HOW MICROBES TEAMED TO CLEAN GULF

By Gautam Naik

The Wall Street Journal

By Gautam Naik | 892 words Associated Press A plume of oil is shown in May 2010 in the waters of Chandeleur Sound, La., in the wake of the explosion of the Deepwater Horizon offshore oil platform the previous month. A fortuitous combination of ravenous bacteria, ocean currents and local topography helped to rapidly purge the Gulf of Mexico of much of the oil and gas released in the Deepwater Horizon disaster of 2010, researchers reported .

After spewing oil and gas for nearly three months, the BP PLC well was finally capped in mid-July 2010. Some 200,000 tons of methane gas and about 4.4 million barrels of petroleum spilled into the ocean. Given the enormity of the spill, many scientists predicted that a significant amount of the resulting chemical pollutants would likely persist in the region's waterways for years.

According to a new federally funded study published Monday by the National Academy of Sciences, those scientists were wrong. By the end of September 2010, the vast underwater plume of methane, plus other gases, had all but disappeared. By the end of October, a significant amount of the underwater offshore oil—a complex substance made from thousands of compounds—had vanished as well.

"There was a lot of doomsday talk," said microbiologist David Valentine of the University of California, Santa Barbara, and co-author of the study, published in Proceedings of the National Academy of Sciences. But it turns out "the ocean harbors organisms that can handle a certain amount of input" in the form of oil and gas pollutants, he said. A year ago, Dr. Valentine and other scientists published a paper describing how bacteria that feed on naturally occurring oil and gas leaks underwater had apparently devoured much of the toxic chemicals released in the BP spill. That federally funded study, published in the journal Science, triggered disbelief among other researchers who questioned whether microbes could gobble up that much gas and oil so quickly.

Dr. Valentine and colleagues have now used a computer model to explain just how that scenario might have played out, though some scientists remain skeptical. It was an intricate challenge. The first step was to estimate the flow rate of the various hydrocarbons from the well over the 87 days that the spill continued. The researchers identified 26 classes of such chemicals; they then had to figure out which of these chemicals stayed in the deep plume that remained more than 3,000 feet underwater, and which ones rose up to the surface. For example, in the plume, certain chemicals dissolved completely in the water, including the methane gas, while some of the oil droplets were atomized and remained suspended in the water. A lot of the surface oil evaporated or washed up on Gulf shorelines.

Next, the scientists set about identifying the main species of oil-and-gas-eating bacteria that lived in the deep Gulf. They identified 52 main species of such microbes. The scientists also estimated how quickly the bacteria consumed oil and gas and how much the bacteria colonies grew. The final step was to model the complex movement of the water in the Gulf to determine where the oil and gas—and the bacteria—got transported.

Igor Mezic, a colleague of Dr. Valentine's and also a co-author, had published a study in 2011 predicting where the BP oil slick had spread. That analysis included data from the U.S. Navy's model of the Gulf's ocean currents and observations of the water's movements immediately after the spill and for several months after it ended. The UC Santa Barbara researchers decided to marry their two computer models—the one about the spill-eating bacteria with the one capturing the movement of water. When they ran the joint model, they found that it helped to explain the puzzle of the rapidly vanishing oil spill.

The model showed that the topography in the Gulf had played a vital role. Because the Gulf is bounded on three sides by land—north, east and west—the water currents don't flow in a single direction as in a river. Instead, the water sloshes around, back and forth, as if it were trapped in a washing machine. An initial population of bacteria encountered the spill near the BP well, its population grew, and then it was swept away by the ocean currents. But when the water circled back—that washing-machine effect—it was already loaded with these hungry bacteria, which immediately went on the attack again, mopping up another round of hydrocarbons. These repeated forays over the BP well, by the ever-growing bacterial populations, sped up the rate at which the methane and offshore oil got devoured.

Dr. Valentine suggested that oil companies ought to ascertain the currents, water motion and native microbial community in the water before embarking on any major offshore drilling project. "Then, if there is an event, we'd be many steps ahead of understanding where the oil may go and what the environment's response may be," he said.

Ira Leifer, a petroleum geochemist also at UC Santa Barbara who co-wrote a rebuttal to the 2011 paper published in Science, said the latest study was limited because it was based on a computer model "which is only as good as the input or assumptions" on which it is based. He noted, for example, that the authors had neglected to include a discussion of whether the bacteria would run out of critical nutrients necessary for them to consume the oil and gas and reproduce. The research was funded by the National Science Foundation, the Department of Energy and the Office of Naval Research.

ELEPHANTS THREATENED BY ILLEGAL IVORY TRADE

JOHANNESBURG — It's been a disastrous year for elephants, perhaps the worst since ivory sales were banned in 1989 to save the world's largest land animals from extinction, the wildlife trade monitoring network TRAFFIC said.

A record number of large seizures of elephant tusks represents at least 2,500 dead animals and shows that organized crime — in particular Asian syndicates — is increasingly involved in the illegal ivory trade and the poaching that feeds it, the group said.

Some of the seized tusks came from old stockpiles, the elephants having been killed years ago. It's not clear how many elephants were recently killed in Africa for their tusks, but experts are alarmed. TRAFFIC's elephant and rhino expert Tom Milliken thinks criminals may have the upper hand in the war to save rare and endangered animals. "As most large-scale ivory seizures fail to result in any arrests, I fear the criminals are winning," Milliken told The Associated Press.

Most cases involve ivory being smuggled from Africa into Asia, where growing wealth has fed the desire for ivory ornaments and for rhino horn that is used in traditional medicine, though scientists have proved it has no medicinal value. "The escalation in ivory trade and elephant and rhino killing is being driven by the Asian syndicates that are now firmly enmeshed within African societies," Milliken said in a telephone interview from his base in Zimbabwe. "There are more Asians than ever before in the history of the continent, and this is one of the repercussions."

All statistics are not yet in, and no one can say how much ivory is getting through undetected, but "what is clear is the dramatic increase in the number of large-scale seizures, over 800 kilograms (1,760 pounds) in weight, that have taken place in 2011," TRAFFIC said in a statement. There were at least 13 large seizures this year, compared to six in 2010 with a total weight just under 1,000 kilograms (2,200 pounds). In the most recent, and worst, case Malaysian authorities seized hundreds of African elephant tusks on Dec. 21 worth $1.3 million that were being shipped to Cambodia. The ivory was hidden in containers of handicrafts from Kenya's Mombasa port. Most large seizures have originated from Kenyan or Tanzanian ports, TRAFFIC said.

Fifty elephants a month are being killed, their tusks hacked off, in Tanzania's Selous Game Reserve, according to the Washington-based Environmental Investigation Agency. With shipments so large, criminals have taken to shipping them by sea instead of by air, falsifying documents with help of corrupt officials, monitors said. Milliken said some of the seized ivory has been identified as coming from government-owned stockpiles — made up of confiscated tusks and those of dead elephants — in another sign of corruption.

"In 23 years of compiling ivory seizure data ... this is the worst year ever for large ivory seizures. 2011 has truly been a horrible year for elephants," said Milliken. Rhinos also have suffered. A record 443 rhino were killed in this year in South Africa, compared to 333 last year, according to National Geographic News Watch. South Africa is home to 90 percent of the rhinos left on the continent.

Africa's elephant population was estimated at between 5 million and 10 million before the big white hunters came to the continent with European colonization. Massive poaching for the ivory trade in the 1980s halved the remaining number of African elephants to about 600,000. Following the 1989 ban on ivory trade and concerted international efforts to protect the animals, elephant herds in east and southern Africa were thriving before the new threat arrived from Asia. A report from Kenya's Amboseli national park highlighted the dangers. There had been almost no poaching in the park, which lies in the shadow of Mount Kilimanjaro, for 30 years until a Chinese company was awarded the contract to build a highway nearby two years ago. Amboseli has lost at least four of its "big tuskers" since then.

BOGUS MEDICAL CLAIMS FOR RHINO HORN THREATENS SPECIES

JOHANNESBURG — A record number of rhinos were poached this year in South Africa, home to the greatest number of the animals, as rising demand in Asia for their horns led to increased killings of the threatened species.

At least 443 rhinos have been killed in South Africa in 2011, up from 333 last year, according to National Geographic News Watch. The street value of rhinoceros horns has soared to about $65,000 a kilogram (2.2 pounds), making it more expensive than gold, platinum and in many cases cocaine, as a belief — with no basis in science — has taken hold in recent years in parts of Asia that ingesting it can cure or prevent cancer.

South Africa, home to more than 20,000 rhinos, was losing about 15 animals a year a decade ago. But poaching increased dramatically from about 2007 as a growing affluent class in places such as Vietnam and Thailand began spending more on rhino horn for traditional medicine.

The number of rhinoceroses dying unnatural deaths in South Africa, either through illegal poaching or legal hunts, has reached a level likely to lead to population decline, according to a study by Richard Emslie, an expert in the field. About half of poaching takes place in Kruger National Park, the country's flagship park covering an area about the size of Israel, where soldiers and surveillance aircraft have been deployed in recent months to slow the carnage.

The park has been the focal point of an arms race as gangs of poachers sponsored by international crime syndicates have used high-powered weaponry, night vision goggles and helicopters to hunt the animals, investigators said. South Africa, home to over 90 percent of the rhinos in Africa, grants licenses for legal hunts, with a growing number of the horns then mounted as trophies, shipped to Asia and sold on the black market, according to police and customs officials. Many poachers were trained by Mozambique's military or police and are now living in squalor in the border region next to Kruger, South African investigators said. Their cut of the rhino money is relatively small compared to other players in the international trade but is considered a fortune at home.

Rhino horn has been used for centuries in Chinese medicine, where it was ground into a powder and often mixed with hot water to treat a variety of maladies including rheumatism, gout, high fever and even devil possession. In recent years, it has also taken on a reputation for being an aphrodisiac and cancer cure.

"Nothing is more tragic than to see this totally unnecessary and brutal killing of an animal for its horn, and the horn in turn has zero medicinal value," said Pelham Jones, a leader of the South Africa Private Rhino Owners Association. Campaigners in South Africa are urging President Jacob Zuma to uphold a 1993 treaty on international trade in endangered species and to engage with China, Vietnam and Thailand with a view to ending the trade in rhino horn and other animal parts. In September the country's Department of Water and Environmental Affairs signed a memorandum of understanding with Vietnam which it hoped would lead to an agreement to help curb rhino poaching in South Africa. The department is seeking similar agreements with Thailand and China.

BIRDS' SOURCE OF WATER UNCOVERED

Los Angeles Times

LOS ANGELES -- Twice a year, bar-tailed godwits migrate more than 7,000 miles so they can spend their summers in Alaska and their winters in New Zealand. Bar-headed geese fly about 2,000 miles between Mongolia and India.

Such flights are physically draining, requiring birds to expend enormous amounts of energy without stopping for food or water. For years, scientists have wondered how they do it.

Now researchers think they've figured out how birds stay hydrated on their marathon journeys.

Observing tiny songbirds, biologists at the University of Western Ontario in Canada discovered the animals conserve water by burning muscle and organs instead of fat. The protein in muscle doesn't provide as much energy as fat, but it can release five times as much water, according to a study published Friday in the journal Science.

The idea that birds get water from their own muscles and organs isn't entirely new, but until recently scientists haven't had a way to test the theory, said Marcel Klaassen, an integrative ecologist at Deakin University in Australia who was among the early proponents of the idea.

That changed in 2009, with the. completion of the world's most advanced avian wind tunnel at the University of Western Ontario. It resembles a "giant steel doughnut" 150 feet long and two stories high, said study leader Alexander Gerson, a graduate student in biology.

In addition, scientists can now measure the amount of fat, protein and water in birds' bodies using a noninvasive technique called quantitative magnetic resonance analysis. The songbirds used in the study were Swainson's thrushes. They breed in northern Canada and spend their winters in South America, migrating twice a year. For their experiment, biologists captured thrushes on the north shore of Lake Erie, Gerson said. They analyzed the body composition of each bird in the QMR device before putting the animals into the wind tunnel, letting them fly for an average of about 2 1/2 hours, and then measuring body composition again at the end of the flight.

It wasn't easy to get birds to cooperate. Scientists tried to test 27 thrushes but were able to collect sufficient data on only five.

But the results gathered from the compliant birds demonstrated uniformly that the thrushes were burning muscle and organs to get water, Gerson said. No birds became dehydrated, and all burned significantly more protein tissue under dry conditions than under wet conditlons.

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