OREGON STATE UNIVERSITY

environment and natural resources

Marine ecologist offers suggestions for achieving a strong, lasting ‘blue economy’

BOSTON – Incentive-based solutions offer significant hope for addressing the myriad environmental challenges facing the world’s oceans – that’s the central message a leading marine ecologist delivered today in during a presentation at the annual meeting of the American Association for the Advancement of Science. 

Jane Lubchenco, a distinguished professor in the Oregon State University College of Science, shared lessons from around the world about ways “to use the ocean without using it up” as nations look to the ocean for new economic opportunities, food security or poverty alleviation.

Elizabeth Cerny-Chipman, a former postdoctoral scholar under Lubchenco who’s now a Knauss Fellow at the National Oceanic and Atmospheric Administration, co-authored the presentation, titled “Getting Incentives Right for Sustained Blue Growth: Science and Opportunities.”

In her presentation, Lubchenco pointed out that achieving the long-term potential of blue growth will require aligning short- and long-term economic incentives to achieve a diverse mix of benefits. Blue growth refers to long-term strategies for supporting sustainable growth in the marine and maritime sectors as a whole.

“If we harness human ingenuity and recognize that a healthy ocean is essential for long-term prosperity, we can tackle the enormous threats facing the ocean,” Lubchenco says, “and we can make a transition from vicious cycles to virtuous cycles.”

Lubchenco and her collaborators note that the world’s oceans are the main source of protein production for 3 billion people; are directly or indirectly responsible for the employment of more than 200 million people; and contribute $270 billion to the planet’s gross domestic product.

“The right incentives can drive behavior that aligns with both desired environmental outcomes and desirable social outcomes,” Lubchenco says.

The first step in building increased support for truly sustainable blue growth, she says, is highlighting its potential. That means working with decision-makers to promote win-win solutions with clear short-term environmental and economic benefits. Governments, industry and communities all have important roles to play, Lubchenco notes.

“Another key step is transforming the social norms that drive the behavior of the different actors, particularly in industry,” Lubchenco says. “Finally, it will be critical to take a cross-sector approach.

“Some nations, like the Seychelles, Belize and South Africa, are doing integrated, smart planning to deconflict use by different sectors while also growing their economies in ways that value the health of the ocean, which is essential to jobs and food security. They are figuring out how to be smarter about ocean uses, not just to use the ocean more intensively.”

Prior to her presentation, Lubchenco gave a related press briefing on how to create the right incentives for sustainable uses of the ocean.

In November 2016, Lubchenco, Cerny-Chipman, OSU graduate student Jessica Reimer and Simon Levin, the distinguished university professor in ecology and evolutionary biology at Princeton University, co-authored a paper on a related topic for the Proceedings of the National Academy of Sciences.

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By Steve Lundeberg, 541-737-4039

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Catch share

"Catch share" fisheries program

2015-16 weather event took toll on California beaches; not so much for Oregon, Washington

CORVALLIS, Ore. – The 2015-16 El Niño was one of the strongest climate events in recent history with extraordinary winter wave energy, a new study shows, though its impact on beaches was greater in California than in Oregon and Washington.

The reason, researchers say, is that the Pacific Northwest had experienced comparatively mild wave conditions in the years prior to the onset of the El Niño, while California was experiencing a severe drought and “sediment starvation.”

Results of the study are being published this week in Nature Communications.

“Rivers still supply the primary source of sand to California beaches, despite long-term reductions due to extensive dam construction,” said Patrick Barnard, a geologist with the U.S. Geological Survey and lead author on the study. “But as California was in the midst of a major drought, the resulting lower river flows equated to even less sand being carried to the coast to help sustain beaches.

“Therefore, many of the beaches in California were in a depleted state prior to the El Niño winters, and thereby were subjected to extreme and unprecedented landward erosion due to the highly energetic winter storm season of 2015-16.”

The West Coast, on average, experienced a “shoreline retreat” – or degree of beach erosion – that was 76 percent above normal and 27 percent higher than any other winter on record, eclipsing the El Niño events of 2009-10 and 1997-98. Coastal erosion was greatest in California, where 11 of the 18 beaches surveyed experienced historical levels of erosion.

Peter Ruggiero, an Oregon State University coastal hazards expert and co-author on the study, said Oregon and Washington were not affected to the same extent.

“You would have thought that there would be massive damage associated with erosion in Oregon and Washington with the strength of this El Niño,” said Ruggiero, a professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences. “But the previous three years had mild winters and therefore the sand buildup was much higher than in California. It helped the Northwest offset the potential erosion from the El Niño.”

Oregon and Washington also have broader beaches than in California, Ruggiero pointed out, which also eases the erosion of sand dunes and impacts to development.

The 2015-16 El Niño, in some ways, was stronger than the 1982-83 event, which caused an estimated $11.5 billion in damages, the researchers say in the study. Only a portion of the damage was directly related to coastal erosion, with damage to houses and roads, they note. Most of the impact was from related storms, flooding and other damage that occurred inland.

The Nature Communications study is important, the authors say, because it is one of the first attempts to document the oceanographic “forcing” directly related to beach impacts created by El Niño. The study documents the amount of power created by winter storm waves, using height and “period” – or the length of time between waves. It is the level of forcing, along with relative beach health, that dictates the amount of erosion that occurs and the associated impacts from that erosion.

“During an El Niño, the nearshore experiences higher water levels because of the storms and the fact that the water is warmer and expands,” Ruggiero said. “In Oregon, the water was about 15-17 centimeters (roughly 6-7 inches) higher than average, which led to higher storm tides.”

Although Northwest beaches were buffered from catastrophic damage, Ruggiero said, they did experience significant retreat. And it may take a while for the beaches to rebuild.

“We’re not completely recovered yet, and it may take years for some beaches to build back up,” he said. “After the 1997-98 El Niño, it took some beaches a decade to recover.”

Ruggiero, his students and colleagues have been monitoring Northwest beaches since 1997, and in 2015, they received a National Science Foundation rapid response grant to study the impact of El Niño on beaches. Ruggiero also receives support from the Northwest Association of Networked Ocean Observing Systems (NANOOS) and the U.S. Army Corps of Engineers for additional monitoring.

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Peter Ruggiero, 541-737-1239, pruggier@coas.oregonstate.edu; Patrick Barnard, 831-460-7556, pbarnard@usgs.gov

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South Beach, Oregon
Oregon's South Beach

 

(Left: Crescent Beach in Callifornia. Photos by Nick Cohn, Oregon State University. https://flic.kr/p/RwDLsb)

Leading marine researcher says scientists must speak, reach out and integrate into society

CORVALLIS, Ore. – A leading global marine ecologist today called on scientists to increasingly engage the public by demonstrating the value of their research.

Jane Lubchenco, a distinguished university professor in the Oregon State University College of Science and advisor in marine studies for the university, urged this action during a time in which she said scientific facts are being called into question.

She made the points in a commentary titled “Environmental Science in a Post-Truth World” published today in Frontiers in Ecology and the Environment, the journal of the Ecological Society of America.

“Access to information, and critical thinking, are essential for an informed democracy,” Lubchenco says. “A post-truth world, a U.S. cabinet full of climate deniers, suppression of science and scientists all threaten – seriously threaten – our democracy. Resistance is appropriate, but now, more than ever, scientists also need to engage meaningfully with society to address intertwined environmental and societal problems.”

Lubchenco, an internationally recognized expert on marine ecology, environmental science and climate change, is urging researchers to act boldly and creatively to counteract what she called a “pervasive” dismissal of facts exemplified by President Trump’s labeling of climate change as a hoax.

She outlines three parallel approaches for scientists to “rise to the occasion, find solutions and help create a better world”:

1)    Demonstrate the merits of science by making it accessible, which includes eschewing jargon in favor of plain language and acting in such a way that shows scientists are warm, caring human beings;

2)    Provide hope by highlighting successes, creating even more successes, and figuring out how to bring them to a meaningful scale;

3)    Modify academic reward structures to incentivize public engagement as a core responsibility.

Lubchenco, a former administrator of the National Oceanic and Atmospheric Administration (2009-13) and the first U.S. Science Envoy for the Ocean (2014-16), makes those points and others in her invited editorial.

She says facts are losing ground to appeals to emotion and personal belief in the shaping of public opinion. Lubchenco sounds a clarion call for the scientific community to do everything in its power to stand up for science and also to make research findings understandable, credible, relevant and accessible.

That includes, Lubchenco says, “getting off our lofty perches and being more integrated into society.”

“Fortunately, many politicians and other citizens still believe that decisions based on science are better decisions than those not based on science,” says Lubchenco, past president of the Ecological Society of America, the nation’s largest professional society of ecologists.

The challenges of the post-truth era demand that scientists serve in a way that responds to needs through interactions with citizens based on humility, transparency and respect, she says.

“Now’s the time for all scientists to take a quantum leap into greater relevance by helping people to understand how important our work really is,” Lubchenco says. “For example, the world has finally begun to make tangible progress in addressing climate change. We can’t let a post-truth mentality derail that or the other things we do to improve people’s lives.”

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Steve Lundeberg, 541-737-4039

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Jane Lubchenco

Third Oregon climate assessment report shows state still warming, despite frigid winter

CORVALLIS, Ore. – Don’t let this winter fool you. Oregon’s climate continues to warm; there are impacts on the state’s physical, biological and human-managed systems; and more studies are pointing to greenhouse gas emissions as the reason for these climate trends and events.

That is the conclusion of the third Oregon Climate Assessment Report, a synthesis of peer-reviewed scientific studies over the past three years. The legislatively mandated report was produced by the Oregon Climate Change Research Institute at Oregon State University and is being presented this month to key Oregon political leaders.

“Oregonians shouldn’t be swayed by this winter, which is colder than any of the ones we’ve had since 1990,” noted Philip Mote, director of the OSU center and a co-author on the report. “Overall, temperatures are still getting warmer – in Oregon, throughout the United States, and globally – and the impacts are very real.

“For Oregonians, it means warmer temperatures, lower snowpack and less water during the summer. And more and more studies are confirming greenhouse gas emissions as the cause.”

Kathie Dello, associate director of the Oregon Climate Change Research Institute, points out that although December of 2016 was the 11th coldest December on record in Oregon in 122 years of monitoring, the year was still among the top 10 warmest years on record for the state.

The climate assessment report, led by Meghan Dalton, a research assistant with the institute in the College of Earth, Ocean, and Atmospheric Sciences at OSU, looked at more than 300 studies published from 2013-16 by researchers at universities, state and federal agencies, and elsewhere. Dalton led a team of researchers who synthesized the literature and developed the report.

“The year 2015 has been described as foreshadowing what we can expect as normal conditions by the mid-21st century,” Dalton said. “There were warmer temperatures that led to drought, low snowpack, and greater wildfire risk, with less water in the summer. That appears to be our future.”

Snowpack in the past three years has varied greatly, according to Dello.

“In 2015, we basically had no snow to speak of,” Dello said. “In 2016, we had a lot of snow, but most of it got wiped out by warm temperatures in late winter and early spring. So far this year, we have had a lot of snow, but warmer temperatures are moving in, and we still have a lot of winter left. We’re cautiously optimistic. Large year-to-year changes like that are still expected, even in a warming climate.”

The report notes that a warming climate and earlier spring may have a few beneficial results. Farmers, for example, may benefit from a longer growing season, though water could be an issue for some crops.

The report analyzes potential impacts of climate change for Oregon’s many regions. Among the findings:

  • The Oregon Coast: Sea level rise will increase the risk of erosion and flooding and higher estuary temperatures will challenge migrating salmon and steelhead. One study estimated that warming of Yaquina Bay by 1.3 to 2.9 degrees (F) would result in 40 additional days of temperatures not meeting the criteria for protecting salmonids.
  • The Willamette Valley: Heat waves are expected to become longer, more common and more intense; operating rules for reservoirs may have to change to balance flood risk and summer water supply; air quality will decline, and wildfire risk will increase. A study of fire activity concluded that there will be a three-fold to nine-fold increase in the amount of area burned in the basin by the year 2100.
  • The Cascade Mountains: More precipitation will fall as rain instead of snow, with elevations between 3,000 feet and 6,000 feet being the most sensitive. In addition to potential impacts on ski resorts, there likely will be a change in when water is available. Cascades forests will probably be subject to more wildfire, drought, insect damage and disease, and some studies suggest that woodlands will shift from predominantly conifer to mixed conifer forests. The risk of increased incidence of respiratory illness from wildfire smoke is a top public health risk in Jackson County.
  • Eastern Oregon: Water will be a huge issue in the east with snowpack decline, and the same forest issues face the Blue Mountains as the Cascades. Increased wildfire risk may create more days of heavy smoke affecting public health, and fires will threaten the forests. Salmon in the John Day basin and other river systems will be challenged with warmer temperatures, and rangeland and sagebrush habitat is threatened by non-native weeds and grasses.

“A lot of the studies we cited focus on the physical aspects of warming, from snowpack to wildfire, but there are a lot of people who will be affected,” Dello said. “We can’t forget that Oregonians, their families, their jobs and their resources are at risk. There is still time to do something, but time is running short.”

A copy of the report is available at http://occri.net/

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Kathie Dello, 541-737-8927, kdello@coas.oregonstate.edu; Phil Mote, 541-913-2274, pmote@coas.oregonstate.edu

Off-grid power in remote areas will require special business model to succeed

CORVALLIS, Ore. – Low-cost, off-grid solar energy could provide significant economic benefit to people living in some remote areas, but a new study suggests they generally lack the access to financial resources, commercial institutions and markets needed to bring solar electricity to their communities.

Around the world, more than 1.2 billion people lack access to basic electricity service. The majority of those people are living in developing nations, in rural or isolated areas with high rates of poverty. Steep costs and remote terrain often make it impractical or even impossible to extend the electric grid. 

Developing a successful business model that could deliver off-grid power to this market will require addressing challenges unique to the population, an Oregon State University researcher concluded in a study published recently in Renewable and Sustainable Energy Reviews.

“Surviving and growing in this market is very different than in a typical commercial enterprise,” said Inara Scott, an assistant professor in the College of Business. “There are a lot of people working on off-grid solar products on the small scale, but the problem becomes how can they scale the programs up and make them profitable?” 

When rural, isolated communities do gain access to solar power, the impact on residents can be profound, Scott said. Children are more likely to go to and complete schooling, because they have light to study by. Kerosene lamps, which create a lot of indoor air pollution, are no longer needed, improving people’s health. And work hours are increased, giving people more time to earn money or build home-based businesses.

“Providing electricity starts an incredible cycle of improvement for communities without reliance on charities or government aid,” she said. “There are also environmental benefits to encouraging sustainable development using renewable resources.” 

The market for small solar lighting and charging units has grown dramatically in the last few years, and solar home systems offer cleaner, safer and cheaper lighting over time than kerosene, the primary alternative for lighting in developing nations. But even a small cost can be out of reach for people whose annual incomes are often less than $3,000 per year, Scott said.

She examined successful business models for serving these populations, known as “base of the pyramid” markets, and successful renewable energy enterprises, looking for intersections that might aid businesses looking to market solar energy to base-of-pyramid markets. 

Scott found that a successful enterprise would include four primary components, and she developed a framework around them. Her recommendations:

  • Community interaction: Work with local communities to understand local norms, culture, social issues and economic systems that might influence the effort.
  • Partnerships: Join forces with other companies, government organizations, non-profit groups or non-governmental organizations to share ideas and resources and gain support.
  • Local capacity building: People in the community may lack product knowledge and have little experience with technology, while the community may not have typical distribution channels. Consider the potential customers as both producers and consumers, training local entrepreneurs as distributors, marketers and equipment installation/repair technicians.
  • Barriers unique to the off-grid market: Address issues such as financing of upfront costs, which may be prohibitive to consumers; educate people on the products and their benefits; build trust in quality and reliability; and develop multiple strong distribution networks.

“You’re not going to be successful just trying to sell a product,” she said. “This is really a social enterprise, with the goal of trying to bring people out of poverty while also emphasizing sustainable development.” 

There are a lot of socially-minded enterprises with good intentions that would like to work in these rural, remote and high-poverty areas, Scott noted. Her framework could serve as a checklist of sorts for organizations looking to put their ideas into action, she said.

“It’s a way to pause for a minute and ask yourself if you have all the right pieces in place to be successful,” she said.

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Inara Scott, 541-737-4102, Inara.Scott@oregonstate.edu

New study: Weakening of North Atlantic current can be prevented by reducing carbon emissions

CORVALLIS, Ore. – Continued melting of the Greenland Ice Sheet could have a significant impact on the Atlantic Meridional Overturning Circulation, a system of surface and deep ocean currents – including the Gulf Stream – in the Atlantic Ocean that keeps upper North America and Europe temperate.

A new international study incorporating a comprehensive assessment of Greenland Ice Sheet melting suggests the freshwater influx could weaken the AMOC over the next three centuries, though the impact could be offset if human-caused carbon emissions decline and global temperatures stabilize.

However, if carbon emissions continue unabated, there is a 44 percent likelihood of a collapse of the system by the year 2300, the researchers say.

The findings are being published in the journal Geophysical Research Letters.

“Previous studies and assessment reports, including those from the Intergovernmental Panel on Climate Change, have not considered the impacts on the AMOC from melting of the Greenland Ice Sheet, or they have looked at it simplistically,” said Andreas Schmittner, an Oregon State University climate scientist and co-author on the study.

“Our study, using eight state-of-the-science global climate models, incorporates a realistic assessment of the ice sheet melting and shows a definite weakening of the AMOC system, but one that can be partially mitigated by a decline in carbon emissions.”

The study also suggests that the freshwater influx from melting of the Greenland Ice Sheet will have less of an impact on the Atlantic Meridional Overturning Circulation than will overall global warming, rising sea surface temperatures, and intensification of the water cycle leading to more precipitation and evaporation.

“The good news is that we can still do something to lessen the impact of AMOC weakening and prevent an unlikely, but still possible collapse of the system,” said lead author Pepijn Bakker, a former post-doctoral researcher at Oregon State University now with the MARUM Center for Marine Environmental Studies at the University of Bremen in Germany.

“Our models predict that the ice sheet may not melt as rapidly as another recent study has suggested, but everything comes down to what will we in the United States, and people in other countries, do to lessen our carbon emissions.”

The Atlantic Meridional Overturning Circulation brings warm waters up from the tropics and transports cooler water to the south. A weakening of the system could mean that the North Atlantic would not warm as rapidly or thoroughly as it does now, affecting regional climate in North America and northern Europe.

The AMOC also is important for preserving ocean ecosystems, affecting nutrient transport.

“A weakening of the AMOC system would probably lead to more stratification of ocean waters and less biological productivity,” Schmittner said. “It may create more sea ice in the North Atlantic, which could be beneficial in some ways. At the same time, however, it would likely reduce the transport of cooler water to the south and shift rainfall patterns near the equator.”

The study was supported by the National Oceanic and Atmospheric Administration and several other agencies.

 

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Andreas Schmittner, 541-737-9952, aschmittner@coas.oregonstate.edu;

Pepijn Bakker, 004942121865435, pbakker@marum.de

Study finds less fragmentation in muzzleloading and black powder cartridge rifles

CORVALLIS, Ore. – A new study found that traditional bullets for muzzleloading rifles and black powder rifle cartridges fragment less upon impact and may leave far fewer lead fragments in game than a modern high-velocity rifle bullet.

The findings suggest that hunters using those styles of guns may have a reduced risk of secondary lead poisoning from consuming game meat, and that there may be a reduced risk to scavenging animals as well, compared to ammunition for modern rifles that also contain lead. 

Results of the study, by researchers in the Department of Fisheries and Wildlife at Oregon State University, have been published in the Journal of Fish and Wildlife Management.

Bullet fragmentation has been well-described in many modern, high-velocity rifles, but not for black-powder cartridge rifles or muzzleloading firearms, said Clinton Epps, a wildlife ecologist at Oregon State and co-author on the study. 

“There is a lot more complexity to the lead versus non-lead ammunition discussion than many people realize and the black powder/muzzleloader niche of hunters needs to be included in the conversation,” Epps said.

To study the fragmentation, the researchers evaluated a traditional .54 caliber round ball and a modern-designed .54 caliber conical bullet for muzzleloaders and two types of .45-70 caliber black powder rifle cartridges, and compared them with a modern, lead-core high-velocity bullet (Remington Core-Lokt) for a .30-06. 

They found that the modern .30-06 bullets retained a mean 57.5 percent of their original mass, with the remaining 42.5 percent fragmenting. Mean mass retention for muzzleloader and black powder cartridge bullets ranged from 87.8 percent to 99.7 percent.

“We tested penetration and fragmentation for each bullet type in both water and ballistics gel,” said Dana Sanchez, an OSU wildlife Extension specialist and lead author on the article. “Obviously, these kinds of artificial tests cannot replicate conditions in the field, but the striking differences in fragmentation suggests follow-up tests on game animals harvested in actual hunting situations may be warranted.” 

Muzzleloaders use black powder, typically made from charcoal, potassium nitrate and sulfur, and loaded from the muzzle using loose components rather than self-contained cartridges. Traditional hunting bullets for muzzleloaders are round balls made of pure lead and wrapped in a cloth patch to engage the rifling. Because of their low velocity and low potential for expansion, most states require muzzleloaders to have larger (greater than .45) calibers than modern high-velocity rifles.

“The speed of a bullet is a key factor in fragmentation, although there are other variables,” said Epps, who is a rifle builder, ballistics specialist and a hunter. “Black powder cartridges and round balls don’t go as fast, so they have to use a bigger bullet, which tends not to break apart as much.” 

Muzzleloader hunting is popular in many states, especially in the Midwest and the South, where special seasons allow hunters to use this method in addition to traditional rifle and archery hunts. Oregon has special muzzleloader tags for deer, elk and pronghorn antelope. Hunting with muzzleloaders and black powder rifles remains a comparatively small niche among hunters and the researchers emphasize that their study was solely intended to provide information on fragmentation that had been missing.

Oregon allows use of both lead and non-lead ammunition in big game hunting. And while non-lead ammunition choices for modern firearms are increasingly more available, Epps said, “non-lead options for muzzleloaders and other older-style firearms are still limited and may not function well in all rifles.” 

David Taylor, a graduate student in OSU’s Department of Integrative Biology, also was an author on the study and conducted the field work as part of an undergraduate project funded in part by the Undergraduate Research, Innovation, Scholarship and Creativity program at Oregon State.

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Clint Epps, 541-737-2478, Clinton.epps@oregonstate.edu; Dana Sanchez, 541-737-6003, dana.sanchez@oregonstate.edu

Despite evolutionary inexperience, northern sockeye manage heat stress

CORVALLIS, Ore. – Sockeye salmon that evolved in the generally colder waters of the far north still know how to cool off if necessary, an important factor in the species’ potential for dealing with global climate change.

Sockeyes, which spawn in fresh water and spend two to three years in the Pacific Ocean, range from southern Alaska south to the Columbia River.

Research by Oregon State University revealed that sockeyes at the northern edge of that range, despite lacking their southern counterparts’ evolutionary history of dealing with heat stress, nevertheless have an innate ability to “thermoregulate.”

Thermoregulation means that when their surroundings warm up too much, the fish will seek cooler water that precisely meets their physiological needs. A study conducted by an OSU researcher at an Alaska lake during a heat wave shed light on sockeyes’ ability to find the water temperatures they need.

Multiple earlier studies had demonstrated thermoregulation behavior among sockeye salmon at lower latitudes, but northern populations’ behavioral response to heat stress had largely gone unexamined.

While it may seem obvious that any fish would move around to find the water temperature it needed, prior research has shown thermoregulation is far from automatic – even among populations living where heat stress is a regular occurrence.

“Often what’s happened has been counterintuitive, so we had no idea what to expect,” said Jonathan B. Armstrong, assistant professor in the College of Agricultural Sciences’ Department of Fish and Wildlife, the lead author on the study. “About 40 million sockeye return to Bristol Bay every year. These huge salmon runs are a big part of the regional culture and economy, so how these fish respond to climate change will have very real effects on people’s lives. It’s encouraging that the sockeyes showed this innate capacity to respond.”

Results of the research were recently published in Conservation Physiology.

Armstrong and his collaborators at the University of Washington worked in 2013 at Little Togiak Lake – one of five major lakes in the Wood River watershed that drain into Bristol Bay, a fishery that produces nearly 70 percent of all the sockeye salmon caught in the United States. Bristol Bay is close to the 60-degree latitude that marks the northern boundary of the sockeyes’ primary range.

Adult sockeye salmon return to the Wood River system from the Bering Sea in early summer, then mature and develop secondary sexual traits before spawning later in the summer or at the beginning of fall.

During the time between entering fresh water and spawning, the fish group together in their lake’s epilimnion – the upper, warmer level of water in a thermally stratified lake. Usually the fish congregate, or stage, near tributary inlets and along shorelines.

During a staging period of unusually warm weather – maximum daily air temperatures hovered around 80 degrees for a week, the second-warmest heat wave on record – researchers used a seine to capture fish and outfitted 95 of them with devices that logged water temperatures at 20-minute intervals.

What they learned from the 40 recovered temperature loggers was that when the epilimnion temperature rose above about 12 degrees Celsius, or about 53 degrees, the fish thermoregulated by moving to tributary plumes or to deeper water.

By swimming away from the rising temperatures, the fish expended 50 percent less energy during the warmest conditions – 64 to 68 degrees – than they would have had they stayed put.

“The hotter it is, the more energy they burn, but these fish don’t just want the coldest water possible,” Armstrong said. “If they were cars looking for maximum fuel efficiency, they’d just find the coldest water, but instead it’s a Goldilocks sort of thing - they’re looking for not too warm, not too cold.

“They want their system to go fast enough for them to go through maturation before they spawn, where they go from these silver torpedoes to these crazy, exaggerated beasts of sexual selection with a red body and green jaws.”

Armstrong noted the broader message of the study is what it says about the ability of animals to exploit the kinds of diversity of temperature and diversity of habitat found in ecosystems that are intact and not heavily developed.

“There’s all this diversity and connectivity up there,” Armstrong said. “Fish have lots of options for coping with warming or environmental change in general.

“When we develop watersheds, we often simplify habitats and take away these options. In our research we are constantly stumbling across new and interesting ways that fish and wildlife thrive by exploiting diversity in temperatures, often at small spatial scales that would be very easy to overlook. This study is one more example of how all the little details matter, and they could be what save animals from climate change, or at least reduce the impacts.”

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Steve Lundeberg, 541-737-4039 

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Sockeye salmon

Bacteria discovery offers possible new means of controlling crop pest

CORVALLIS, Ore. – A bacterium common in insects has been discovered in a plant-parasitic roundworm, opening up the possibility of a new, environmentally friendly way of controlling the crop-damaging pest.

The worm, Pratylenchus penetrans, is one of the “lesion nematodes” -- microscopic animals that deploy their mouths like syringes to extract nutrients from the roots of plants, damaging them in the process. This particular nematode uses more than 150 species as hosts, including mint, raspberry, lily and potato.

The newly discovered bacterium is a strain in the genus Wolbachia, one of the world’s most widespread endosymbionts – organisms that live within other organisms. Wolbachia is present in roughly 60 percent of the globe’s arthropods, among them insects, spiders and crustaceans, and also lives in nematodes that cause illness in humans.

Postdoctoral scholar Amanda Brown in the Oregon State University Department of Integrative Biology was the lead author on the study, and recently accepted an assistant professor position at Texas Tech. Findings were published in the journal Scientific Reports.

Depending on the host species, Wolbachia can be an obligate mutualist – the bacteria and the host need each other for survival – or a reproductive parasite that manipulates the host’s reproductive outcomes in ways that harm the host and benefit the bacteria. Parasitic Wolbachia can cause its host populations to heavily skew toward female.

In the case of the crop-pest nematode, Pratylenchus penetrans, that Brown and her colleagues studied, the bacteria-host relationship appears to not be one of obligate mutualism – many examples of non-infected worms have been found, meaning the worm doesn’t rely on Wolbachia to survive.

But more study is needed to determine the exact nature of the relationship, said Dee Denver, an associate professor in the Department of Integrative Biology in the College of Science.

Whatever the relationship, simply discovering Wolbachia in Pratylenchus penetrans opens up the potential for managing the roundworm’s population via biocontrol rather than environment-damaging fumigants, such as methyl bromide, that are being phased out by the U.S. Environmental Protection Agency.

“We can use what’s already infecting them against them,” Denver said.

Nematode biocontrol would involve releasing Wolbachia-infected worms into farm fields whose worm populations weren’t infected. From there, a couple of situations, both favorable to the crops, might arise:

  •  The bacterium could hinder the worms’ ability to reproduce;
  •  It also might force the worm to devote energy to dealing with the bacterium, effectively distracting it from being as damaging to the crops as it otherwise would be.

Wolbachia is already being used as a biocontrol strategy in Colombia and Brazil, where infected mosquitoes are being released in an effort to control the Zika, dengue and malaria viruses. Mosquitoes are a vector for those diseases, but Wolbachia-infected mosquitoes pass the bacteria to their offspring, who lose their ability to transmit the diseases. Wolbachia also can interfere with the mosquitoes’ ability to reproduce at all.

“We can see where all of that goes and learn from it to help our decision making on how the strategy might get deployed to control the population of plant-parasitic nematodes,” Denver said. “One big thing with nematodes is the load. Many crops have some, but once you get above certain thresholds, fields go down and there are economic losses.”

In addition to the potential for an environmentally safe way to deal with a crop pest, the research is noteworthy for providing genomic evidence that nematodes, not arthropods, were the original Wolbachia hosts. The strain that OSU researchers discovered – known as wPpe – proved to be the earliest diverging Wolbachia, meaning the bacteria adapted to arthropods and then later evolved to reinvade nematodes.

“Were they originally reproductive parasites or play-nice mutualists?” Dee said. “These are outside the range of better-studied Wolbachia, so we don’t know, but we have preliminary data and we think they’re reproductive parasites.”

Another unanswered question: How widespread is Wolbachia among plant-parasitic nematodes?

“There are thousands of nematode species infecting plants,” Denver said. “Wolbachia has always been thought of as an arthropod thing, an insect thing. It was kind of a serendipitous discovery for us. We were sequencing genomes from nematodes for the purpose of understanding nematodes, and the mapping went to Wolbachia.”

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Steve Lundeberg, 541-737-4039

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Pratylenchus penetrans

Pratylenchus penetrans

The golden drool: Study finds treasure trove of info in saliva of foraging bears

CORVALLIS, Ore. – The rivers and streams of Alaska are littered in the summer and fall with carcasses of tens of thousands of salmon that not only provide a smorgasbord for hungry brown bears but are also the newest database in the arsenal of wildlife biologists.

A new study, published this week in the journal PLOS ONE, documents the ability of researchers to gather DNA from residual saliva on partially consumed salmon to the point that they can even identify individual bears from the genetic samples. The discovery should provide a significant boost to research on the population and health of brown bears, which can grow to a size of 1,500 pounds. 

“In the past, population estimates have been largely based on visual observations and on the analysis of fecal samples,” said Taal Levi, an assistant professor of fisheries and wildlife at Oregon State University and co-author on the study. “We found that using bear saliva is not only easier and cheaper as a research tool, it is more effective.”

In their study, the researchers examined 156 partially consumed salmon carcasses of lakeshore-spawning sockeye salmon in the Chilkoot watershed and stream-spawning chum salmon at Herman Creek in the Klehini watershed – both near Haines, Alaska. They also swabbed a total of 272 brown bear “scats,” or fecal samples, from those same locations. 

They found that the saliva collected from the salmon carcasses delivered a higher rate of genotyping success, allowing the researchers to identify individual bears more accurately and quickly than the fecal samples, and required significantly less labor.

“Bears love salmon because they are such a rich food source, and fortunately for us, the way they consume them lends itself to genetic monitoring,” said the study’s lead author, Rachel Wheat, who conducted the research as part of her doctoral dissertation at the University of California, Santa Cruz. 

“When salmon are plentiful, bears rarely eat the entire fish. In some cases, they only eat the brain, and we’ve found that swabbing along the edges of the braincase gives us the best results for extracting DNA,” Wheat said. “We also had success with swabbing inside distinct bite holes, and in the muscle tissue where the bears have stripped the skin off the salmon.”

The researchers were able to get brown bear genotypes for 55 percent of all the salmon carcasses sampled for saliva, compared to 34 percent for the scat samples. 

From a purely cost-savings perspective, the saliva sampling proved cheaper. It costs the researchers roughly $370 per bear to genetically identify individual animals using scat samples; the cost with saliva samples dropped to $118.

“This advance will help allow us to more effectively – and more economically – study one of the largest bears on the planet,” Wheat said. 

Levi agreed and also noted that the method does not have to be restricted to bear research. It could be adapted to other species, as well.

 “Many predators leave saliva on food remains,” he said. “We feel this type of saliva sampling could become an important tool for wildlife population monitoring.”

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Taal Levi, 541-737-4067, taal.levi@oregonstate.edu; Rachel Wheat, 719-439-3397, r.e.wheat@gmail.com

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Bear with salmon (Photo by Jennifer Allen)

Bear with salmon

Chum salmon (Photo by Rachel Wheat)

Chum salmon