OREGON STATE UNIVERSITY

scientific research and advances

Sea star juveniles abundant, but recovery is anything but guaranteed

CORVALLIS, Ore. – An unprecedented number of juvenile sea stars have been observed off the Oregon coast over the past several months – just two years after one of the most severe marine ecosystem epidemics in recorded history nearly wiped the population out.

The appearance of the juveniles does not mean the threat of “sea star wasting disease” is over, researchers caution. A second round of the disease could be disastrous to the purple ochre (Pisaster ochraceus) and other sea stars, some of which are considered “keystone” species in marine habitats because of their influence on the ecosystem.

A team of Oregon State University scientists who have been monitoring the sea stars for years reported on their status this week in the journal PLOS ONE.

“When we looked at the settlement of the larval sea stars on rocks in 2014 during the epidemic, it was the same or maybe even a bit lower than previous years,” said Bruce Menge, the Wayne and Gladys Valley Professor of Marine Biology at Oregon State University and lead author on the study. “But a few months later, the number of juveniles was off the charts – higher than we’d ever seen – as much as 300 times normal.”

“It wasn’t a case of high settlement, or more sea stars being born. They just had an extraordinary survival rate into the juvenile stage. Whether they can make it into adulthood and replenish the population without succumbing to sea star wasting disease is the big question.”

Menge and his colleagues believe the reason for the high survival rate is the availability of more food. The young sea stars feed on larval and juvenile mussels and barnacles, competing with adult sea stars for the same food source. The scarcity of adults provided a temporary smorgasbord for the juveniles.

Sea star wasting disease first appeared in Oregon in the summer of 2014. In rocky intertidal habitats, disease rapidly depleted populations of the dominant sea star, Pisaster ochraceus. The sea stars first developed twisted arms, then showed deflation and lesions, and eventually lost arms and the ability to grip onto the substrate before finally disintegrating completely.

Over a period of about 15 months, the disease reduced the overall sea star population by 63 to 84 percent at different site along the Oregon coast, and reduced the Pisaster ochraceus population by 80 to 99 percent. The epidemic ranged from Alaska to Baja California.

Scientists from Cornell University attributed the epidemic to a Sea Star-associated Densovirus and researchers in Washington say warmer water may have provided the trigger for the disease in that state.

But Menge’s research group found no association between water temperature and the disease outbreak in Oregon.

“The sea temperatures were warmer when the outbreak first began,” he said, “but Oregon wasn’t affected as early as other parts of the West Coast, and the outbreak reached its peak here when the sea temperature plummeted and was actually cooler than normal.”

The Cornell researchers found evidence of densovirus in the sea stars, the water column and in sediments. It occurs naturally and can become virulent, possibly as a result of stress.

“Something triggered that virulence and it happened on a coast-wide basis,” said Menge, a distinguished professor in the Department of Integrative Biology in OSU’s College of Science. “We don’t think it was a result of warming because conditions were different in Oregon than they were, for example, in Washington and likely other parts of the West Coast. Ocean acidification is one possibility and we’re looking at that now. Ultimately, the cause seems likely to be multi-faceted.”

Menge and his research team have been studying these intertidal rocky zones at different sites for as long as 32 years and analyzing the community structure. Historical research has shown that the ochre star is a “keystone” species because of its influence in these ecosystems, suggesting that the absence of so many adults could have a significant impact.

Ochre sea stars prey on barnacles and mussels and keep their populations under control. When left unchecked, mussel populations can explode, covering up algae and small invertebrates.

“The longer-term ecological consequences of this (disease) event could include wholesale elimination of many low zone species and a complete change in the zonation patterns of rocky intertidal communities along the West Coast of North America,” the authors wrote in their study.

Among the other findings the OSU researchers reported in PLOS One:

  • Sea stars that were continuously submerged, such as those in tidepools, had a higher rate of the disease than sea stars on rocks outside of tidepools where periodically they were above water;
  • During the last two years, the number of gooseneck barnacles has exploded along the coast – likely because they are not being preyed upon as heavily by adult sea stars;
  • Adult sea stars are much more likely to be affected by sea star wasting disease than juveniles, which may be because of longer exposure or some other factor.

The OSU research has been funded by the David and Lucile Packard Foundation, the National Science Foundation, the Kingfisher Foundation, and the Wayne and Gladys Valley Foundation.

Other authors on the study, all from OSU, include Elizabeth Cerny-Chipman, Angela Johnson, Jenna Sullivan, Sarah Gravem and Francis Chan.

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Bruce Menge, 541-737-5358, mengeb@oregonstate.edu

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This photograph of a disintegrating adult purple sea star, Pisaster ochraceus, is available at: https://flic.kr/p/nzd81S

“Eve” and descendants shape global sperm whale population structure

NEWPORT, Ore. – Although sperm whales have not been driven to the brink of extinction as have some other whales, a new study has found a remarkable lack of diversity in the maternally inherited mitochondrial DNA within the species.

In fact, the mitochondrial DNA from more than a thousand sperm whales examined during the past 15 years came from a single “Eve” sperm whale tens of thousands of years ago, the researchers say.

Results of the study are being published this week in the journal Molecular Ecology.

While the exact origins of this sperm whale “Eve” remain uncertain, the study shows the importance of her female descendants in shaping global population structure, according to Alana Alexander, a University of Kansas Biodiversity Institute researcher who conducted the study while a doctoral student at Oregon State University.

“Although the male sperm whale is more famous in literature and cinema through ‘Moby Dick’ and ‘In the Heart of the Sea,’ the patterns in mitochondrial DNA show that female sperm whales are shaping genetic differentiation by sticking close to home,” Alexander said.

Working in the genetic lab of Scott Baker, associate director of Oregon State’s Marine Mammal Institute, Alexander combined DNA information from 1,091 previously studied samples with 542 newly obtained DNA profiles from sperm whales. The new samples were part of a global sampling of sperm whale populations made possible by the Ocean Alliance’s “Voyage of the Odyssey,” a five-and-a-half year circumnavigation of the globe, including some of the most remote regions of the world.

The new sampling, including sperm whales from the previously un-sampled Indian Ocean, revealed global patterns of genetic differentiation and diversity.

“Sperm whales have been in the fossil record for some 20 million years,” said Baker, a co-author on the study, “so the obvious question is how one maternal lineage could be so successful that it sweeps through the global population and no other lineages survive? At this point, we can only speculate about the reasons for this success, but evolutionary advances in feeding preferences and social strategies are plausible explanations.”

The researchers say female sperm whales demonstrate strong fidelity to local areas, and both feeding habits and social structure are important to determine to better manage the species. “There is a real risk of long-term declines in response to current anthropogenic threats, despite the sperm whale’s large worldwide population,” the authors wrote.

“One concern is that this very strong local fidelity may slow expansion of the species following whaling,” said Baker, a professor of fisheries and wildlife who works at OSU’s Hatfield Marine Science Center in Newport, Oregon. “The Sri Lanka sperm whales, for example, don’t seem to mix with the Maldives whales, thus local anthropogenic threats could have a negative impact on local populations.”

The researchers note that while males are important for describing patterns in the nuclear DNA of sperm whales, ultimately the females shape the patterns within the species’ mitochondrial DNA.

“Although there is low mitochondrial DNA diversity there are strong patterns of differentiation, which implies that the global population structure in the sperm whale is shaped by females being ‘home-bodies’ – at the social group, regional and oceanic level,” Alexander said.

The study was funded by a Mamie Markham Award and a Lylian Brucefield Reynolds Award from the Hatfield Marine Science Center; a 2008-11 International Fulbright Science & Technology award to Alexander; and co-funded by the ASSURE program of the Department of Defense in partnership with the National Science Foundation REU Site program. Publication of the paper was supported in part by the Thomas G. Scott Publication Fund.

Other authors include Debbie Steel of OSU’s Marine Mammal Institute; Kendra Hoekzema, OSU Department of Fisheries and Wildlife; Sarah Mesnick, NOAA’s Southwest Fisheries Science Center; Daniel Engelhaupt, HDR Inc.; and Iain Kerr and Roger Payne, Ocean Alliance.

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Scott Baker, 541-867-0255, scott.baker@oregonstate.edu;

Alana Alexander, 785-864-9886, alana.alexander@ku.edu

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This photo of a sperm whale pod was taken by Gabriel Barathieu: commons.wikimedia.org/wiki/File:Sperm_whale_pod.jpg

Study finds limit on evaporation to ice sheets, but that may change

CORVALLIS, Ore. – Although the coastal regions of the Greenland Ice Sheet are experiencing rapid melting, a significant portion of the interior of that ice sheet has remained stable – but a new study suggests that stability may not continue.

Researchers found that very little of the snow and ice on the vast interior of the ice sheet is lost to the atmosphere through evaporation because of a strong thermal “lid” that essentially traps the moisture and returns it to the surface where it refreezes.

However, there are signs that this lid is becoming leaky as global temperatures increase. The researchers say there may be a threshold at which warming becomes sufficient to turn on a switch that will destabilize the snow surface.

Results of the study, which was funded by the National Science Foundation, are being published in Science Advances. New measurements from a research tower atop the Greenland ice sheet helped uncovered the mystery of how much snow piles up on this ice sheet.

“Normally, the air temperature goes down as you climb, but near the surface in Greenland, it gets warmer,” said David Noone, an Oregon State University professor who is an atmospheric scientist and principal investigator on the study. “The surface is very cold, but it can be as much as 20 degrees warmer just 30 to 40 feet up in the air. It’s enough that you can feel the difference between your nose and your toes.”

“The temperature difference effectively forms a lid so that there is hardly any evaporation. Warm air likes to rise, but if it is already warmer up above the air is trapped nearer the ground. One consequence is that layers of fog form from water that had recently evaporated. Eventually the small fog water-drops drift back down to the very cold surface where it refreezes onto the ice sheet.”

“It’s a handy little trick of nature.”

Max Berkelhammer, a researcher at the University of Illinois and lead author on the study, said scientists have been aware of “accumulation zones” in high-altitude areas of the ice sheet, but they haven’t been comprehensively measured because of the difficulty in analyzing evaporation and condensation over time.

“Instruments capable of doing this are pretty new and while they have been used before on the ice sheet, they have never been able to run during an entire winter,” said Berkelhammer, who did his post-doctoral work with Noone when both were at the University of Colorado. “I think at this point we are still the only group who has been able to run this type of instrument for an entire year on top of an ice sheet.”

The research aims to better understand how ice cores capture information about past temperatures in Greenland. The snow and ice on Greenland’s interior originated from ocean water far to the south and is transported northward by weather systems and storms, and finally falls as snow on the pristine ice sheet.

The researchers are able to track the origins and fate of the water by the ratio of oxygen and hydrogen isotopes in the water.

Variations in the isotope ratios in layers of snow piled up on the ice sheet provide the team a history of Green climate that helps put recent warming into historical context, the researchers say.

To understand past climate, scientists must know how much precipitation fell and how much evaporated. Without the team’s analysis, what fraction of falling snow accumulates and what fraction evaporates was difficult to determine. When they began to explore evaporation rates, they discovered this unique thermal lid, which effectively “recycles” water back onto the Greenland Ice Sheet.

This finding will allow previous estimates of Greenland’s past water balance to be re-evaluated.

“When thinking about climate change, one often thinks about rising global temperatures,” Noone said. “However in Greenland, as like here in Oregon, climate change is also a story of the changing water cycle and how we lose water because evaporation rates are increasing.

“Climate models suggest that as temperatures increase, more precipitation may actually fall in Greenland because warmer air can hold more water. Taken by itself, that could indicate that parts of the ice sheet may grow. However, if the lid becomes increasingly leaky, the evaporation process has become more effective and moisture will escape to the atmosphere.

“The fate of the ice sheet is in the balance,” Noone said. “It becomes a question of which influence is stronger.”

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David Noone, 541-737-3629, dcn@coas.oregonstate.edu

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This photo of fogbows can be downloaded at: https://flic.kr/p/FM1utW

 

 

 

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Summit Station in Greenland

 

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David Noone, OSU, in a snow pit.

 

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Max Berkelhammer measures ice crystals

OSU to issue RFI on ship project after design completion

CORVALLIS, Ore. – The design phase for a project to construct a new regional class research vessel to replenish the United States academic fleet is complete and Oregon State University will issue a request for information (RFI) on Monday, May 2, to shipyards that may be interested in the vessel construction phase.

In January 2013, the National Science Foundation selected Oregon State as the lead institution to finalize the design and coordinate the construction of the vessel – and possibly up to two more – a project considered crucial to maintaining the country’s marine science research capabilities.

The design phase has been completed by The Glosten Associates, a naval architecture firm based in Seattle, and the RFI is a chance to generate market interest and to get feedback from industry on the design and other project documents. OSU plans to issue a Request for Proposals (RFP) in two phases beginning this summer – a technical phase to establish a competitive pool of qualified shipyards and a cost phase to elicit vessel cost proposals.

“The Request for Information issued on May 2 is a chance for us to make final tweaks in the preliminary design and to open up a dialogue with industry about the project,” said Demian Bailey, Oregon State University’s former marine superintendent and a co-leader on the project. “Once we issue the RFP this summer, it will become more difficult to alter the design or other project documents.”

Although similar in size, the new ship will differ greatly from the R/V Oceanus, built in 1975 and operated by OSU, and its sister ships, Endeavor, operated by the University of Rhode Island, and Wecoma (retired), according to Clare Reimers, a professor in the College of Earth, Ocean, and Atmospheric Sciences and project co-leader.

“This class of ships will enable researchers to work much more efficiently at sea because of better handling and stability, more capacity for instrumentation and less noise,” Reimers said. “The design also has numerous ‘green’ features, including an optimized hull form, waste heat recovery, LED lighting, and variable speed power generation.”

These “regional class research vessels” are designed for studying coastal waters out to beyond the continental rise as part of the U.S. academic fleet that is available to all ocean scientists conducting federal and state-funded research and educational programs.

Among the design features:

  • Each regional class research vessel will be 193 feet, with a range of 7,064 nautical miles;
  • Cruising speed is 11 knots with a maximum speed of 13 knots;
  • There are 16 berths for scientists and 13 for crew members;
  • The ships can stay out at sea for 21 days before coming back to port.

The 2017 President’s budget calls for building two RCRVs, but until a final budget is passed by Congress the plan is to make ready a shipyard contract to build one RCRV with options for additional vessels.

After reviewing the proposals from industry, OSU will select a shipyard in early 2017. The NSF will assume ownership of the regional class research vessels, but Oregon State expects to operate the first vessel constructed, which will conduct science missions primarily in the eastern North Pacific Ocean basin.

Additional vessels would be operated in the Atlantic and Gulf regions of the U.S. by other institutions that the NSF would select in late 2017.

“These ships will also have the ability to operate near ice and are considered ‘ice classed,’ although they are not ice-breakers,” Bailey said. The first ship will likely be delivered in 2020.

More information about the project, including renderings, is available at: http://ceoas.oregonstate.edu/ships/rcrv/

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Demian Bailey, 541-737-0460, dbailey@coas.oregonstate.edu;

Clare Reimers, 541-737-2426, creimers@coas.oregonstate.edu

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This image of the ship is available at: https://flic.kr/p/FGRCR8

Vitamin E protects critical nutrient, prevents neurologic damage and death in embryos

CORVALLIS, Ore. – Researchers have discovered that a dietary deficiency of vitamin E in laboratory animals can cause significant neurological impairment in developing embryos, as well as physical abnormalities and embryonic death.

The study suggests that one mechanism leading to this damage may be loss of the role vitamin E plays in protecting levels of DHA, one of the most important of the omega-3 fatty acids that plays a crucial role in brain and cellular development.

The work, by scientists in the Linus Pauling Institute at Oregon State University, was done with zebrafish, a vertebrate that has neurologic development very similar to humans. They also have dietary needs that are more similar to humans than some other animal models.

In these fish, vitamin E-deficient embryos did not respond correctly to visual cues, had severe physical abnormalities as early as two days after fertilization, and many died before the end of five days.

The findings were published in Redox Biology, in work supported by the National Institutes of Health and the National Science Foundation.

They take on special significance, researchers say, because more than 90 percent of the adults in the United States who do not take supplements have diets deficient in vitamin E.

“DHA in a developing embryo is very important for cell signaling and membrane development,” said Melissa McDougall, an OSU graduate research assistant in the Linus Pauling Institute and the College of Public Health and Human Sciences, and lead author on this publication.

“Our research showed that adequate levels of vitamin E are important in preventing depletion of DHA in the embryo.

“Without enough DHA, there was also evidence for disruption of the structural integrity of cell membranes as a whole. It appears that vitamin E protects these critical lipids, such as DHA, from excessive depletion that can cause physical and behavioral damage.”

The study showed loss of locomotor activity in vitamin E-deficient embryos as a measure of impaired behavior. Vitamin E-deficient embryos were 82 percent less responsive to a light/dark stimulus.

Past research done elsewhere with rodents, McDougall said, has correlated low DHA levels with less memory and intelligence, and one study in Bangladesh with vitamin E-deficient pregnant women showed a higher level of miscarriage.

The recommended daily allowance of vitamin E for human adults is 15 milligrams a day, and the typical American diet rarely provides that. Vitamin E is most common in nuts, seeds, some leafy greens like spinach, and a few varieties of vegetable oils like sunflower and canola. Low-fat diets also present a special challenge in getting enough vitamin E.

Not all pre-natal vitamins even include vitamin E, McDougall said, although some of the better ones are now including not only vitamin E but also supplements of DHA, a nutrient most common in fatty fish. It’s worth noting, she said, that vitamin E cannot serve its role in protecting DHA if there is inadequate dietary DHA to begin with.

Most human brain development occurs during pregnancy, and some of the most important neurologic development happens during the first trimester.

The corresponding author on this publication was Maret Traber, the Helen P. Rumbel Professor for Micronutrient Research in the Linus Pauling Institute. Other collaborators were from the OSU College of Pharmacy, the Sinnhuber Aquatic Research Laboratory, the OSU Department of Environmental and Molecular Toxicology, and the OSU Environmental Health Sciences Center.

 

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Maret Traber, 541-737-7977

maret.traber@oregonstate.edu

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Zebrafish
Zebrafish

Xanthohumol in lab tests lowers cholesterol, blood sugar and weight gain

CORVALLIS, Ore. – A recent study at Oregon State University has identified specific intake levels of xanthohumol, a natural flavonoid found in hops, that significantly improved some of the underlying markers of metabolic syndrome in laboratory animals and also reduced weight gain.

The findings were published in a special issue of Archives of Biochemistry and Biophysics that was focused on “Polyphenols and Health,” and they suggest a possible new approach to issues such as human obesity, high cholesterol and elevated glucose.

Combinations of these problems, collectively known as metabolic syndrome, are linked to some of the major health issues and causes of death in the developed world today - especially cardiovascular disease and type-2 diabetes.

In this research, laboratory mice were fed a high-fat diet, and given varying levels of xanthohumol. Compared to animals given none of this supplement, the highest dosage of xanthohumol given to laboratory rats cut their LDL, or “bad” cholesterol 80 percent; their insulin level 42 percent; and their level of IL-6, a biomarker of inflammation, 78 percent.

Because they were still growing, eating a rich diet, gaining weight and becoming obese, the weight of the lab animals increased, but by 22 percent less in those receiving xanthohumol, even though all animals ate the same amount of food. Intake of xanthohumol appears to increase their oxygen consumption and metabolic rate, with implications for weight control.

“This is the first time we’ve seen one compound with the potential to address so many health problems,” said Cristobal Miranda, a research assistant professor with OSU’s Linus Pauling Institute and lead author on this study. “These were very dramatic improvements.”

More research will be required to show safety and efficacy in humans, the researchers said.

“Work is still needed to further demonstrate the safety of high doses of xanthohumol, but dosages 15-30 times higher than we used have already been given to animals with no apparent problems,” said Fred Stevens, a professor in the OSU College of Pharmacy, principal investigator with the Linus Pauling Institute, and corresponding author on the research.

“After further study, this might provide an effective treatment for metabolic syndrome at a very low cost.”

This study for the first time also identified one of the mechanisms of action of xanthohumol – it appears to decrease plasma levels of PCSK9, a protein that plays a role in cholesterol levels. Lowering levels of PCSK9 should increase the clearance of LDL cholesterol from the blood.

Metabolic syndrome is defined by clinical diagnosis of three or more of several conditions, including abdominal obesity, elevated lipids, high blood pressure, pro-inflammatory state, a pro-thrombotic state, and insulin resistance or impaired glucose tolerance. About 25-34 percent of the adults in the United States meet these criteria, putting them at significantly increased risk for cardiovascular disease and type-2 diabetes.

Direct health care costs arising from obesity or related disorders account for up to 10 percent of U.S. health care expenditures, the researchers noted in their study.

Xanthohumol has been the subject of considerable research for its potential health benefits, as have other flavonoids such as those found in tea, garlic, chocolate, apples and blueberries.

Xanthohumol is found naturally in hops and beer, but the highest level used in this research was 60 milligrams per kilogram of body weight per day. This corresponds to a human equivalent dose of 350 milligrams per day for a 70-kilogram person, which far exceeds any amount that could be obtained by ordinary dietary intake. A level that high would equate to a beer intake of 3,500 pints per day for a human adult.

However, that amount of xanthohumol could readily be obtained in a dietary supplement that could be taken once a day.

This work was supported by the Linus Pauling Institute; OSU College of Pharmacy; Hop Steiner, Inc.; the Buhler-Wang Research Fund; and the National Institutes of Health.

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Cristobal Miranda, 541-737-5512

cristobal.miranda@oregonstate.edu

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Artery disease

Atherosclerosis

Study finds lack of diversity among fisheries scientists

CORVALLIS, Ore. – Researchers who study fish put a high value on biodiversity in the field, yet a new study found a surprising lack of diversity among fisheries scientists themselves.

According to the 2010 United States Census, 51 percent of the people in the U.S. are women. That same year, a study of Ph.D. students in the biological sciences documented that 52 percent of the students pursuing doctorates were women – roughly the same percentage.

However, the new study by researchers at Oregon State University and the U.S. Forest Service found that roughly even split soon disappears – in both federal government positions and in academic institutions. The researchers found that 74 percent of federal fisheries scientists or managers are men, as were 73 percent of the university assistant professors, 71 percent of associate professors and 85 percent of full professors.

The lack of diversity is even more pronounced when analyzed by race. In 2010, the U.S. population was 64 percent white, and participation in biological sciences Ph.D. programs was 69 percent white. Yet only roughly 10 percent of all fisheries science, manager and faculty positions were occupied by minorities.

Results of the study are being published this week in the journal Bioscience.

“It is clear that the fisheries science culture is one dominated by white men,” said Ivan Arismendi, an Oregon State University research faculty scientist and lead author on the study.  “There has been a lot of concern expressed in recent years about diversity, but the numbers don’t seem to reflect that concern. It is important to begin turning the process today because the hiring we’re doing now will last a generation.”

Brooke Penaluna, a research fish biologist with the U.S. Forest Service’s Pacific Northwest Research Station and co-author on the study, said the reasons for the disparity are not completely clear.

“We are graduating women on a 50-50 basis in the biological sciences, but the hiring rate is not keeping pace with the degree rate,” Penaluna said. “For some women, it may be the biological clock butting up against the timetable of career advancement. That doesn’t explain the disparity among minorities.

“We need to look more closely at possible institutional biases. Women, for example, have fewer professional publications and are not asked as often by senior-level scientists to publish. And some federal positions may be in geographic locations that are not attractive to all candidates. We need to create environments that are welcoming so people want to stay – and those conversations can be uncomfortable.”

The authors suggest diversity training and a diverse composition of search committees at both the federal and academic institution levels, as well as increasing the pool of female and minority candidates, and programs to insure their success and career advancement.

At Oregon State University, 28 percent of faculty members in fisheries science are women and 16 percent are non-white.  In December of 2015, OSU named Selina Heppell as head of the Department of Fisheries and Wildlife, the first female to lead the unit in its 80-year history.

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Sources: Ivan Arismendi, 541-750-7443, ivan.arismendi@oregonstate.edu;

Brooke Penaluna, 541-758-8783, brooke.penaluna@oregonstate.edu

Study shows forest thinning changes movement patterns, habitat use by martens

CORVALLIS, Ore. – Scientists who for the first time used global positioning system (GPS) telemetry to monitor the movements of reclusive Pacific martens have discovered that these fierce, tiny mammals tend to avoid open stands of trees resulting from forest thinning.

That could put conservation efforts to protect martens at odds with modern forest management, but the researchers say there is a prescription that may work for both interests: maintaining forest thinning at lower elevations, which are less favored by martens, and preserve more high-elevation forests – which are at less risk for catastrophic wildfire – as complex, marten-friendly stands.

Results of the research, which was conducted in northern California, have just been published in the Journal of Wildlife Management.

“There are two main reasons that martens avoid open forests,” said Katie Moriarty, a post-doctoral research biologist with the U.S. Forest Service, who conducted the research as a doctoral student at Oregon State University. “Martens eat a lot of food – up to a quarter of their body weight a day. It would be like you eating 100 hamburgers. They need downed logs and dense sapling cover to hunt successfully.

“Since they are the size of a gray squirrel, the woods are a dangerous place. They need to avoid being eaten. And for them, a wide-open forest is like being dropped into Jurassic Park filled with velociraptors. They just won’t stay in those areas.”

The study is important because Pacific martens are considered an indicator species for ecosystem health, said Clinton Epps, an associate professor in OSU’s Department of Fisheries and Wildlife and co-author on the study. The key to the research was the use of GPS to observe a finer scale of the martens’ movements.

“We were able to collect the locations of tagged martens so frequently that we could infer their movements through tree stands rather than relying on a typical radio telemetry study,” Epps said. “There was clear evidence that their movement is affected by forest characteristics in different seasons.

“The spatial configuration of habitat is very important in these systems, even at the scale of an individual animal’s movement. The martens typically avoided simplified stands and they behaved differently if they used them.”

Much of the research was conducted in Lassen National Forest, which has the lowest documented annual survival rates for martens in North America – about 37 percent of them die each year. Forest lands are actively thinned, Moriarty said, although there is no established link between the survival rate and forest management practices. “We can’t assume a causal relationship,” she said.

What the researchers can document is how martens move through different forest types.

“Martens strongly selected complex forest stands over simple stands and openings,” said Moriarty, who is with the Forest Service’s Pacific Northwest Research Station in Olympia, Washington. “Their movements were slower and more sinuous in complex stands with lots of cover. When they were in the open, their movements were more erratic and linear. Those altered patterns of movement in open forests appear to negatively affect the ability of martens to forage without increase risk of predation.”

Martens are one of the smaller members of the weasel family, weighing between one and two-and-a-half pounds – and they look something like a cross between a fox and a mink. Martens are “smaller than a Chihuahua,” Moriarty said, “but have the attitude of a pit bull. They really have a little man’s complex.”

Small but fierce predators, martens feast on snowshoe hare, chipmunks, voles and other small mammals, and also consume bird eggs and berries. They can survive rugged winters with snow more than a dozen feet deep.

“If martens are thriving in an area, that usually is a sign of a healthy ecosystem,” Moriarty said.

Moriarty’s work has paid off in more than one way. In 2008, while studying martens in Tahoe National Forest, she gathered photographic evidence of a wolverine – the first sighting of the animal in California in 75 years.

The marten research was funded by Lassen National Forest with assistance from the Pacific Southwest Research Station and OSU’s Department of Fisheries and Wildlife.

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Katie Moriarty, 360-753-7716, kmoriarty02@fs.fed.us;

Clint Epps, 541-737-2478, Clinton.epps@oregonstate.edu

West Coast scientists sound alarm for changing ocean chemistry

CORVALLIS, Ore. – The ocean chemistry along the West Coast of North America is changing rapidly because of global carbon dioxide emissions, and the governments of Oregon, California, Washington and British Columbia can take actions now to offset and mitigate the effects of these changes.

That is the conclusion of a 20-member panel of leading West Coast ocean scientists, who presented a comprehensive report on Monday outlining a series of recommendations to address the increase in ocean acidification and hypoxia, or extremely low oxygen levels.

“Ocean acidification is a global problem that is having a disproportionate impact on productive West Coast ecosystems,” said Francis Chan, an Oregon State University marine ecologist and co-chair of the West Coast Ocean Acidification and Hypoxia Science Panel. “There has been an attitude that there is not much we can do about this locally, but that just isn’t true. A lot of the solutions will come locally and through coordinated regional efforts.”

Ocean acidification and hypoxia are distinct phenomena that trigger a wide range of effects on marine ecosystems. They frequently occur together and represent two important facets of global ocean changes that have important implications for Oregon’s coastal oceans.

Among the panel’s recommendations:

  • Develop new benchmarks for near-shore water quality as existing criteria were not developed to protect marine organisms from acidification;
  • Improve methods of removing carbon dioxide from seawater through the use of kelp beds, eel grass and other plants;
  • Enhance coastal ecosystems’ ability to adapt to changing ocean chemistry through better resource management, including marine reserves, adaptive breeding techniques for shellfish, and other methods.

“Communities around the country are increasingly vulnerable to ocean acidification and long-term environmental changes," said Richard Spinrad, chief scientist for the National Oceanic and Atmospheric Administration, and former OSU vice president for research. “It is crucial that we comprehend how ocean chemistry is changing in different places, so we applaud the steps the West Coast Ocean Acidification and Hypoxia Science Panel has put forward in understanding and addressing this issue. We continue to look to the West Coast as a leader on understanding ocean acidification.”

Chan said regional awareness of the impact of changing ocean chemistry started in Oregon. Some of the first impacts were seen about 15 years ago when the state began experiencing seasonal hypoxia, or low-oxygen water, leading to some marine organism die-offs. Then the oyster industry was confronted with high mortality rates of juvenile oysters because of increasingly acidified water. It turns out that Oregon was on the leading edge of a much larger problem.

“It was a wakeup call for the region, which since has spread up and down the coast,” said Chan, an associate professor in the Department of Integrative Biology in OSU’s College of Science.

California responded to this call, and in partnership with Oregon, Washington and British Columbia, convened a panel of scientific experts to provide advice on the issue. The panel worked with federal and state agencies, local organizations and higher education institutions to identify concerns about ocean acidification and hypoxia, then developed a series of recommendations and actions that can be taken today.

“One of the things all of the scientists agree on is the need for better ocean monitoring or ‘listening posts,’ up and down the West Coast,” said Jack Barth, a professor and associate dean in OSU’s College of Earth, Ocean, and Atmospheric Sciences and a member of the panel. “It is a unifying issue that will require participation from state and federal agencies, as well as universities, ports, local governments and NGOs.”

Barth said one such “listening post” has been the Whiskey Creek Shellfish Hatchery in Netarts Bay, Oregon, which was able to solve the die-off of juvenile oysters with the help of OSU scientists George Waldbusser and Burke Hales, who both served on the 20-member panel. Together, they determined that the ocean chemistry changed throughout the day and by taking in seawater in the afternoon, when photosynthesis peaked and CO2 levels were lower, juvenile oysters could survive.

The West Coast is a hotspot for acidification because of coastal upwelling, which brings nutrient-rich, low-oxygen and high carbon dioxide water from deep in the water column to the surface near the coast. These nutrients fertilize the water column, trigger phytoplankton blooms that die and sink to the bottom, producing even more carbon dioxide and lowering oxygen further.

“We’re just starting to see the impacts now, and we need to accelerate what we know about how increasingly acidified water will impact our ecosystems,” said panel member Waldo Wakefield, a research fisheries biologist with NOAA Fisheries in Newport and courtesy associate professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences.

“There’s a lot at stake. West Coast fisheries are economic drivers of many coastal communities, and the seafood we enjoy depends on a food web that is likely to be affected by more corrosive water.”

Last year, OSU researchers completed the deployment of moorings, buoys and gliders as part of the Endurance Array – a component of the $386 million National Science Foundation-funded Ocean Observatories Initiative, created to address ocean issues including acidification.

These and other ocean-monitoring efforts will be important to inform policy-makers about where to best focus their adaptation and mitigation strategies.

“The panel’s findings provide a road map to help us prepare for the changes ahead,” said Gabriela Goldfarb, natural resource policy adviser to Oregon Gov. Kate Brown. “How Oregon and the West Coast address ocean acidification will inform those confronting this issue around the country and world.”

“With the best scientific recommendations in hand from the science panel, we now have the information on which to base our future management decisions,” added Caren Braby, marine resource manager at the Oregon Department of Fish and Wildlife. “These are practical recommendations natural resource managers and communities can use to ensure we continue to have the rich and productive ecosystem Oregonians depend on for healthy fisheries, our coastal culture and economy.”

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Francis Chan, 541-844-8415, chanft@science.oregonstate.edu;

Jack Barth, 541-737-1607, barth@coas.oregonstate.edu

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An oyster at Whiskey Creek Shellfish Hatchery

“Community solar” systems may add savings to local, cooperative energy projects

CORVALLIS, Ore. – Part of the future of solar energy, especially for residential use, may be small “community-based” systems in which neighbors join together in the construction and use of solar systems to optimize the energy produced in their neighborhood – and share in the benefits.

New research by engineers at Oregon State University indicate that an optimal development of neighborhood solar energy might increase the total electricity produced by 5-10 percent, a significant gain by the standards of solar energy efficiency. At the same time, it can reduce the variability and unpredictability of the solar resource.

With this approach, the use of various rooftops and land used for solar energy production may vary from house to house, depending upon such issues as the home’s orientation, roof slope and shading from trees or other structures. Quite simply, some structures lend themselves better than others to solar energy.

“An approach such as this makes the most sense in a neighborhood where there’s a lot of variation in terms of sun and shadow, and the orientation of buildings,” said Mahmoud Shakouri, a doctoral candidate in the OSU College of Engineering.

“The conventional approach to residential solar energy is to look at each home as an individual package, building its own solar system whether or not that’s a good location. But by grouping 10 or 20 houses in a neighborhood, all of whose owners are interested in solar energy, we can optimize the use and placement of solar panels and let everyone share in the savings.”

The idea has been considered for some time, Shakouri said, but failed to generate much headway in the United States due to limited interest in solar energy, high initial costs, and tax credits or incentives that fail to recognize this approach to optimizing the solar resource.

Findings on this issue have been published recently in the journals of Applied Energy and Data in Brief, and a “decision support model” has been created that homeowners could use to help consider the best options for their neighborhood. Free software to help implement such a strategy is also available from the U.S. Department of Energy. Collaborating on this research was Hyun Woo Lee at the University of Washington.

Initial solar installations can be expensive, making it all the more important to maximize the long-term output of the systems. But such systems are also durable and pollution free, usually with a performance guarantee of up to 25 years, using a technology that produces no greenhouse gases.

Residential energy use is also a big-ticket item – in the United States, the building sector accounts for 40 percent of total energy consumption, and residential buildings consume more than half of the energy in the building sector. By 2035, the federal government estimates that 74 percent of the energy consumed in residences will be in the form of electricity, even as two thirds of the nation’s electricity is still produced by coal or natural gas that are helping to cause global warming.

The new approach developed at OSU, Shakouri said, actually borrows formulas from economic theory. This approach has long been used in the stock market in the form of portfolio investment, to maximize profit while reducing risks. Given the high initial cost of some solar systems – averaging about $20,000 for a 4 kilowatt residential system – reducing risk is of considerable value to many people interested in the technology.

Studies done at OSU included a case study of collaborative solar energy among 24 homes in a neighborhood in Corvallis, Ore., which has sunny summers but often-cloudy and rainy winters, not exactly the nation’s best bet in terms of solar energy production. Even there, this approach increased the annual electricity output of the homes by 4.6 percent and reduced the volatility in electrical output by 4.3 percent.

Use of approaches such as this may become more common as the efficiency of solar technology improves, more people become aware of its potential, and legislation or policies are changed to better enable community solar projects, researchers say. More work is also needed to determine how to contractually share expenses, profits and benefits among cooperating neighbors.

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Mahmoud Shakouri

shakourm@oregonstate.edu

 

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