and decades-long dependence on oil.”
Virginia writer John Carey is a former senior correspondent for Business Week, who covered science and the environment.
http://www.nwf.org/News-and-Magazines/National-Wildlife/Animals/Archives/2010/Can-We-Rescue-Oiled-Wildlife.aspx
Christina Robev November 7/10
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