OREGON STATE UNIVERSITY

scientific research and advances

OSU researchers fix calculation error in study on fracking and human health

CORVALLIS, Ore. – A 2015 Oregon State University study that linked natural-gas fracking to increased air pollution and heightened health risks has been corrected by its authors.

The corrected article still concludes that natural gas extraction contributes polluting chemicals known as polycyclic aromatic hydrocarbons (PAHs) to the air, but at levels that would not be expected to increase lifetime cancer risk above the EPA threshold.

The researchers measured levels of airborne PAHs near several Ohio hydraulic-fracturing sites in 2014. PAHs have been linked to increased risk of cancer and respiratory diseases.

In their March 2015 article, published in the journal Environmental Science and Technology, the researchers reported that PAH pollution from fracking could put a person living in the study area at a greater than a one-in-a-million risk of developing cancer during his or her life. One in a million is the threshold set by the U.S. Environmental Protection Agency for unacceptable cancer risk.

The authors retracted the article on June 29, 2016, after they found an error in a complicated spreadsheet used to calculate the concentrations of various PAH chemicals in the air.

The researchers redid the calculations and submitted a corrected version of the article, which was published on July 11, 2016. It finds that the estimated risk for the maximum exposure to fracking-related PAH pollution in the study area is 0.04 in a million—well below the EPA’s threshold.

Steve Clark, OSU’s vice president for university relations, said the mistake came to light as the researchers were crunching numbers from a current project. In the process, he said, they discovered a similar calculation error in a 2014 study of PAH pollution of air and water during the 2010 Deepwater Horizon oil spill, which also was published in Environmental Science and Technology.

That article too was retracted on June 29, and the corrected article was published online on July 8.

“In both cases the researchers were using a complicated, multi-linked spreadsheet to analyze large quantities of data,” said Clark. “The error was an honest mistake that unfortunately slipped through the peer-review process. Our researchers knew they couldn’t let it stand, so they stepped forward and corrected the error.”  

The coauthors of the Ohio fracking study include OSU researchers Kim Anderson (College of Agricultural Sciences) and Laurel Kincl (College of Public Health and Human Sciences), and Erin Haynes of the University of Cincinnati. Anderson also coauthored the Deepwater Horizon study.

Story By: 
Source: 

Terrifed insect escapes a permanent tomb – 50 million years ago

CORVALLIS, Ore. – Thousands of insects, plants and other life forms have been found trapped in ancient amber deposits, but a new discovery shows a rarity of a different type – the one that got away.

In a piece of Baltic amber about 50 million years old, research has uncovered an exoskeleton similar to that of a modern-day “walking stick” – evidence of an insect that literally was frightened out of its skin, and made its way to freedom just as it was about to become forever entombed by oozing tree sap.

The unusual piece also reveals the first mushroom that’s ever been found in Baltic amber, along with a mammalian hair that was left behind. In its entirety, the amber piece offers a little docudrama of life, fear and hasty escape in the ecology of an ancient subtropical forest.

The findings were just published in Fungal Biology by George Poinar, Jr., a researcher in in the College of Science at Oregon State University and an international expert in ancient life forms found in amber.

“From what we can see in this fossil, a tiny mushroom was bitten off, probably by a rodent, at the base of a tree,” Poinar said. “An insect, similar to a walking stick, was probably also trying to feed on the mushroom. It appears to have immediately jumped out of its skin and escaped, just as tree sap flowed over the remaining exoskeleton and a hair left behind by the fleeing rodent.”

Plants, insects and other material found in amber deposits, Poinar said, always offer details about ancient ecosystems. But on rare occasions such as this, they also show the interactions and ecology between different life forms. They are invaluable in helping scientists to reconstruct the nature of ecosystems in the distant past.

In this case, the amber came from near the Baltic Sea in what’s now Germany, Poland, Russia and Scandinavia. It was formed, beginning as a viscous tree sap, in a large subtropical coniferous forest across much of northern Europe that lasted about 10 million years.

In a climate much warmer than exists there today, the early angiosperms, or flowering plants, were starting to displace the gymnosperms, or cone-bearing evergreens that had previously been dominant. Dinosaurs had gone extinct a few million years before, and mammals were beginning to diversify.

“The tiny insect in this fossil was a phasmid, one of the kinds of insects that uses its shape to resemble sticks or leaves as a type of camouflage,” Poinar said.

“It would have shed its skin repeatedly before reaching adulthood, in a short lifespan of a couple months. In this case, the ability to quickly get out of its skin, along with being smart enough to see a problem coming, saved its life.”

The exoskeleton seen in the amber is extremely fresh and shows filaments that would have disappeared if it had been shed very long before being covered by amber, Poinar said.

This particular insect species is now extinct, as is the mushroom in the fossil, Poinar said. Although mushrooms have been found in fossils from other regions of the world, this is the first specimen to be identified in Baltic amber, and represents both a new genus and species.

The Baltic amber deposits are the largest in the world, have been famous for thousands of years and continue to be mined today. Amber from the mines were traded by Roman caravans, later taken over by Teutonic knights and are known around the world for the huge volume of semi-precious stones they produce.

Story By: 
Source: 

George Poinar, Jr.

poinarg@science.oregonstate.edu

Multimedia Downloads
Multimedia: 

Narrow escape
Insect escapes

Pacific Storm operations transferred to OSU college

NEWPORT, Ore. – Operations of the 85-foot-long Oregon State University research vessel Pacific Storm have been transferred from the Marine Mammal Institute at OSU to the university’s College of Earth, Ocean, and Atmospheric Sciences (CEOAS).

The transfer will put the university’s three major research vessels under the same unit; CEOAS also operates the 177-foot R/V Oceanus and the 54-foot R/V Elakha.

The transfer will make the Pacific Storm available for year-round cruises – weather permitting – and improve access to the sea for OSU scientists, students and collaborators across the university, said Bruce Mate, director of OSU’s Marine Mammal Institute.

“The Pacific Storm has been a great vessel for us, but it makes more sense logistically to operate all the vessels under a single unit,” Mate said. “We’ll continue to use the ‘Storm’ but this will allow many other researchers access to her.”

In the past decade, the R/V Pacific Storm has hosted 52 cruises, including one that culminated in the National Geographic documentary, “Kingdom of the Blue Whale,” which featured Mate’s research on the largest animals to have ever lived on Earth. The vessel has been used for a variety of whale research, as well as to deploy wave energy buoys, conduct seafloor mapping off the Oregon Coast, and deploy and recover undersea gliders.

The Pacific Storm originally was a commercial trawler that was donated to the OSU Marine Mammal Institute by Scotty and Janet Hockema, and refitted for research. The fish hold was converted into three bunk rooms, two toilets and a shower, and the vessel was outfitted with a research laboratory. Private donations paid for the refitting of the $1.5 million vessel.

The Pacific Storm will be housed and operated by OSU Ship Operations at the university’s Hatfield Marine Science Center in Newport, said Stewart Lamerdin, OSU’s marine superintendent.

“As the university moves forward with its Marine Studies Initiative, there will be an increasing demand for access by students and scientists to research vessels,” Lamerdin said. “Managing all three vessels in a single operation will help OSU maximize their usage.”

Story By: 
Source: 

Bruce Mate, 541-867-0202, bruce.mate@oregonstate.edu;

Stewart Lamerdin, 541-867-0225, slamerdin@coas.oregonstate.edu

Multimedia Downloads
Multimedia: 

 

 

This photo is available at: https://flic.kr/p/9VCUfV

New technology could improve use of small-scale hydropower in developing nations

CORVALLIS, Ore. – Engineers at Oregon State University have created a new computer modeling package that people anywhere in the world could use to assess the potential of a stream for small-scale, “run of river” hydropower, an option to produce electricity that’s of special importance in the developing world.

The system is easy to use; does not require data that is often unavailable in foreign countries or remote locations; and can consider hydropower potential not only now, but in the future as projected changes in climate and stream runoff occur.

OSU experts say that people, agencies or communities interested in the potential for small-scale hydropower development can much more easily and accurately assess whether it would meet their current and future energy needs.

Findings on the new assessment tool have been published in Renewable Energy, in work supported by the National Science Foundation.

“These types of run-of-river hydropower developments have a special value in some remote, mountainous regions where electricity is often scarce or unavailable,” said Kendra Sharp, the Richard and Gretchen Evans Professor in Humanitarian Engineering in the OSU College of Engineering.

“There are parts of northern Pakistan, for instance, where about half of rural homes don’t have access to electricity, and systems such as this are one of the few affordable ways to produce it. The strength of this system is that it will be simple for people to use, and it’s pretty accurate even though it can work with limited data on the ground.”

The new technology was field-tested at a 5-megawatt small-scale hydropower facility built in the early 1980s on Falls Creek in the central Oregon Cascade Range. At that site, it projected that future climate changes will shift its optimal electricity production from spring to winter and that annual hydropower potential will slightly decrease from the conditions that prevailed from 1980-2010.

Small-scale hydropower, researchers say, continues to be popular because it can be developed with fairly basic and cost-competitive technology, and does not require large dams or reservoirs to function. Although all forms of power have some environmental effects, this approach has less impact on fisheries or stream ecosystems than major hydroelectric dams. Hydroelectric power is also renewable and does not contribute to greenhouse gas emissions.

One of the most basic approaches is diverting part of a stream into a holding basin, which contains a self-cleaning screen that prevents larger debris, insects, fish and objects from entering the system. The diverted water is then channeled to and fed through a turbine at a lower elevation before returning the water to the stream.

The technology is influenced by the seasonal variability of stream flow, the “head height,” or distance the water is able to drop, and other factors. Proper regulations to maintain minimum needed stream flow can help mitigate environmental impacts.

Most previous tools used to assess specific sites for their small-scale hydropower potential have not been able to consider the impacts of future changes in weather and climate, OSU researchers said, and are far too dependent on data that is often unavailable in developing nations.

This free, open source software program was developed by Thomas Mosier, who at the time was a graduate student at OSU, in collaboration with Sharp and David Hill, an OSU associate professor of coastal and ocean engineering. It is now available to anyone on request by contacting Kendra.sharp@oregonstate.edu

This system will allow engineers and policy makers to make better decisions about hydropower development and investment, both in the United States and around the world, OSU researchers said in the study.

Story By: 
Source: 

Kendra Sharp, 541-737-5246

kendra.sharp@oregonstate.edu

Multimedia Downloads
Multimedia: 

Small scale hydropower
Small scale hydropower

Oil and gas infrastructure doesn’t seem to deter nesting hawks

CORVALLIS, Ore. -- Roads and petroleum wells in Wyoming’s oil and gas country don’t seem to interfere with the nesting of ferruginous hawks, according to recent findings by Oregon State University wildlife researchers.

In their three-year study, published in the journal PLOS ONE, wildlife biologists Zach Wallace and Patricia Kennedy found that the birds were equally likely to return to nests near energy infrastructure, such as roads and well pads, as to those farther away.

The birds’ nesting choices proved to be influenced more by abundance of prey animals such as ground squirrels, and by relatively sparse sagebrush cover, than by structures associated with oil and gas fields, the researchers concluded.

The study, conducted in collaboration with the U.S. Forest Service and Wyoming Department of Game and Fish, is the largest in the U.S. so far on the impacts of oil and gas development on the federally protected hawks, which are regarded as a “species of conservation concern” by some federal and state agencies.

But it’s too early, Wallace cautioned, to assume that oil and gas activities are benign.

“We don’t have pre-construction data,” he said, “so we were studying birds that had continued to nest after energy exploration began. It is possible that some hawks may already have abandoned the areas of densest development prior to our study.”

Kennedy said the long-term effect of energy development on abundance of prey is unknown.

“We know from the literature that ferruginous hawks can nest in working landscapes,” she said. “But we present our findings with some caution, because we don’t know what the thresholds are,” for habitat changes that will harm the birds’ reproductive success.

“Some prey species seem to thrive under disturbances from oil and gas development; others may not.”

Kennedy is a professor in OSU’s College of Agricultural Sciences stationed at the Eastern Oregon Agricultural Research Center in Union, Ore. Wallace led the study as Kennedy’s master’s student and now works for Eagle Environmental, a conservation consulting firm in New Mexico.

The ferruginous hawk (Buteo regalis) is the largest hawk species in North America. The birds are partially migratory, wintering as far south as central Mexico and returning north in the spring to breeding territories in the arid shrub- and grasslands of the western U.S.

The hawks nest in trees and rocky outcrops, returning to prior years’ nests if these are available. They also nest readily on human-made structures such as artificial nesting platforms, power poles, abandoned windmills, even gas condensation tanks. They will nest on the ground if elevated structures are not present, Kennedy said.

Birds that inhabit grasslands and shrublands are declining around the world primarily because of human-caused disturbances, Wallace said. He and Kennedy undertook the study to determine which of several key influences were most important in the hawks’ reuse of breeding territories and nesting success: abundance of prey, shrub cover, weather, type of nest substrate, and density of human structures such as roads and well pads.

The researchers counted hawk nests from a small airplane over three seasons, and they sampled prey species on the ground. Their study area covered nearly half the state of Wyoming and included both public and private land.

They divided the sampling territory into areas with low, medium and high density of oil and gas infrastructure. After the initial nest count, they monitored the nests during spring breeding season over the next two years to see whether the birds returned to prior years’ nests and how many young they produced.

Based on earlier research, they expected that returning birds would avoid nests within 1.5 kilometers of roads and well pads. Instead, they found that the birds were equally likely to come back to these nests as to the ones farther away.

The findings could affect the mitigation measures required of energy companies to protect wildlife habitat, said Wallace, which are now negotiated with land management authorities on a project-by-project basis.

“One of the strengths of our study is its broad spatial scale, which makes it more relevant to management decisions than the smaller-scale studies that have been done in the past,” he said. “We were able to study these hawks at the scale of their ecology, and also at the scale of oil and gas development.”

Wyoming’s oil and gas industry has grown rapidly since the late 20th century, although growth has slowed lately as prices for fossil fuels have declined.

“We collected an excellent, large dataset on the hawks’ nesting behavior in both disturbed and undisturbed areas,” Wallace said. “This study lays the groundwork for rigorous before-and-after studies if and when oil and gas drilling spreads into now-undeveloped areas.”

Story By: 
Source: 

Patricia Kennedy, 541-562-5129 X 31

pat.kennedy@oregonstate.edu

Multimedia Downloads
Multimedia: 

Ferruginous hawk
Ferruginous hawk

Study finds native Olympia oysters more resilient to ocean acidification

CORVALLIS, Ore. – Native Olympia oysters, which once thrived along the Pacific Northwest coast until over-harvesting and habitat loss all but wiped them out, have a built-in resistance to ocean acidification during a key shell-building phase after spawning, according to a newly published study.

Unlike the commercially raised Pacific oysters, Olympia oysters don’t begin making their shells until 2-3 days after fertilization and make them far more slowly, which helps protect them from corrosive water during this critical development phase, said Oregon State University’s George Waldbusser, principal investigator on the project.

Pacific oysters, on the other hand, only have a six-hour window to develop their calcium carbonate shell, and when exposed to acidified water, their energy stores become depleted. The larval oysters may get through the shell-building stage, Waldbusser said, but they often will not have enough energy to survive.

Results of the study are being published this week in the Journal of Limnology and Oceanography.

“This is a unique trait that allows native oysters to survive surprisingly high levels of acidification,” said Waldbusser, a marine ecologist in OSU’s College of Earth, Ocean, and Atmospheric Sciences. “But they didn’t develop that trait in response to rising acidification. It has been there for some time. It does make you wonder if there may be traits in other organisms that we’re unaware of that may be beneficial.”

In their study, which was funded by the National Science Foundation, the OSU researchers measured the calcification rates of both Olympia and Pacific oysters for five days after spawning, taking measurements every three hours. Although other studies have looked at the effects of acidified water on adult oysters, this is the first time researchers have been able to pinpoint its effect on larval oysters in the shell-building stage.

What they found was a seven-fold difference in the calcification rate. Pacific oysters put all of their energy into rapidly developing a shell, but the price of that investment is huge.

Native Olympia oysters developed their shells much more slowly, but seemingly at a lower cost.

“Pacific oysters churn out tens of millions of eggs, and those eggs are much smaller than those of native oysters even though they eventually become much larger as adults,” Waldbusser said. “Pacific oysters have less energy invested in each offspring. Olympia oysters have more of an initial energy investment from Mom, and can spend more time developing their shells and dealing with acidified water.”

The OSU researchers found that relative energy stores of young Pacific oysters declined by 38.6 percent an hour, and only 0.9 percent in Olympia oysters.

The study noted other interesting differences between Pacific and Olympia oysters. Native Olympia oyster larvae develop in a brood chamber, where the embryos take longer to develop. However, these brood chambers don’t necessarily protect the young oysters from acidified water, since water is continually pumped through the chamber.

To test how the oysters would do when raised like Pacific oysters – outside the chamber – the researchers conducted an experiment raising the larval Olympia oysters outside their brood chamber and exposing them to acidified water.

“Brooding was thought to provide several advantages to developing young, but we found it does not provide any physiological advantage to the larvae,” said Matthew Gray, a former doctoral student in OSU’s Department of Fisheries and Wildlife and now a post-doctoral researcher at the University of Maine. “They did just as well outside the brood chamber as inside.

“Brooding does help guard the larvae from predators and some adverse environmental changes – such as low-salinity events.”

The research highlights this robust response to ocean acidification at this critical life-history stage of Olympia oyster larvae, a period which has not previously been studied. Past studies conducted by Annaliese Hettinger, a post-doctoral researcher in Waldbusser’s lab, found that the Olympia oyster larvae are sensitive to acidification in the later swimming stage, and those effects can carry over to adult stages.

The current research may, however, have implications for the future of the commercial oyster industry, given that many of the problems seem to originate at this very early developmental stage. Cultivation of native oysters could help guard against catastrophic Pacific oyster losses due to acidification, the researchers say, or it may be possible to breed some of the Olympia oysters’ beneficial traits into Pacific oysters – either slowing the calcification rate of early larvae or producing fewer and bigger eggs.

The Olympia oyster, which is smaller than the commercially grown Pacific oyster, is prized for its distinctive flavor. Originally, Olympia oysters grew from Baja California to Vancouver Island, and are found sparingly in three Oregon bays – Yaquina, Netarts and Coos Bay. During the height of these harvests in the 1890s, some 130,000 bushels of oysters were annually shipped from the Pacific Northwest to California and within 20 years, 90 percent of these native oysters had disappeared.

Researchers speculate that the remaining Olympia oyster populations may have succumbed to increased silt generated by 20th-century logging and mill operations, which either killed them outright or covered their beds and destroyed their habitat. They have not returned in discernible numbers to Oregon estuaries.

Story By: 
Source: 

George Waldbusser, 541-737-8964

waldbuss@coas.oregonstate.edu

Multimedia Downloads
Multimedia: 

Olympia oyster cluster

Olympia oysters



Olympia oysters
Olympia oysters
from Yaquina Bay

“Weather@Home” offers precise new insights into climate change in the West

CORVALLIS, Ore. – Tens of thousands of “citizen scientists” have volunteered some use of their personal computer time to help researchers create one of the most detailed, high resolution simulations of weather ever done in the Western United States.

The data, obtained through a project called Weather@Home, is an important step forward for scientifically sound, societally relevant climate science, researchers say in a an article published in the Bulletin of the American Meteorological Society. The analysis covered the years 1960-2009 and future projections of 2030-49.

“When you have 30,000 modern laptop computers at work, you can transcend even what a supercomputer can do,” said Philip Mote, professor and director of the Oregon Climate Change Research Institute at Oregon State University, and lead author on the study.

“With this analysis we have 140,000 one-year simulations that show all of the impacts that mountains, valleys, coasts and other aspects of terrain can have on local weather,” he said. “We can drill into local areas, ask more specific questions about management implications, and understand the physical and biological climate changes in the West in a way never before possible.”

The sheer number of simulations tends to improve accuracy and reduce the uncertainty associated with this type of computer analysis, experts say. The high resolution also makes it possible to better consider the multiple climate forces at work in the West – coastal breezes, fog, cold air in valleys, sunlight being reflected off snow – and vegetation that ranges from wet, coastal rain forests to ice-covered mountains and arid scrublands within a comparatively short distance.

Although more accurate than previous simulations, improvements are still necessary, researchers say. Weather@Home tends to be too cool in a few mountain ranges and too warm in some arid plains, such as the Snake River plain and Columbia plateau, especially in summer. While other models have similar errors, Weather@Home offers the unique capability to improve simulations by improving the physics in the model.

Ultimately, this approach will help improve future predictions of regional climate. The social awareness of these issues has “matured to the point that numerous public agencies, businesses and investors are asking detailed questions about the future impacts of climate change,” the researchers wrote in their report.

This has led to a skyrocketing demand for detailed answers to specific questions – what’s the risk of a flood in a particular area, what will be future wind speeds as wind farms are developed, how should roads and bridges be built to handle extremely intense rainfall?  There will be questions about heat stress on humans, the frequency of droughts, future sea levels and the height of local storm surges.

This type of analysis, and more like it, will help answer some of those questions, researchers say.

New participants in this ongoing research are always welcome, officials said. If interested in participating, anyone can go online to “climateprediction.net” and click on “join.” They should then follow the instructions to download and install BOINC, a program that manages the tasks; create an account; and select a project. Participation in climateprediction.net is available, as well as many others.

The work has been supported by Microsoft Corp., the U.S. Bureau of Land Management, the California Energy Commission, the U.S. Geological Survey and the USDA.

Collaborators on the report were from OSU, Oxford University in the United Kingdom, and the Met Office Hadley Centre in the United Kingdom.

Story By: 
Source: 

Phil Mote, 541-913-2274

pmote@coas.oregonstate.edu

Multimedia Downloads
Multimedia: 

Elevation map
Elevation map

Coral reefs fall victim to overfishing, pollution aggravated by ocean warming

CORVALLIS, Ore. – Coral reefs are declining  around the world because a combination of factors – overfishing, nutrient pollution, and pathogenic disease – ultimately become deadly in the face of higher ocean temperatures, researchers have concluded.

A study published today in Nature Communications, based on one of the largest and longest field experiments done on this topic, suggests that the widespread coral deaths observed in recent decades are being caused by this combination of multiple local stressors and global warming.

These forces greatly weaken corals, and allow opportunistic pathogens to build to such levels that corals cannot survive.

The findings were made by researchers from six institutions following a three-year experiment that simulated both overfishing and nutrient pollution on a coral reef in the Florida Keys. The large body of field data collected over an extended period of time helped resolve some of the fundamental questions about the cause of coral reef declines, scientists said.

“This is grim news, but at least it will help settle the argument over why corals are dying,” said Rebecca Vega Thurber, an assistant professor in the College of Science at Oregon State University and corresponding author on the study.

“This makes it clear there’s no single force that’s causing such widespread coral deaths. Loss of fish that help remove algae, or the addition of excess nutrients like those in fertilizers, can cause algal growth on reefs. This changes the normal microbiota of corals to become more pathogenic, and all of these problems reach critical levels as ocean temperatures warm.”

The end result, scientists say, is a global decline of coral reefs that is now reaching catastrophic proportions.

“We need to know how human activities are affecting coral reef ecosystems,” says David Garrison, program director in the National Science Foundation’s Division of Ocean Sciences, which funded the research.  “Coral reefs are among the most sensitive indicators of the health of the oceans. This report is a major contribution toward understanding how reefs will fare in the future.”

Scientists say the problems caused by bacterial infections due to local stressors and warm temperatures are in addition to damage from mass coral bleaching events already under way. Only in the early 1980’s did researchers observe the first mass bleaching event in recorded history. There have now been three such events just in the past 20 years.

“About 25-35 percent of the corals on the Great Barrier Reef are dying right now,” Vega-Thurber said. “In 2014-16 large portions of tropical reef across the planet experienced bleaching, and this past April, 90 percent of the Great Barrier Reef bleached as part of a massive El Nino event. Corals everywhere seem to be dying.”

In addition to helping to sort out the effects of known stressors like overfishing and nutrient pollution, the researchers made one bizarre and totally unexpected finding.

In normal conditions, parrotfish, like many other species, are essential to the health of coral reefs, nibbling at them to remove algae and causing no permanent damage. But in one part of the experiment corals were so weakened by nitrogen and phosphorus pollution that when parrot fish would bite them, 62 percent of the corals would die. A normally healthy fish-coral interaction had been turned into a deadly one.

“Normally benign predation by the parrotfish turned into coral murder,” said Deron Burkepile, also a corresponding author on the study at the University of California – Santa Barbara. “But it’s not the parrotfishes, they’re like the reef janitors, keeping it clean. Those extra nutrients — nutrient pollution — turn parrotfishes into an actual source of mortality by facilitating pathogens in the wounds left by their bites. Excess nutrients turn a coral accomplice into a coral killer.”

The researchers said they want to make it clear that parrotfish are not the problem, they are an essential part of healthy reef ecosystems.

“The problem is when corals are so weakened they cannot withstand normal impacts,” Vega-Thurber said. “And the solution will be to help those corals recover their health, by ensuring that their local environment is free of nutrient pollution and that fish stocks are not depleted.”

Among the findings of the study:

  • Overfishing, nutrient pollution and increased temperature all lead to an increase in pathogens;
  • The sheer abundance of pathogens is more important than what particular type or species they are;
  • Coral reef mortality mirrors the abundance of pathogens;
  • Heat exacerbates these problems, with 80 percent of coral deaths coming in the summer or fall, but only when fish are removed or nutrient pollution is present;
  • While high thermal stress has received the most attention, even modest temperature increases make corals more vulnerable to bacteria;
  • Loss of fish can increase algal cover up to six times;
  • In a distressed system with many algae, coral disease levels double and coral mortality increases eight times;
  • Increased algal cover or elevated temperature can reduce levels of naturally-secreted antibiotics that help protect corals from harmful bacteria;
  • Direct algal contact driven by overfishing and nutrient pollution destabilizes the coral microbiome, in some cases leading to a 6- to 9-time increase in mortality.

The findings, researchers say, make it clear that in the face of global warming, some of the best opportunities to protect coral reefs lie in careful management of fishing and protection of water quality. This would give corals their best chance to have a healthy microbiome and resist warmer conditions without dying.

Collaborators on this research were from Florida International University, the University of California/Santa Barbara, Penn State University, Rice University, the University of Florida/Gainsville, SymbioSeas and Marine Applied Research Center, and the Laboratoire d’Excellence.

-30-

Editor Notes: Video and audio are available to illustrate this story.

 

Interview with Rebecca Vega-Thurber:  http://bit.ly/1TSUe1N

Link to audio-only version of same interview: http://bit.ly/24ubTg0

YouTube view-only link of same video: https://youtu.be/dq8jtyuYp_U

Story By: 
Source: 

Rebecca Vega-Thurber, 541-737-1851

rebecca.vega-thurber@oregonstate.edu

Multimedia Downloads
Multimedia: 

Coral surveys

Divers in field study


Sampling coral microbiome


Testing coral microbiome


Experimental design


Study design


Parrot fish on coral reefs
Parrot fish cleaning coral

PNAS Study: Eddies enhance survival of coral reef fish in sub-tropical waters

NEWPORT, Ore. – Swirling eddies in the ocean have long been thought to be beneficial to organisms such as larval fishes residing within them because of enhanced phytoplankton production. However, direct evidence for this hypothesis has been hard to come by.

A new study published this week in Proceedings of the National Academy of Sciences (PNAS), which sequentially sampled tropical fish from their larval stages to their settlement in reefs, confirms the critical role of these oceanographic features.

Researchers found that young fish reared in nutrient-rich eddies in the Straits of Florida grew faster and had a survival advantage compared to their counterparts outside eddies, and were more likely to populate nearby reefs because of their more robust upbringing.

“Eddies upwell nutrients and provide a high-productivity environment that gives larval fishes growing there a head start on survival,” said Su Sponaugle, a marine biologist and principal investigator on the study who is affiliated with both Oregon State University and the University of Miami. “In cooler springtime waters, when larval fish are growing more slowly, the difference between fish raised inside or outside of eddies is small.

“But by August, when warm waters elevate fish growth rates, food becomes scarce and larval fishes residing inside eddies are more likely to survive.”

The study is important because it provides resource managers and fish population modelers with valuable new data, said Robert Cowen, director of Oregon State University’s Hatfield Marine Science Center, and a co-author on the PNAS paper.

“If there are areas where eddies predictably occur, these could be considered pelagic nursery areas that would warrant higher levels of protection from human interference,” Cowen said. “Further, the role of theses eddies should be incorporated into modeling efforts, which inform decision-makers. The influence of eddies may become even more important with warming oceans.”

In their study, the researchers collected larval fishes both inside and outside of eddies, focusing on three species – bluehead wrasse (Thalassoma bifasciatum), bluelip parrotfish (Cryptotomus roseus) and bicolor damselfish (Stegastes partitus). They determined the daily growth rates of the fish through examination of their otoliths, or ear stones, and found that those raised within the eddies had substantially higher growth rates than fish captured outside the eddies.

A few weeks later, they sampled young juveniles that had settled to nearby reefs and again using otoliths to chart daily growth rates of the fish were able to determine that almost all of those that survived to the juvenile stage had growth patterns similar to larvae from eddies.

Fish raised inside of eddies have different growth signatures in their otoliths than those raised outside eddies, explained Kathryn Shulzitski, lead author and assistant scientist at the University of Miami. “This is the first time we have been able to sample fish throughout their larval upbringing offshore to their life as juveniles on the reef and see which fish had a survival advantage.

“It was overwhelmingly slanted toward eddy-raised fish.”

The researchers theorize that larval fish residing outside of eddies either starve to death or become sufficiently weak that they are more susceptible to predators.

“Although we were focusing on three species of smaller reef fish, it is likely that the importance of eddies for larger species – including those sought by people for food – are the same,” Cowen said. “Likewise, this probably is not unique to the Florida Straits. Eddies are ubiquitous in waters around the globe and their role in mixing and stirring up nutrients is critical.”

Other authors on the PNAS study include Martha Hauff and Kristen Walter of the University of Miami. Hauff also is affiliated with Stonehill College in Massachusetts.

Story By: 
Source: 

Su Sponaugle, 541-867-0314, su.sponaugle@oregonstate.edu;

Bob Cowen, 541-867-0211, robert.cowen@oregonstate.edu

Multimedia Downloads
Multimedia: 

Bluehead wrasse (Photo by Evan D’Alessandro)
bluehead wrasse

Hydrothermal vents, methane seeps play enormous role in marine life, global climate

CORVALLIS, Ore. – The hydrothermal vents and methane seeps on the ocean floor that were once thought to be geologic and biological oddities are now emerging as a major force in ocean ecosystems, marine life and global climate.

However, even as researchers learn more about their role in sustaining a healthy Earth, these habitats are being threatened by a wide range of human activities, including deep-sea mining, bottom trawling and energy harvesting, scientists say in a report published in Frontiers in Marine Science.

Researchers from Oregon State University first discovered these strange, isolated worlds on the ocean bottom 40 years ago. These habitats surprised the scientific world with reports of hot oozing gases, sulfide chimneys, bizarre tube worms and giant crabs and mussels – life forms that were later found to eat methane and toxic sulfide.

“It was immediately apparent that these hydrothermal vents were incredibly cool,” said Andrew Thurber, an assistant professor in the OSU College of Earth, Ocean and Atmospheric Sciences, and co-author on the new report.

“Since then we’ve learned that these vents and seeps are much more than just some weird fauna, unique biology and strange little ecosystems. Rather than being an anomaly, they are prevalent around the world, both in the deep ocean and shallower areas. They provide an estimated 13 percent of the energy entering the deep sea, make a wide range of marine life possible, and are major players in global climate.”

As fountains of marine life, the vents pour out gases and minerals, including sulfide, methane, hydrogen and iron – one of the limiting nutrients in the growth of plankton in large areas of the ocean. In an even more important role, the life forms in these vents and seeps consume 90 percent of the released methane and keep it from entering the atmosphere, where as a greenhouse gas it’s 25 times more potent than carbon dioxide.

“We had no idea at first how important this ecological process was to global climate,” Thurber said. “Through methane consumption, these life forms are literally saving the planet. There is more methane on the ocean floor than there are other forms of fossil fuels left in the oceans, and if it were all released it would be a doomsday climatic event.”

In reviewing the status of these marine geological structures and the life that lives around them, a group of researchers from 14 international universities and organizations have outlined what’s been learned in the past four decades and what forces threaten these ecosystems today. The synthesis was supported by the J.M. Kaplan fund.

These vents and seeps, and the marine life that lives there, create rocks and habitat, which in some settings can last tens of thousands of years. They release heat and energy, and form biological hot spots of diversity. They host extensive mussel and clam beds, mounds of shrimp and crab, create some prime fishing habitat and literally fertilize the ocean as zooplankton biomass and abundance increases. While the fluid flows from only a small section of the seafloor, the impact on the ocean is global.

Some of the microorganisms found at these sites are being explored for their potential to help degrade oil spills, or act as a biocatalytic agent for industrial scrubbing of carbon dioxide.

These systems, however, have already been damaged by human exploitation, and others are being targeted, the scientists said. Efforts are beginning to mine them for copper, zinc, lead, gold and silver. Bottom trawling is a special concern, causing physical disturbance that could interfere with seeps, affect habitat and damage other biologic linkages.

Oil, gas or hydrate exploitation may damage seeps. Whaling and logging may interfere with organic matter falling to the ocean floor, which serves as habitat or stepping stones for species reliant on chemosynthetic energy sources. Waste disposal of munitions, sewage and debris may affect seeps.

The range of ecosystem services these vents and seeps provide is just barely beginning to be understood, researchers said in their report. As many of these habitats fall outside of territorial waters, vent and seep conservation will require international collaboration and cooperation if they are going to continue to provide ecosystem benefits.

Contributors to this report included researchers from the Scripps Institution of Oceanography, Florida State University, the National Institute of Water and Atmospheric Research in New Zealand, University of the Azores, Temple University, Universidade de Aveiro, the U.S. Geological Survey, University of the West Indies, Dalhousie University, University of Victoria, Duke University, Ghent University and the University of Hawaii at Manoa.

-30-

Editor’s note: Downloadable high resolution video; online “view only” video; live streamed video; and still photos are all available to illustrate this story. Please credit "Courtesy of D. Kelley, University of Washington, NSF/Ocean Observatories Initiative/Canadian Scientific Submersible Facility."

  • Video: Downloadable hydrothermal vents b-roll (Length 1:50)

https://drive.google.com/folderview?id=0B_nEpHVYyPtpM2F4bWxiY1dXeEU&usp=sharing

  • Video: Online view only hydrothermal vents b-roll (Length 1:50)

http://www.interactiveoceans.washington.edu/file/Inferno_Vent_at_Axial

  • Video: Live HD imagery streamed to shore 8 times/day. Every 3 hours, day and night, on this site you can watch live streaming video from about a mile below the oceans' surface, on the top of a submarine volcano known as Axial Seamount. Axial is located nearly 400 kilometers (~250 miles) due west of Astoria, Oregon on a mid-ocean ridge spreading center called the Juan de Fuca Ridge.  http://novae.ocean.washington.edu/story/Ashes_CAMHD_Live 
Story By: 
Source: 

Andrew Thurber, 541-737-4500

athurber@coas.oregonstate.edu

Multimedia Downloads
Multimedia: 

Tube worms
Tube worms