OREGON STATE UNIVERSITY

college of forestry

Land management options outlined to address cheatgrass invasion

The study this story is based on is available online: http://bit.ly/ZO8Ezb

 

CORVALLIS, Ore. – A new study suggests that overgrazing and other factors increase the severity of cheatgrass invasion in sagebrush steppe, one of North America’s most endangered ecosystems.

The research found that overgrazed land loses the mechanisms that can resist invasion. This includes degradation of once-abundant native bunchgrasses and trampling that disturbs biological soil crusts. The work was published today in the Journal of Applied Ecology by researchers from Oregon State University, Augustana College and the U.S. Geological Survey.

“We think there are ways to assess the risks these lands face to reduce the impact of cheatgrass invasion,” said Paul Doescher, professor and head of the OSU Department of Forest Ecosystems and Society, and co-author on the study.

“In the future we should work cooperatively with ranchers and land managers to promote a diverse sagebrush and bunchgrass ecosystem,” Doescher said. “That type of community will protect the native plant and wildlife species and benefit sustainable rangeland use at the same time.”

Researchers suggested that one of the most effective restoration approaches would be to minimize the cumulative impact of grazing, by better managing the timing, frequency of grazing and number of animals.

The researchers also determined that, contrary to some previous suggestions, grazing does not reduce cheatgrass abundance. Cheatgrass was found by this study to be extremely tolerant of even intensive grazing, and the findings “raise serious concern” about proposals to use cattle grazing to help control its spread in areas where native bunchgrasses still persist.

The study outlines the complex ecological processes that can promote cheatgrass invasion and the indirect role overgrazing plays in that process. Increasing gaps and connection of gaps between once-abundant native bunchgrasses allow “a dramatic increase” in cheatgrass invasion, the study concluded. Such gaps could serve as a valuable “early warning indicator” and allow for management approaches that could help conserve and restore the land.

Cheatgrass threatens vast regions of the American West, especially the Great Basin in Nevada and surrounding states. These are areas which were once carpeted by millions of acres of native sagebrush, perennial bunchgrasses and associated wildlife that had evolved with little herbivore pressure. Cheatgrass displaces native grasses and wildlife, can increase fire frequency and ultimately cause an irreversible loss of these native shrub-steppe communities.

This also has grazing implications: cheatgrass is a short-lived annual grass that dries out quickly and provides lower quality forage for much of the year, compared to perennial bunchgrasses.

“Cheatgrass changes the fire regime, and as it spreads, can reach a tipping point,” said Michael Reisner, now an assistant professor at Augustana College who led this study as a doctoral student at OSU.

“After you cross that threshold, a major rangeland fire will come through that takes out the sagebrush, and in most cases the native ecosystem never recovers,” Reisner said. “Many of the plant and animal species that were there can disappear, mostly replaced by cheatgrass that offers poor forage for cattle.”

In a more resistant system, abundant native bunchgrasses can limit the size and connectivity of gaps, which minimizes the water and nutrients available to cheatgrass. Using data from 75 study sites, researchers found that high levels of cattle grazing were associated with reduced bunchgrass cover, with wider and more connections between the gaps that provided an opportunity for cheatgrass to invade.

Cattle trampling also appeared to disturb biological soil crust that offers a second defensive barrier against cheatgrass, and further speeds the invasion. Impacts are greater on the drier and warmer sites within this region.

If the level and amount of gaps indicates that it’s necessary, changes in grazing could help restore bunchgrass cover, maintain a diversity of native grass species and provide much better resistance to cheatgrass invasion, the study concluded. Continued research is needed to quantify the threshold levels of cattle grazing that would still maintain a healthy native ecosystem.

This work was supported by the U.S. Joint Fire Sciences Program, OSU, and the U.S. Geological Survey.

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Paul Doescher, 541-737-6583

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Intact rangeland

Intact rangeland


Grazing impacts

Grazing impacts

College of Forestry

About the OSU College of Forestry: For a century, the College of Forestry has been a world class center of teaching, learning and research. It offers graduate and undergraduate degree programs in sustaining ecosystems, managing forests and manufacturing wood products; conducts basic and applied research on the nature and use of forests; and operates 14,000 acres of college forests.

Starker Lectures to explore forest biomass issues

CORVALLIS, Ore. – The 2013 Starker Lecture Series at Oregon State University will begin Feb. 28 and continue through May with the theme “Forest Biomass: Energy and Beyond.”

Leading experts will examine the changing use of forest biomass to produce energy, fuels and chemicals, while considering technical, economic, environmental implications, wildlife, soils and other issues. The lecture series will conclude with a field trip in Benton and Lane County.

All of the events are free and open to the public, and all lectures will be on a Thursday afternoon from 3:30-5 p.m. in Richardson Hall Room 107.

A capstone field trip titled “A Tour of Forest Biomass – from the Ground Up!” will be held May 30 from 9 a.m. to 4 p.m. It will feature visits to forest biomass production sites and energy facilities, and a discussion of on-the-ground and facility supply and processing considerations, including technical, environmental and economic. Advance registration for the field trip, and more information about all of the lectures, is available online at http://starkerlectures.forestry.oregonstate.edu/

The speakers and their topics include:

  • Feb. 28: “Sustainable Integrated Forest Biorefineries,” with Shri Ramaswamy, professor at the University of Minnesota.
  • April 11: “Wood to Wing: Envisioning an Aviation Biofuels Industry Based on Forest Residuals in the Pacific Northwest,” with Michael Wolcott, director of the Institute for Sustainable Design at Washington State University.
  • May 2: “Environmental Considerations,” a panel discussion including Matthew Betts, associate professor at OSU, discussing forest wildlife habitat; Robert Harrison, a professor at the University of Washington discussing forest soil productivity; and Elaine Oneil, research scientist with the University of Washington discussing forest product life cycle analysis.
  • May 16: “Oregon’s Biomass Experience: An Integrated Approach to Forest Biomass,” with Matt Krumenauer, senior policy analyst with the Oregon Department of Energy.
  • May 30: “A Tour of Forest Biomass – from the Ground Up!” capstone field trip.

The Starker Lecture Series is sponsored by the Starker family in honor of T.J. and Bruce Starker, and is supported by the Oregon Forest Resources Institute and the OSU College of Forestry.

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Julie Howard, 541-737-1591

“Food for Thought” lectures on ag, food biotechnology begin in January

CORVALLIS, Ore. – The “Food for Thought” community lecture series will begin its eighth season this month at Oregon State University, bringing internationally recognized experts to discuss new options for food and fuel production, and implications for the environment, public health, and their economic and social viability.

The series emphasizes the roles of biotechnologies, in both novel and traditional forms.

All lectures will be at LaSells Stewart Center on the OSU campus on Wednesday or Thursday evenings, beginning at 7 p.m. The talks, which are followed by audience discussion and a chance to meet with speakers, are free and open to the public.

The series is part of OSU’s Outreach in Biotechnology program based in the College of Agricultural Sciences, and is designed to promote understanding of biotechnologies and related issues. The series and outreach program are supported by the OSU College of Agricultural Sciences and the OSU College of Forestry.

The first presentation will be Thursday, Jan. 24, by Prabhu Pingali, deputy director of agricultural development at the Bill and Melinda Gates Foundation. His lecture is titled “Green Revolution 2.0: making it work for hunger and poverty reduction in the developing world.” He will provide a retrospective on the first Green Revolution, including both its achievements and limitations in increasing global food supply and reducing poverty, and the urgent need for a second revolution to sustainably feed the world and enhance the prosperity of small farmers.

There are two other lectures in the series on Wednesday evenings:

  • Feb. 13: “Global economic and environmental impacts of agricultural biotechnology.” Nicholas Kalaitzandonakes, an endowed professor of agribusiness and the director of the Center for Economics and Management of Agrobiotechnology at the University of Missouri, will discuss the distribution of economic benefits and costs from the first wave of transgenic biotechnologies in agriculture, including for farmers, companies and consumers.
  • March 13: “Technology and food marketing in the age of animal welfare.” Joy Mench, a professor in the Department of Animal Science and the director of the Center for Animal Welfare at the University of California, Davis, will discuss what animal welfare means from both scientific and ethical perspectives, and how it is represented in the marketplace to enable consumers to make more informed purchasing and care decisions.

More information about the speakers and their presentations will be available online at http://oregonstate.edu/orb. Podcasts of 38 previous lectures are available online (downloadable from iTunes U and YouTube), as well as study guides prepared for teachers of undergraduate students and honors students, grades 10-12.

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Steve Strauss, 541-737-6578

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Prabhu Pingali

Prabhu Pingali

Climate change increases stress, need to restore grazed public lands

The study this story is based on is available in ScholarsArchive@OSU: http://bit.ly/PJux3q

 

CORVALLIS, Ore. – Eight researchers in a new report have suggested that climate change is causing additional stress to many western rangelands, and as a result land managers should consider a significant reduction, or in some places elimination of livestock and other large animals from public lands.

A growing degradation of grazing lands could be mitigated if large areas of Bureau of Land Management and USDA Forest Service lands became free of use by livestock and “feral ungulates” such as wild horses and burros, and high populations of deer and elk were reduced, the group of scientists said.

This would help arrest the decline and speed the recovery of affected ecosystems, they said, and provide a basis for comparative study of grazing impacts under a changing climate. The direct economic and social impacts might also be offset by a higher return on other ecosystem services and land uses, they said, although the report focused on ecology, not economics.

Their findings were reported today in Environmental Management, a professional journal published by Springer.

“People have discussed the impacts of climate change for some time with such topics as forest health or increased fire,” said Robert Beschta, a professor emeritus in the College of Forestry at Oregon State University, and lead author on this study.

“However, the climate effects on rangelands and other grazing lands have received much less interest,” he said. “Combined with the impacts of grazing livestock and other animals, this raises serious concerns about soil erosion, loss of vegetation, changes in hydrology and disrupted plant and animal communities. Entire rangeland ecosystems in the American West are getting lost in the shuffle.”

Livestock use affects a far greater proportion of BLM and Forest Service lands than do roads, timber harvest and wildfires combined, the researchers said in their study. But effort to mitigate the pervasive effects of livestock has been comparatively minor, they said, even as climatic impacts intensify.

Although the primary emphasis of this analysis is on ecological considerations, the scientists acknowledged that the changes being discussed would cause some negative social, economic and community disruption.

“If livestock grazing on public lands were discontinued or curtailed significantly, some operations would see reduced incomes and ranch values, some rural communities would experience negative economic impacts, and the social fabric of those communities could be altered,” the researchers wrote in their report, citing a 2002 study.

Among the observations of this report:

  • In the western U.S., climate change is expected to intensify even if greenhouse gas emissions are dramatically reduced.
  • Among the threats facing ecosystems as a result of climate change are invasive species, elevated wildfire occurrence, and declining snowpack.
  • Federal land managers have begun to adapt to climate-related impacts, but not the combined effects of climate and hooved mammals, or ungulates.
  • Climate impacts are compounded from heavy use by livestock and other grazing ungulates, which cause soil erosion, compaction, and dust generation; stream degradation; higher water temperatures and pollution; loss of habitat for fish, birds and amphibians; and desertification.
  • Encroachment of woody shrubs at the expense of native grasses and other plants can occur in grazed areas, affecting pollinators, birds, small mammals and other native wildlife.
  • Livestock grazing and trampling degrades soil fertility, stability and hydrology, and makes it vulnerable to wind erosion. This in turn adds sediments, nutrients and pathogens to western streams.
  • Water developments and diversion for livestock can reduce streamflows and increase water temperatures, degrading habitat for fish and aquatic invertebrates.
  • Grazing and trampling reduces the capacity of soils to sequester carbon, and through various processes contributes to greenhouse warming.
  • Domestic livestock now use more than 70 percent of the lands managed by the BLM and Forest Service, and their grazing may be the major factor negatively affecting wildlife in 11 western states. In the West, about 175 taxa of freshwater fish are considered imperiled due to habitat-related causes.
  • Removing or significantly reducing grazing is likely to be far more effective, in cost and success, than piecemeal approaches to address some of these concerns in isolation.

The advent of climate change has significantly added to historic and contemporary problems that result from cattle and sheep ranching, the report said, which first prompted federal regulations in the 1890s.

Wild horses and burros are also a significant problem, this report suggested, and high numbers of deer and elk occur in portions of the West, partially due to the loss or decline of large predators such as cougars and wolves. Restoring those predators might also be part of a comprehensive recovery plan, the researchers said.

The problems are sufficiently severe, this group of researchers concluded, that they believe the burden of proof should be shifted. Those using public lands for livestock production should have to justify the continuation of ungulate grazing, they said.

Collaborators on this study included researchers from the University of Wyoming, Geos Institute, Prescott College, and other agencies.

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Robert Beschta, 541-737-4292

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Hart Mountain

 

Hart Mountain, 1989

 

Hart Mountain

 

Hart Mountain, 2010

 

Grazing impacts in Montana

 

Grazing impact, Montana

 

Grazing impacts in Wyoming

Grazing impact, Wyoming

 

 

 

Sweet approach may produce metal casting parts, reduce toxicity

CORVALLIS, Ore. – Based on a new discovery by researchers at Oregon State University, the world’s multi-billion dollar foundry industry may soon develop a sweet tooth.

This industry, that produces metal castings used in everything from water pumps and jet engines to railroad and automobile parts, dates back thousands of years to before Greek and Roman times. It was important in the advance of human civilization, but still continues to evolve.

Some modern technologies use various types of “binders” to essentially glue together sands and other materials to form sophisticated molds, into which molten metals are injected to create products with complex shapes. Existing approaches work, but some materials used today, such as furan resins and phenol formaldehyde resins, can emit toxic fumes during the process.

However, experts in adhesion science in the OSU College of Forestry have discovered and applied for a patent on a new use of a compound that appears to also work surprisingly well for this purpose. They say it should cost less than existing binders, is completely renewable and should be environmentally benign.

It’s called sugar.

“We were surprised that simple sugar could bind sand together so strongly,” said Kaichang Li, an OSU professor of wood science and engineering. “Sugar and other carbohydrates are abundant, inexpensive, food-grade materials.

“The binder systems we’ve developed should be much less expensive than existing sand binders and not have toxicity concerns,” Li added.

Sugar is a highly water-soluble food ingredient, as anyone knows who has ever put a teaspoon of it in a cup of coffee. The OSU researchers discovered a novel way to make strong and moisture-resistant sand molds with sugar. An inaccurate reading of temperature in a baking oven helped lead to the important discovery, they said.

Li and an OSU faculty research assistant, Jian Huang, identified combinations of sugar, soy flour and hydrolyzed starch – or even just sugar by itself – that should work effectively as a binder in sand molds for making various types of metal parts.

This novel sand binder technology is ready for more applied research and testing, they said, and the university is seeking investors and industrial partners to commercialize it. Private sector financing of OSU research has increased 42 percent in the past two years, to $35 million, as part of its increasing emphasis on university/industry partnerships.

Sand-based moldings, which comprise about 70 percent of all metal castings, are used to make many metal products, often from aluminum or cast iron, but also from bronze, copper, tin and steel. They are a major part of the automobile industry, along with applications in plumbing materials, mining, railroad applications and many other areas.

Sugar and the other agricultural products used for this purpose should have no environmental drawbacks, since they largely decompose into just carbon dioxide and water. With the techniques developed at OSU, the use of sugar as a binder allows the creation of sand molds that gain strength rapidly and remain strong in high humidity environments, which is necessary for their effective use in industrial applications.

Li’s laboratory at OSU has developed other related products in recent years, such as a natural resin made from soy flour that is already being used commercially to replace the use of formaldehyde-based adhesives in the manufacture of some wood products.

For that achievement, five years ago he was given the Presidential Green Chemistry Challenge Award by the Environmental Protection Agency, which recognizes innovators who have helped reduce waste or toxins in manufacturing processes.

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Kaichang Li, 541-737-8421

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Sweet solution

Sugar

Mountain meadows dwindling in the Pacific Northwest

The study this story is based on is available in ScholarsArchive@OSU: http://bit.ly/SBCohC

 

CORVALLIS, Ore. – Some high mountain meadows in the Pacific Northwest are declining rapidly due to climate change, a study suggests, as reduced snowpacks, longer growing seasons and other factors allow trees to invade these unique ecosystems that once were carpeted with grasses, shrubs and wildflowers.

The process appears to have been going on for decades, but was highlighted in one recent analysis of Jefferson Park, a subalpine meadow complex in the central Oregon Cascade Range, in which tree occupation rose from 8 percent in 1950 to 35 percent in 2007.

The findings of that research, which was funded by the Pacific Northwest Research Station of the USDA Forest Service, were published in the journal Landscape Ecology.

The changes in Jefferson Park are representative of a larger force that is affecting not only this beautiful meadow at the base of Mount Jefferson, scientists say, but many areas of the American West.

“We worry a lot about the loss of old-growth forests, but have overlooked declines in our meadows, which are also areas of conservation concern,” said Harold Zald, a research associate in the College of Forestry at Oregon State University and lead author of this study.

“The first awareness of declining meadows dates back to the 1970s, and we’ve seen meadow reduction at both high and low elevations,” Zald said. “Between climate change, fire suppression and invasive species, these meadows and all of the plant, animal and insect life that depend on them are being threatened.

“Once trees become fully established, they tend to persist, and seed banks of native grass species disappear fairly quickly,” he said. “The meadows form an important part of forest biodiversity, and when they are gone, they may be gone forever.”

The meadow decline takes place over several decades, like the melting of glaciers. This also provides a way to gauge long-term climate change, Zald said, since the forces at work persist through seasonal, annual and longer patterns that are variably more wet, dry, hot or cold than average.

“It takes a long time to melt a glacier or fill in a meadow,” he said. “It’s a useful barometer of climate change over decadal time periods.”

In this study, it appears that snowpack was a bigger factor than temperature in allowing mountain hemlock tree invasion of Jefferson Park, a 333-acre meadow which sits at the northern base of Mount Jefferson, a towering 10,497-foot volcano northwest of Bend, Ore. Seedlings that can be buried by snow many months every year need only a few more weeks or months of growing season to hugely increase their chance of survival.

The study also found surprising variability of tree invasion even within the meadow, based on minor dips, debris flows or bumps in the terrain that caused changes in snowpack and also left some soils wetter or drier in ways that facilitated tree seedling survival.

“The process of tree invasion is usually slow and uneven,” Zald said. “But if you get all the conditions just right, some tree species can invade these meadows quite rapidly.”

There’s some suggestion that alpine meadows may simply move higher up on the mountain in the face of a changing climate, Zald said, but in many cases slopes become too steep, and poor-quality, unstable soils are unable to harbor much plant life.

In other research in recent years, Zald said, he looked at meadows on lower-elevation mountains in the Oregon Coast Range – what are called “grass balds” on the tops of some of the higher peaks, such as Mary’s Peak, the highest point in that range west of Corvallis, Ore. In a study of five Coast Range sites, Zald found that these “bald spots” had declined by an average of 50 percent between 1950 and 2000.

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Harold Zald, 541-758-7759

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Debris flow

Debris flow

 

Tree invasion

Tree invasion

“Moon Tree” to be recognized at OSU

CORVALLIS, Ore. – The “moon tree,” a Douglas-fir grown from seeds that in 1971 orbited the moon on Apollo 14, will be celebrated in a ceremony on Wednesday, Oct. 10, at Oregon State University.

The seeds were taken around the moon by NASA astronaut Stuart Roosa, an Oregon smoke jumper early in his career, as part of an experiment to see if space travel would affect seed germination. Seedlings were later grown and given to various agencies and officials around the world, and the OSU tree was planted in 1976.

A plaque will be unveiled and university officials will make presentations at the event, which begins at 2 p.m. at the east entrance to Peavy Hall. The event, which is free and open to the public, is sponsored by the OSU College of Forestry and the Oregon NASA Space Grant Consortium.

 

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Joe Majeski, 541-737-746

“Semi-dwarf” trees may enable a green revolution for some forest crops

The study this story is based on is available online: http://bit.ly/RVsIAH

CORVALLIS, Ore. – The same “green revolution” concepts that have revolutionized crop agriculture and helped to feed billions of people around the world may now offer similar potential in forestry, scientists say, with benefits for wood, biomass production, drought stress and even greenhouse gas mitigation.

Researchers at Oregon State University recently outlined the latest findings on reduced height growth in trees through genetic modification, and concluded that several advantageous growth traits could be achieved for short-rotation forestry, bioenergy, or more efficient water use in a drier, future climate.

This approach runs contrary to conventional wisdom and centuries of tree breeding, which tried to produce forest trees that grow larger and taller, the researchers note. But just as the green revolution in agriculture helped crops such as wheat and rice produce more food on smaller, sturdier plants, the opportunities in forestry could be significant.

“Research now makes it clear that genetic modification of height growth is achievable,” said Steven Strauss, an OSU professor of forest genetics. “We understand the genes and hormones that control growth not only in crop plants, but also in trees. They are largely the same.”

In a study published in Plant Physiology, researchers inserted a number of genes into poplar trees, a species often used for genetic experiments, and valuable for wood, environmental and energy purposes. They described 29 genetic traits that were affected, including growth rate, biomass production, branching, water-use efficiency, and root structure. All of the changes were from modified gibberellins, plant hormones that influence several aspects of growth and development.

The range and variation in genetic modification can be accurately observed and selected for, based on hormone and gene expression levels, to allow production of trees of almost any height.

For example, for ornamental purposes it would be possible to grow a miniature poplar, or even a Douglas-fir, as a potted plant. 

And because height growth, in competition for sunlight, is a primary mechanism that trees use to compete for survival, there would be reduced concern about use of such genetically modified trees in a natural environment. On a long-term basis they would be unable to compete, shaded by larger trees and ultimately they would die out.

Scientists could also produce trees that might have a larger root mass, which should make them more drought-resistant, increase water use efficiency, increase elimination of soil toxins and better sequester carbon. This could be useful for greenhouse gas mitigation, bioremediation or erosion control. 

Smaller trees could also be selected that have sturdier trunks for some uses in short-rotation plantation forestry, significantly reducing the number of trees blown down by wind. And shorter, thicker and straighter trunks might create higher-value wood products in many tree species, Strauss said.

Some semi-dwarf trees produced by conventional tree breeding techniques are already an important part of the horticulture industry, allowing easier harvesting of fruit and higher yields. Genetic modification could add new characteristics and more scientific precision to the process, researchers said.

“The main limitation is the onerous regulatory structure for genetically-modified plants in the United States,” Strauss said. “Even short, safe and beneficial trees are unlikely to be able to bear the high costs and red tape inherent to obtaining regulatory approval.” 

This research has been supported by the U.S. Department of Energy, U.S. Department of Agriculture, National Science Foundation, and industry members of the Tree Biosafety and Genomics Research Cooperative at OSU.

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Steven Strauss, 541-737-6578

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Shorter trees

Short trees

For young birds, getting stressed out can be a good thing

CORVALLIS, Ore. – Many studies have found that high levels of hormones that are associated with stress are a sign of poor fitness and reduced chance of survival – but recent research on young songbirds found that some elevated hormones can be a good thing, often the difference between life and death.

The new research concluded that elevated levels of glucocorticoid hormones, which are part of the natural response to stress, were related to the movement, feeding, and anti-predator behaviors of juvenile birds.

The findings were made by researchers at Oregon State University with the Swainson’s thrush as an animal model.

There’s only about a one-in-three chance that juveniles of this bird species will survive, the study found, and it appeared to have more to do with their stress hormones than other factors such as vegetative cover or nesting site.

“In these birds, a little stress and elevated stress hormones were associated with greater survival,” said James Rivers, a researcher with the OSU Department of Forest Ecosystems and Society. “The conventional wisdom is that elevated levels of glucocorticoid hormones are bad for survival, but we found just the opposite.”

“Stress is more complex than we think,” he said.

The hormones associated with stress, which include cortisol in humans, can change the behavior and physiology of animals. If stress is too persistent and the hormone levels remain consistently too high, it appears to impede growth. But especially at vulnerable stages where the task is to keep up with the parents, get enough food to grow, or flee a predator, higher levels of stress hormones appear to improve survival chances.

This was one of the first studies of its type done in small songbirds, researchers said. Some previous research had suggested that increased hormone levels can allocate resources away from normal activities and have long-term health impacts.

The research was published in Functional Ecology, a professional journal. It was supported by the U.S. Department of Agriculture, the National Science Foundation and other agencies.

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James Rivers, 541-737-6581

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Stress in birds

Swainson's thrush