OREGON STATE UNIVERSITY

scientific research and advances

Review: Lead ammunition can be deadly, though mitigation may help

CORVALLIS, Ore. – The ingestion of lead ammunition and lead fishing tackle accounts for illness and mortality in more than 120 different species of birds in North America, according to a newly published review of scientific studies on the issue.

What impact that has at the population level for species is less clear, the researchers say, as is how to deal with the growing controversy over the use of lead for hunting and fishing. The lead issue is complex and steps to mitigate the impacts will be challenging – from cost and performance factors to manufacturing output – but they are possible, the authors point out.

“Although lead shot has been banned for waterfowl hunting in the United States since 1991, and in Canada since 1999, exposure to lead remains a problem for many bird species,” said Susan Haig, supervisory wildlife ecologist with the U.S. Geological Survey and lead author on the study. “However, we did find several examples of ways wildlife managers have helped reduce exposure of birds to lead.”

The review of scientific studies, conducted by biologists from several different institutions and agencies, was published in the July edition of the journal The Condor: Ornithological Applications. A companion perspective article, written by Clinton Epps, an associate professor in the Department of Fisheries and Wildlife at Oregon State University, examines the challenges of transitioning to non-lead ammunition.

In their papers, the researchers do not call for any policy changes, but they outline some of the challenges of reducing the use of lead and explore tactics that have been used to reduce lead exposure.

“Shifting to non-lead alternatives is a lot more complicated than some people think,” said Epps, who has hunted for more than 30 years. “Any efforts to shift hunters and fishermen from using lead needs to be well-informed and collaborative. Everyone concerned with this issue must be prepared to invest time, money, and expertise to work not only with hunters and fishermen, but with ammunition and tackle manufacturers.”

Epps has looked at copper bullets as one less-toxic alternative to lead and notes that they generally work well in modern firearms commonly used for big game hunting. However, effective non-lead alternatives have not yet been developed for all types of hunting firearms, he added.

In the review article, the researchers outline the availability of non-lead ammunition in October 2013 in 35 different calibers and 51 rifle-cartridge configurations at three major online retailers. Of the non-lead options sold by those retailers, only a small proportion was actually in stock: Cabela’s had non-lead ammunition in 18 percent of available sizes; Cheaper Than Dirt, 27 percent; and Bass Pro Shops, 10 percent.

“Non-lead bullets can be difficult to find in all calibers needed, but availability is improving,” Epps said. “Premium quality hunting ammunition costs about the same for lead-based and non-lead options, but I see a lot of people using the cheaper options, which invariably contain lead, so cost may be an issue – particularly for high-volume users.”

The physical properties of lead – including high density, low melting point, malleability and resistance to corrosion – have made it popular in the manufacturing of ammunition and fishing sinkers. However, many birds are sensitive to lead exposure, affecting the structure and function of kidneys, bones, the central nervous system and the blood system. Impacts range from lethargy and anorexia, to reproductive issues and death.

In their review, the researchers noted that lead has widely varying impacts.

  • One study of common loon carcasses found across six New England states found that about 23 percent (118 of 522) of the deaths were caused by ingestion of lead fishing tackle and ammunition;
  • California condors are extremely susceptible to lead poisoning and suffer significant mortality, yet a related species known as turkey vultures can survive with greater and longer exposure to lead;
  • Few studies have been done on population-level impacts of lead with the most complete studies conducted on waterfowl, where deaths from lead poisoning are estimated to be 2-3 percent overall, and 4 percent in mallard ducks.

A survey by the U.S. Geological Survey in 2013 found that 69,000 metric tons (a metric ton is about 2,204 pounds) of lead were used in the production of ammunition in the United States in one year. Annual estimates of lead fishing weights sold in the U.S. equal 3,977 metric tons.

Birds and other animals ingest lead in different ways, according to Haig. Loons, for example, were found to have swallowed lead sinkers and jigs, perhaps mistaking them for prey. Scavengers including condors and eagles often feed on carcasses of animals killed by hunters and cannot avoid incidental lead ingestion.

“Some birds use lead pellets or fragments as grit to aid in digestion after consuming it at hunting areas or shooting ranges,” said Haig, who is a courtesy professor of wildlife ecology at OSU. “Another potentially important lead source is recreational shooting of ground squirrels, which leaves lead-laced carcasses available to be eaten by golden eagles, Swainson’s hawks and other birds of prey.

“We found one estimate that more than 1.1 million ground squirrels were shot in one state during a one-year period,” she added. “It would be helpful to better understand what kinds of risk this poses to raptor scavengers.”

The review outlines some steps to reduce lead exposure to birds, including redistributing shot in the surface soil by cultivating sediments; raising water levels in wetlands to reduce access by feeding birds; and providing alternative uncontaminated food sources.

“Managers have found a number of ways to reduce the risk of lead exposure to birds while preserving the important role hunting plays in wildlife conservation,” Haig said.

One example cited involved Arizona Game and Fish working with other groups in that state on a voluntary approach to the issue.

“They formed a coalition to educate hunters about the negative effects of lead,” Haig pointed out. “The result was more than 80 percent compliance with voluntary non-lead ammunition use among hunters on the Kaibab Plateau and no birds were found with lead poisoning the following year.”

Other authors on the review include Jesse D’Elia, U.S. Fish and Wildlife Service and OSU Department of Fisheries and Wildlife; Collin Eagles-Smith, U.S. Geological Survey and OSU Fisheries and Wildlife; Garth Herring, U.S. Geological Survey; Jeanne M. Fair, Los Alamos National Laboratory; Jennifer Gervais, Oregon Wildlife Institute and OSU Fisheries and Wildlife; James W. Rivers, OSU Department of Forest Ecosystems and Society; and John H. Schulz, University of Missouri.

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Susan Haig, 541-750-0981, susan_haig@usgs.gov; Clint Epps, 541-737-2478, Clinton.epps@oregonstate.edu

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Figure 2 Magpie on carcass
magpie feedng on a carcass

SAR11, oceans’ most abundant organism, has ability to create methane

CORVALLIS, Ore. – The oxygen-rich surface waters of the world’s major oceans are supersaturated with methane – a powerful greenhouse gas that is roughly 20 times more potent than carbon dioxide – yet little is known about the source of this methane.

Now a new study by researchers at Oregon State University demonstrates the ability of some strains of the oceans’ most abundant organism – SAR11 – to generate methane as a byproduct of breaking down a compound for its phosphorus.

Results of the study are being published this week in Nature Communications. It was funded by the National Science Foundation and the Gordon and Betty Moore Foundation.

“Anaerobic methane biogenesis was the only process known to produce methane in the oceans and that requires environments with very low levels of oxygen,” said Angelicque “Angel” White, a researcher in OSU’s College of Earth, Ocean, and Atmospheric Sciences and co-author on the study. “In the vast central gyres of the Pacific and Atlantic oceans, the surface waters have lots of oxygen from mixing with the atmosphere – and yet they also have lots of methane, hence the term ‘marine methane paradox.’

“We’ve now learned that certain strains of SAR11, when starved for phosphorus, turn to a compound known as methylphosphonic acid,” White added. “The organisms produce enzymes that can break this compound apart, freeing up phosphorus that can be used for growth – and leaving methane behind.”

The discovery is an important piece of the puzzle in understanding the Earth’s methane cycle, scientists say. It builds on a series of studies conducted by researchers from several institutions around the world over the past several years.

Previous research has shown that adding methylphosphonic acid, or MPn, to seawater produces methane, though no one knew exactly how. Then a laboratory study led by David Karl of the University of Hawaii and OSU’s White found that an organism called Trichodesmium could break down MPn and thus it could be a potential source of phosphorus, which is a critical mineral essential to every living organism.

However, Trichodesmium are rare in the marine environment and unlikely to be the only source for vast methane deposits in the surface waters.

So White turned to Steve Giovannoni, a distinguished professor of microbiology at OSU, who not only maintains the world’s largest bank of SAR11 strains, but who also discovered and identified SAR11 in 1990. In a series of experiments, White, Giovannoni, and graduate students Paul Carini and Emily Campbell tested the capacity of different SAR11 strains to consume MPn and cleave off methane.

“We found that some did produce a methane byproduct, and some didn’t,” White said. “Just as some humans have a different capacity for breaking down compounds for nutrition than others, so do these organisms. The bottom line is that this shows phosphate-starved bacterioplankton have the capability of producing methane and doing so in oxygen-rich waters.”

SAR11 is the smallest free-living cell known and also has the smallest genome, or genetic structure, of any independent cell. Yet it dominates life in the oceans, thrives where most other cells would die, and plays a huge role in the cycling of carbon on Earth.

These bacteria are so dominant that their combined weight exceeds that of all the fish in the world's oceans, scientists say. In a marine environment that's low in nutrients and other resources, they are able to survive and replicate in extraordinary numbers – a milliliter of seawater, for instance, might contain 500,000 of these cells.

"The ocean is a competitive environment and these bacteria apparently won the race," said Giovannoni, a professor in OSU’s College of Science. "Our analysis of the SAR11 genome indicates that they became the dominant life form in the oceans largely by being the simplest.”

“Their ability to cleave off methane is an interesting finding because it provides a partial explanation for why methane is so abundant in the high-oxygen waters of the mid-ocean regions,” Giovannoni added. “Just how much they contribute to the methane budget still needs to be determined.”

Since the discovery of SAR11, scientists have been interested in their role in the Earth’s carbon budget. Now their possible implication in methane creation gives the study of these bacteria new importance.

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Angel White, 541-737-6397; awhite@coas.oregonstate.edu; Steve Giovannoni, 541-737-1835, steve.giovannoni@oregonstate.edu

Video games could provide venue for exploring sustainability concepts

CORVALLIS, Ore. – Could playing video games help people understand and address global sustainability issues such as pollution, drought or climate change? At least two researchers believe so, outlining their argument in a concept paper published in the journal “First Monday.”

Video games have the potential to educate the public and encourage development of creative solutions to social, economic and environmental problems, said Oregon State University’s Shawna Kelly, one of the two authors of the article.

“Video games encourage creative and strategic thinking, which could help people make sense of complex problems,” said Kelly, who teaches new media communications in the School of Arts and Communication at Oregon State’s College of Liberal Arts.

“Entertainment has always been a space for exposing people to new ideas. Using video games, it’s possible to introduce sustainability concepts to the mass public in a way that’s not pedantic, that’s not educational,” Kelly said. “Instead, it could be fun and it could be challenging.”

Kelly wrote the paper with Bonnie Nardi, an anthropologist with University of California, Irvine's Department of Informatics, who studies sustainability, collapse-preparedness and information technology. 

Kelly and Nardi identified four key areas in which video games could support sustainable practices. The areas are:

  • Shift away from growth as the end goal of a game. Uncontrollable growth is unsustainable and asks little of players’ imaginations.
  • Emphasize scavenging instead of combat to collect resources. Encourage players to interact with their environment in creative ways instead of simply looking for targets.
  • Offer complex avenues for social interaction. Move beyond “us versus them” and focus on other types of social collaborations.
  • Encourage strategizing with resources such as scenarios that incorporate long-term consequences and interdependencies of resource use.

Some video games already are using some of the elements Kelly and Nardi recommend. Economics-based games such as “EVE Online” challenge players to strategize between their short-term personal resource demands and the long-term needs of a larger group of players, their corporation. “DayZ” is a combat simulation game that requires players to scavenge for resources and work with other players, deciding on their own which players are friends and which are enemies.

Those are the kinds of game mechanics that make video games fun and challenging, but those mechanics also could be used to encourage players to think about real problems related to sustainability, Kelly said.

The culture of video gaming rewards people for solving problems and coming up with unique solutions. There is a common interest and connection among players, and knowledge is easily shared via game-specific wikis, message boards, instant messaging and more, Kelly pointed out.

“There’s a huge set of people out there who love to problem-solve,” she said. “Why not harness that power that is already there?”

That doesn’t mean someone should go out and develop “The Sustainability Game,” Kelly said. While video games have proven to be a good educational tool, there is a sense that those who play video games for entertainment don’t want forced educational components, she said.

“The attitude is ‘don’t make me learn something,’ ” Kelly said. “Instead, make the problems accessible to the gaming community and see what emerges.”

Kelly plans to continue exploring the relationship between video games and sustainability through additional research supported by OSU’s New Media Communications department. She’s planning to conduct a systematic survey of the use of sustainability concepts in current video games during the 2014-15 school year using undergraduate student research assistants and resources from New Media Communications.

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“Molecular movie” technology may enable big gains in bioimaging, health research

CORVALLIS, Ore. – Researchers today announced the creation of an imaging technology more powerful than anything that has existed before, and is fast enough to observe life processes as they actually happen at the molecular level.

Chemical and biological actions can now be measured as they are occurring or, in old-fashioned movie parlance, one frame at a time. This will allow creation of improved biosensors to study everything from nerve impulses to cancer metastasis as it occurs.

The measurements, created by the use of short pulse lasers and bioluminescent proteins, are made in femtoseconds, which is one-millionth of one-billionth of a second. A femtosecond, compared to one second, is about the same as one second compared to 32 million years.

That’s a pretty fast shutter speed, and it should change the way biological research and physical chemistry are being done, scientists say.

Findings on the new technology were published today in Proceedings of the National Academy of Sciences, by researchers from Oregon State University and the University of Alberta.

“With this technology we’re going to be able to slow down the observation of living processes and understand the exact sequences of biochemical reactions,” said Chong Fang, an assistant professor of chemistry in the OSU College of Science, and lead author on the research.

“We believe this is the first time ever that you can really see chemistry in action inside a biosensor,” he said. “This is a much more powerful tool to study, understand and tune biological processes.”

The system uses advanced pulse laser technology that is fairly new and builds upon the use of “green fluorescent proteins” that are popular in bioimaging and biomedicine. These remarkable proteins glow when light is shined upon them. Their discovery in 1962, and the applications that followed, were the basis for a Nobel Prize in 2008.

Existing biosensor systems, however, are created largely by random chance or trial and error. By comparison, the speed of the new approach will allow scientists to “see” what is happening at the molecular level and create whatever kind of sensor they want by rational design. This will improve the study of everything from cell metabolism to nerve impulses, how a flu virus infects a person, or how a malignant tumor spreads.

“For decades, to create the sensors we have now, people have been largely shooting in the dark,” Fang said. “This is a fundamental breakthrough in how to create biosensors for medical research from the bottom up. It’s like daylight has finally come.”

The technology, for instance, can follow the proton transfer associated with the movement of calcium ions – one of the most basic aspects of almost all living systems, and also one of the fastest. This movement of protons is integral to everything from respiration to cell metabolism and even plant photosynthesis.  Scientists will now be able to identify what is going on, one step at a time, and then use that knowledge to create customized biosensors for improved imaging of life processes.

“If you think of this in photographic terms,” Fang said, “we now have a camera fast enough to capture the molecular dance of life. We’re making molecular movies. And with this, we’re going to be able to create sensors that answer some important, new questions in biophysics, biochemistry, materials science and biomedical problems.”

The research was supported by OSU, the University of Alberta, the Natural Sciences and Engineering Research Council of Canada, and the Canadian Institutes of Health Research.

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Chong Fang, 541-737-6704

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Molecular movies

Molecular movies

NSF awards $200,000 to develop technology to treat sepsis, a global killer

CORVALLIS, Ore. – The National Science Foundation has just awarded $200,000 to engineers at Oregon State University who have developed a new technology that they believe could revolutionize the treatment and prevention of sepsis.

Sepsis is a “hidden killer” that in the United States actually kills more people every year than AIDS, prostate cancer and breast cancer combined.

More commonly called “blood poisoning,” sepsis can quickly turn a modest infection into a whole-body inflammation, based on a dysfunctional immune response to endotoxins that are released from the cell walls of bacteria. When severe, this can lead to multiple organ failure and death.

When treatment is begun early enough, sepsis can sometimes be successfully treated with antibiotics. But they are not always effective and the mortality rate for the condition is still 28-50 percent. About one in every four people in a hospital emergency room is there because of sepsis, and millions of people die from it around the world every year, according to reports in the New England Journal of Medicine and other studies.

In pioneering research, OSU experts have used microchannel technology and special coatings to create a small device through which blood could be processed, removing the problematic endotoxins and preventing sepsis. Several recent professional publications have reported on their progress.

“More work remains to be done, and the support from the National Science Foundation will be instrumental in that,” said Adam Higgins, principal investigator on the grant and an assistant professor in the OSU School of Chemical, Biological and Environmental Engineering. “When complete, we believe this technology will treat sepsis effectively at low cost, or even prevent it when used as a prophylactic treatment.”

This technology may finally offer a way to tackle sepsis other than antibiotics, the researchers said.

“This doesn’t just kill bacteria and leave floating fragments behind, it sticks to and removes the circulating bacteria and endotoxin particles that might help trigger a sepsis reaction,” said Karl Schilke, the OSU Callahan Faculty Scholar in Chemical Engineering.

“We hope to emboss the device out of low-cost polymers, so it should be inexpensive enough that it can be used once and then discarded,” Schilke said. “The low cost would also allow treatment even before sepsis is apparent. Anytime there’s a concern about sepsis developing – due to an injury, a wound, an operation, or an infection – you could get ahead of the problem.”

“A big part of the problem with sepsis is that it moves so rapidly,” said Joe McGuire, professor and head of the OSU Department of Chemical, Biological and Environmental Engineering. “By the time it’s apparent what the problem is, it’s often too late to treat it.

“If given early enough, antibiotics and other treatments can sometimes, but not always, stop this process,” McGuire said. “Once these bacterial fragments are in the blood stream the antibiotics won’t always work. You can have successfully eradicated the living bacteria even as you’re dying.”

The approach being developed at the OSU College of Engineering is to move blood through a very small processor, about the size of a coffee mug, and literally grab the endotoxins and remove them.

Microchannels make this possible. They can provide accelerated heat and mass transfer as fluids move through tiny tubes the width of a human hair. Applications are already being studied in everything from heat exchangers to solar energy. They can be produced in mass quantity at low cost, stamped onto a range of metals or plastics, and used to process a large volume of liquid in a comparatively short time.

In the system developed at Oregon State, blood can be pumped through thousands of microchannels that are coated with what researchers call “pendant polymer brushes,” with repeating chains of carbon and oxygen atoms anchored on the surface. This helps prevent blood proteins and cells from sticking or coagulating. On the end of each pendant chain is a peptide – or bioactive agent – that binds tightly to the endotoxin and removes it from the blood, which then goes directly back to the patient.

Sepsis is fairly common. It can develop after an injury from an automobile accident, a dirty wound, an extended operation in a hospital that carries a risk of infection, or infectious illnesses in people with weak or compromised immune systems.

In the U.S., more than $20 billion was spent on this problem in 2011. It’s the single most expensive cause of health problems that require hospitalization.

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Adam Higgins, 541-737-6245

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Sepsis device

Sepsis device

Study links Greenland ice sheet collapse, sea level rise 400,000 years ago

CORVALLIS, Ore. – A new study suggests that a warming period more than 400,000 years ago pushed the Greenland ice sheet past its stability threshold, resulting in a nearly complete deglaciation of southern Greenland and raising global sea levels some 4-6 meters.

The study is one of the first to zero in on how the vast Greenland ice sheet responded to warmer temperatures during that period, which were caused by changes in the Earth’s orbit around the sun.

Results of the study, which was funded by the National Science Foundation, are being published this week in the journal Nature.

“The climate 400,000 years ago was not that much different than what we see today, or at least what is predicted for the end of the century,” said Anders Carlson, an associate professor at Oregon State University and co-author on the study. “The forcing was different, but what is important is that the region crossed the threshold allowing the southern portion of the ice sheet to all but disappear.

“This may give us a better sense of what may happen in the future as temperatures continue rising,” Carlson added.

Few reliable models and little proxy data exist to document the extent of the Greenland ice sheet loss during a period known as the Marine Isotope Stage 11. This was an exceptionally long warm period between ice ages that resulted in a global sea level rise of about 6-13 meters above present. However, scientists have been unsure of how much sea level rise could be attributed to Greenland, and how much may have resulted from the melting of Antarctic ice sheets or other causes.

To find the answer, the researchers examined sediment cores collected off the coast of Greenland from what is called the Eirik Drift. During several years of research, they sampled the chemistry of the glacial stream sediment on the island and discovered that different parts of Greenland have unique chemical features. During the presence of ice sheets, the sediments are scraped off and carried into the water where they are deposited in the Eirik Drift.

“Each terrain has a distinct fingerprint,” Carlson noted. “They also have different tectonic histories and so changes between the terrains allow us to predict how old the sediments are, as well as where they came from. The sediments are only deposited when there is significant ice to erode the terrain. The absence of terrestrial deposits in the sediment suggests the absence of ice.

“Not only can we estimate how much ice there was,” he added, “but the isotopic signature can tell us where ice was present, or from where it was missing.”

This first “ice sheet tracer” utilizes strontium, lead and neodymium isotopes to track the terrestrial chemistry.

The researchers’ analysis of the scope of the ice loss suggests that deglaciation in southern Greenland 400,000 years ago would have accounted for at least four meters – and possibly up to six meters – of global sea level rise. Other studies have shown, however, that sea levels during that period were at least six meters above present, and may have been as much as 13 meters higher.

Carlson said the ice sheet loss likely went beyond the southern edges of Greenland, though not all the way to the center, which has not been ice-free for at least one million years.

In their Nature article, the researchers contrasted the events of Marine Isotope Stage 11 with another warming period that occurred about 125,000 years ago and resulted in a sea level rise of 5-10 meters. Their analysis of the sediment record suggests that not as much of the Greenland ice sheet was lost – in fact, only enough to contribute to a sea level rise of less than 2.5 meters.

“However, other studies have shown that Antarctica may have been unstable at the time and melting there may have made up the difference,” Carlson pointed out.

The researchers say the discovery of an ice sheet tracer that can be documented through sediment core analysis is a major step to understanding the history of ice sheets in Greenland – and their impact on global climate and sea level changes. They acknowledge the need for more widespread coring data and temperature reconstructions.

“This is the first step toward more complete knowledge of the ice history,” Carlson said, “but it is an important one.”

Lead author on the Nature study is Alberto Reyes, who worked as a postdoctoral researcher for Carlson when both were at the University of Wisconsin-Madison. Carlson is now on the faculty in Oregon State’s College of Earth, Ocean, and Atmospheric Sciences.

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Anders Carlson, 541-737-3625; acarlson@coas.oregonstate.edu

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backpacks

Discovery of a bud-break gene could lead to trees adapted for a changing climate

CORVALLIS, Ore. — Scientists have confirmed the function of a gene that controls the awakening of trees from winter dormancy, a critical factor in their ability to adjust to environmental changes associated with climate change.

While other researchers have identified genes involved in producing the first green leaves of spring, the discovery of a master regulator in poplar trees (Populus species) could eventually lead to breeding plants that are better adapted for warmer climates.

The results of the study that began more than a decade ago at Oregon State University were published today in the Proceedings of the National Academy of Sciences, by scientists from Michigan Technological University and Oregon State.

“No one has ever isolated a controlling gene for this timing in a wild plant, outside of Arabidopsis, a small flowering plant related to mustard and cabbage,” said Steve Strauss, co-author and distinguished professor of forest biotechnology at OSU. “This is the first time a gene that controls the timing of bud break in trees has been identified.”

The timings of annual cycles — when trees open their leaves, when they produce flowers, when they go dormant — help trees adapt to changes in environmental signals like those associated with climate, but the genetics have to keep up, Strauss said.

While trees possess the genetic diversity to adjust to current conditions, climate models suggest that temperature and precipitation patterns in many parts of the world may expose trees to more stressful conditions in the future. Experts have suggested that some tree species may not be able to cope with these changes fast enough, whether by adaptation or migration. As a result, forest health may decline, trees may disappear from places they are currently found, and some species may even go extinct. 

“For example, are there going to be healthy and widespread populations of Douglas fir in Oregon in a hundred years?” said Strauss. “That depends on the natural diversity that we have and how much the environment changes. Will there be sufficient genetic diversity around to evolve populations that can cope with a much warmer and likely drier climate? We just don’t know.”

Strauss called the confirmation of the bud-break gene — which scientists named EBB1 for short — a “first step” in developing the ability to engineer adaptability into trees in the future.

“Having this knowledge enables you to engineer changes when they might become urgent,” he said.

Yordan Yordanov and Victor Busov at Michigan Tech worked with Cathleen Ma and Strauss at Oregon State to trace the function of EBB1 in buds and other plant tissues responsible for setting forth the first green shoots of spring. They developed modified trees that overproduced EBB1 genes and emerged from dormancy earlier in the year. They also showed that trees with less EBB1 activity emerged from dormancy later.

“The absence of EBB1 during dormancy allows the tree to progress through the physiological, developmental and adaptive changes leading to dormancy,” said Busov, “while the expression of EBB1 in specific cell layers prior to bud-break enables reactivation of growth in the cells that develop into shoots and leaves, and re-entry into the active growth phase of the tree.”

The study began when Strauss noticed poplar trees emerging earlier than others in an experimental field trial at Oregon State. One April morning, he found that four seedling trees in a 2.5-acre test plot were putting forth leaves at least a week before all the other trees. Strauss and Busov, a former post-doctoral researcher at Oregon State, led efforts to identify the genes responsible.

They found that EBB1 codes for a protein that helps to restart cell division in a part of the tree known as meristem, which is analogous to stem cells in animals. EBB1 also plays a role in suppressing genes that prepare trees for dormancy in the fall and in other processes such as nutrient cycling and root growth that are critical for survival. Altogether, they found nearly 1,000 other poplar genes whose activity is affected by EBB1.

It’s unlikely that plant breeders will use the finding any time soon, Strauss said. Breeders tend to rely on large clusters of genes that are associated with specific traits such as hardiness, tree shape or flowering. However, as more genes of this kind are identified, the opportunity to breed or engineer trees adapted to extreme conditions will grow.

Funding for the research was provided by the U.S. Department of Agriculture, the U.S. Department of Energy and the Tree Biosafety and Genomics Research Cooperative at Oregon State.

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Steve Strauss, 541-737-6578

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Bud break

Tree research


Early flush

Early leaf flush

Findings point toward one of first therapies for Lou Gehrig’s disease

CORVALLIS, Ore. – Researchers have determined that a copper compound known for decades may form the basis for a therapy for amyotrophic lateral sclerosis (ALS), or Lou Gehrig’s disease.

In a new study just published in the Journal of Neuroscience, scientists from Australia, the United States (Oregon), and the United Kingdom showed in laboratory animal tests that oral intake of this compound significantly extended the lifespan and improved the locomotor function of transgenic mice that are genetically engineered to develop this debilitating and terminal disease.

In humans, no therapy for ALS has ever been discovered that could extend lifespan more than a few additional months. Researchers in the Linus Pauling Institute at Oregon State University say this approach has the potential to change that, and may have value against Parkinson’s disease as well.

“We believe that with further improvements, and following necessary human clinical trials for safety and efficacy, this could provide a valuable new therapy for ALS and perhaps Parkinson’s disease,” said Joseph Beckman, a distinguished professor of biochemistry and biophysics in the OSU College of Science.

“I’m very optimistic,” said Beckman, who received the 2012 Discovery Award from the OHSU Medical Research Foundation as the leading medical researcher in Oregon.

ALS was first identified as a progressive and fatal neurodegenerative disease in the late 1800s and gained international recognition in 1939 when it was diagnosed in American baseball legend Lou Gehrig. It’s known to be caused by motor neurons in the spinal cord deteriorating and dying, and has been traced to mutations in copper, zinc superoxide dismutase, or SOD1. Ordinarily, superoxide dismutase is an antioxidant whose proper function is essential to life.

When SOD1 is lacking its metal co-factors, it “unfolds” and becomes toxic, leading to the death of motor neurons. The metals copper and zinc are important in stabilizing this protein, and can help it remain folded more than 200 years.

“The damage from ALS is happening primarily in the spinal cord and that’s also one of the most difficult places in the body to absorb copper,” Beckman said. “Copper itself is necessary but can be toxic, so its levels are tightly controlled in the body. The therapy we’re working toward delivers copper selectively into the cells in the spinal cord that actually need it. Otherwise, the compound keeps copper inert.”

“This is a safe way to deliver a micronutrient like copper exactly where it is needed,” Beckman said.

By restoring a proper balance of copper into the brain and spinal cord, scientists believe they are stabilizing the superoxide dismutase in its mature form, while improving the function of mitochondria. This has already extended the lifespan of affected mice by 26 percent, and with continued research the scientists hope to achieve even more extension.

The compound that does this is called copper (ATSM), has been studied for use in some cancer treatments, and is relatively inexpensive to produce.

“In this case, the result was just the opposite of what one might have expected,” said Blaine Roberts, lead author on the study and a research fellow at the University of Melbourne, who received his doctorate at OSU working with Beckman.

“The treatment increased the amount of mutant SOD, and by accepted dogma this means the animals should get worse,” he said. “But in this case, they got a lot better. This is because we’re making a targeted delivery of copper just to the cells that need it.

“This study opens up a previously neglected avenue for new disease therapies, for ALS and other neurodegenerative disease,” Roberts said.

Other collaborators on this research include OSU, the University of Melbourne, University of Technology/Sydney, Deakin University, the Australian National University, and the University of Leeds in the United Kingdom.

Funding has been provided by the Australian National Health and Medical Research Council, the U.S. National Institutes of Health, the Linus Pauling Institute and other groups in Australia and Finland.

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Joseph Beckman, 541-737-8867

Animal trapping records reveal strong wolf effect across North America

CORVALLIS, Ore. – Scientists have used coyote and red fox fur trapping records across North America to document how the presence of wolves influences the balance of smaller predators further down the food chain.

From Alaska and Yukon to Nova Scotia and Maine, the researchers have demonstrated that a “wolf effect” exists, favoring red foxes where wolves are present and coyotes where wolves are absent.

This effect requires that enough wolves be present to suppress coyotes over a wide area. Fur trapping records from Saskatchewan and Manitoba reveal that where wolves are absent in the southern agricultural regions of each province, coyotes outnumber foxes on average by 3-to-1. However, where wolves are abundant in the North, the balance swings dramatically in favor of foxes on average by 4-to-1 and at an extreme of 500-to-1 at one site.

In between is a 200-kilometer (124-mile) transition zone where too few wolves are present to tip the balance between coyotes and foxes.

The results of the study by Thomas Newsome and William Ripple in the Oregon State University Department of Forest Ecosystems and Society were published today in the Journal of Animal Ecology by the British Ecological Society.

“As wolves were extirpated across the southern half of North America, coyotes dramatically expanded their range,” said Newsome, a post-doctoral researcher. “They were historically located in the middle and western United States, but they dispersed all the way to Alaska in the early 1900s and to New Brunswick and Maine by the 1970s.”

“So essentially coyotes have been dispersing into wolf and red-fox range in the North but also into areas where wolves are absent but red fox are present in the East,” Newsome added.

Newsome came to the United States on a Fulbright scholarship from Australia where he earned a Ph.D. from the University of Sydney and specialized in the study of dingoes, that continent’s top predator. There’s a debate among Australians, he said, about the potential role of dingoes in suppressing introduced pests that have already decimated wildlife there.

“Over the last 200 years, Australia has had the highest extinction rate in the world,” Newsome said. “The debate is about whether the dingo can provide positive ecological benefits. Where dingoes have been removed, the impacts of introduced red foxes and feral cats have been quite severe on native fauna.”

Dingoes are managed as a pest in New South Wales, the country’s most populous state. To reduce dingo predation in the livestock industry, Australia also maintains the world’s longest fence, which runs for 5,500 kilometers (3,400 miles) in an attempt to exclude dingoes from almost a quarter of the continent.

In North America, the effect of wolves on coyotes and red foxes provides a natural case study that can be instructive for Australians. “Australians can learn a lot from how wolves are managed in North America, and Americans can learn from the ecological role of the dingo,” Newsome said.

As coyotes have expanded in North America, they have become a major cause of concern for the livestock industry. In the United States in 2004, researchers estimated annual losses due to coyote predation on sheep and cattle at $40 million. To reduce those damages, the Wildlife Service of the U.S. Department of Agriculture has a program to reduce coyote numbers, an effort that has drawn criticism from conservation groups.

In reviewing the fur trapping data from two U.S. and six Canadian jurisdictions, Newsome and Ripple eliminated potential sources of bias such as records from fur farms that raise foxes. The fur prices of coyotes and red foxes are also strongly correlated, and the two species occupy much of the same types of habitat, so they are equally likely to be targeted and caught in hunters’ traps.

“This study gives us a whole other avenue to understand the ecological effects of wolves on landscapes and animal communities,” said Ripple. He has studied the influence of carnivores on their prey — such as deer and elk — and on vegetation from aspen trees to willows. He and his colleagues have shown that the removal of top predators can cause dramatic shifts within ecosystems.

Wolves are naturally recolonizing many areas of the United States following their reintroduction into Yellowstone National Park and surrounding areas in 1995. Scientists are studying wolf interactions with other species, and in particular, there is interest in determining whether recolonizing wolves will suppress coyote populations and have cascading effects on red foxes and other species.

Newsome received funding from the Australian-American Fulbright Commission and from the government and universities of New South Wales in Australia.

 

Media Contact: 
Source: 

Thomas Newsome, 541-737-3197

Wiliam Ripple, 541-737-3056

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Coyote (Photo: Shawn McCready)

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Red fox (Photo: Kelly Colgan Azar)

Gray Wolf, credit- Doug McLaughlin copy 2

Gray wolf (Photo: Doug McLaughlin)

ODFW, OSU to survey hunters about use of lead ammunition

CORVALLIS, Ore. – The Oregon Department of Fish and Wildlife and Oregon State University are collaborating on an effort to survey Oregon hunters about their use and knowledge of lead ammunition.

The random sample of 4,200 Oregon hunters will begin later this month and those selected should receive a letter from ODFW within the next two weeks. Oregon has approximately 250,000 hunters and the survey will include hunters from each geographic region of the state.

The use of lead ammunition has become a national issue because of impacts to wildlife and human health concerns, according to Ron Anglin, ODFW Wildlife Division administrator. Last year, California passed a law banning the use of lead ammunition for all hunting in the state beginning in 2019; other states have adopted voluntary measures encouraging the use of ammunition made from alternative compounds.

“There is no proposal to ban or limit use of lead ammunition in Oregon, but developments outside of Oregon could affect the use of lead ammunition within the state,” Anglin said. “The Environmental Protection Agency was petitioned to ban the use of lead in ammunition on a nationwide basis and there is the potential of condors being restored in northern California.”

The California legislature passed a law banning lead ammunition to protect endangered California condors, according to Dana Sanchez, an OSU Extension wildlife specialist and one of the project leaders. Condors can become ill after scavenging on animals that have been killed by lead bullets. The birds ingest lead fragments and can become sick or die, she said.

“Historically, Oregon has had condors, though none are known to live here now,” Sanchez pointed out. “However, there are efforts to re-establish populations in northern California and if they are successful, it is only a matter of time before condors begin frequenting the southern portions of Oregon.

“Once condors appear in Oregon, they would be subject to federal protection under the Endangered Species Act,” she added.

Sanchez said some conservation organizations in the state are monitoring lead levels in birds of prey brought into wildlife rehabilitation centers. There is increasing concern that lead exposure may be causing impacts to raptors and eagles in some areas, she said.

“This could lead to an initiative or other efforts to eliminate or restrict the use of lead ammunition,” Sanchez said.

The survey was developed by the OSU Survey Research Center, which will collect the data for ODFW and the OSU Wildlife Extension program. Survey results will be used to inform discussions among agencies, groups and others about any potential restrictions in the use of lead ammunition.

The purpose of the survey, Anglin said, is to gather information from the group of stakeholders who would be most affected by any restrictions on lead ammunition – Oregon hunters.

“Ideally, we would like to survey all Oregon hunters, but that is expensive,” Anglin said. “However, by selecting a random sample of hunters from regions across the state, we should get a clear picture of how Oregon hunters feel about lead ammunition and possible alternatives.”

Persons not chosen for the survey are welcome to provide comments on lead ammunition directly to the Oregon Department of Fish & Wildlife at a special email address: ODFW.wildlifeinfo@state.or.us

Anglin said the ODFW/OSU project team plans to conduct a similar survey of non-hunting Oregonians in the future.

Media Contact: 
Source: 

Ron Anglin, 503-947-6301; ODFW.wildlifeinfo@state.or.us; Dana Sanchez, 541-737-6003; dana.sanchez@oregonstate.edu