OREGON STATE UNIVERSITY

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Study finds prey density more important to predators than biomass

Note: The journal article this release is based on can be found at: http://dx.plos.org/10.1371/journal.pone.0053348

CORVALLIS, Ore. – Marine resource managers often gauge the health of species based on overall biomass, but a new study of predator-prey relationships in the Bering Sea found that it isn’t the total number of individuals that predators care about – it’s how densely they are aggregated.

It’s more than searching for an easy meal, the researchers say. Predators need to balance how much energy they expend in searching for food with the caloric and nutrient value of that which they consume. When prey doesn’t aggregate, however, the search for food becomes much more difficult – affecting the health of the predators’ offspring and the vitality of their overall population.

Results of the study were published this week in the journal PLOS ONE. The study was part of the Bering Sea Integrated Ecosystem Research Project, which was funded by the North Pacific Research Board and the National Science Foundation.

“We had to think very differently about these interactions, trying to see the world from the predators’ point of view,” said Kelly Benoit-Bird, an Oregon State University marine ecologist and lead author on the study. “When we first tried to identify good foraging locations for predator species we looked at areas of high prey numbers because it makes sense that they’d be where the food is. But the results didn’t match what we might have expected.

“Predator populations that should have been doing well, based on prey numbers or biomass, were in fact not doing well,” added Benoit-Bird, an associate professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences. “What we discovered is that smaller aggregations of prey are more attractive to predators if they are sufficiently dense.”

The findings are particularly important, scientists say, because almost all fisheries management is based on biomass – tons of fish – and not how those fish may be distributed in the sea.

In their study, the researchers looked at the feeding behaviors of three co-occurring species in the Bering Sea, all of which consume juvenile pollock or krill – black-legged kittiwakes, thick-billed murres and northern fur seals. When they attempted to find a spatial relationship between these predators and the pollock using areal biomass and numerical abundance, they found little correlation.

However, when they began finding small patches of prey at certain depths and of sufficient density, the predators were there. And though the scientists know why – feeding efficiency – they aren’t sure how.

“To be honest, we aren’t really sure how these predators – which may travel many miles – locate the densest aggregations at depths well below the surface – and often at night,” said Scott Heppell, a fisheries ecologist at Oregon State University and co-author on the PLOS ONE paper. “You wouldn’t think murres and fur seals would have that much in common, but in this case they do.”

“In a way, they’re looking for the same thing that commercial fishing fleets look for – high-quality prey in aggregations dense enough to be economical,” added Heppell, an assistant professor of fisheries and wildlife at OSU.

Benoit-Bird likened the predator-prey link to locating a box of popcorn in a darkened movie theater. You may have to search for it, she noted, but if you find the popcorn box, the payoff will be much more significant than what you might get by stumbling upon individual kernels in the dark that are spread throughout the theater – even though the number of kernels is the same.

That payoff is particularly meaningful for nurturing young, the researchers point out. During their two-year study, the research group tagged and observed female fur seals from St. Paul Island and Bogoslof Island as they swam hundreds of kilometers over a period of 1-2 weeks to gorge on nutrient-rich pollock then return to their homes to nurse pups.

They also tagged and observed adult murres and kittiwakes at St. Paul, St. George and Bogoslof Islands. The birds would capture local prey to feed their chicks during the day, but make numerous long flights at night to gorge on energy-rich, deep-water prey before returning to their nests to feed their chicks.

“It is a trade-off strategy,” said Benoit-Bird, a 2010 recipient of a MacArthur Fellowship. “They feed themselves in one place and nourish their offspring from another.”

This concept of prey “patchiness” can change rapidly, the researchers noted. Pollock aggregated only when the number of individuals in an area reached a certain threshold; below that threshold, they swam as individuals.

“If the population is sufficiently diffuse, the pollock don’t aggregate and that could spell trouble for species that prey upon them,” Heppell said. “A 10 percent shift in the number of fish could change how the entire stock behaves – and have a major impact on the birds, seals and other predators.”

Other authors on the PLOS ONE paper include Brian Battaile, Chad Nordstrom and Andrew Trites of the University of British Columbia; Brian Hoover and Nathan Jones, University of California’s Moss Landing Marine Laboratories; David Irons and Kathy Kuletz of the U.S. Fish and Wildlife Service in Anchorage; and Rosana Paredes, Robert Suryan and Chad Waluk of Oregon State University.

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Kelly Benoit-Bird, 541-737-2063

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2012 weather: Bookend wet spells sandwich summer drought

CORVALLIS, Ore. – 2012 will likely go down as the warmest year on record for the lower 48 states, but it may be remembered just as much for its extreme events – and Oregon was no exception.

Though the state didn’t experience anything like super-storm Sandy or major blizzards that paralyzed communities, it did experience a pronounced summer drought, sandwiched by “atmospheric river events” that drenched Oregonians in January and late November.

Kathie Dello, deputy director of the Oregon Climate Service at Oregon State University, said the impacts from the three phenomena were significant.

“The state was really dry during the July to September period and it really extended into October,” Dello said. “In fact, it was the second driest summer period on record, which made it a big year for wildfires. Oregon (1.26 million acres) was second in the nation to Idaho (1.54 million acres) for most acres burned and many private woodland owners had to close their lands to hunters until mid-October because of fire danger. That doesn’t happen often.”

“The two wet weather events affected western Oregon to a great extent, and caused some fairly serious flooding,” added Dello, who is in OSU’s College of Earth, Ocean, and Atmospheric Sciences. “There were also some rather damaging windstorms.”

One series of storms in January caused major flooding in the Willamette Valley and another series in late November soaked the southwestern portion of the state. These bookend wet spells made the year wetter than normal in western Oregon, though eastern Oregon ended up drier than average. Statewide records go back 118 years.

With a couple of days left in the year, Corvallis is likely to close 2012 with the fourth wettest year on record, with 58.72 inches of precipitation through Dec. 27. The average over the past 30 years has been 42.71 inches. Totals of other Oregon cities, with data gathered in part from the National Weather Service in Portland, include:

  • Medford has received 26.67 inches through Dec. 27, well above its average of 18.35 inches. On November 29, the town received its first rainfall of more than two inches since 2005.
  • Portland has logged 50.43 inches in 2012, fourth highest on record, and well above its average of 36.1 inches.
  • Salem is in the midst of the seventh wettest year on record with 54.38 inches; its average over the past 30 years is 39.67 inches.
  • Astoria has received 91.01 inches, eighth most on record, and more than 23 inches above its average of 67.53 inches.

“Almost all of the wet weather records are from 1996, when the state experienced some rather spectacular flooding,” Dello said. “That was a ‘100-year flood event’ and the records back it up.”

Corvallis had 73.21 inches in 1996; Portland was at 63.20, Salem at 66.96, and Medford at 31.41. Astoria was one of the few places that didn’t peak that year. Its record year was 1950, when it got 113.34 inches.

The chaotic weather in 2012 was fitting in a way – this coming winter is the first time since 2003 that the western United States wasn’t affected by either El Niño or a La Niña conditions. El Niños typically result in warmer and drier winter weather; La Niñas are usually wetter, as it was in January, which was on the tail end of last winter’s La Niña.

“We are neither, for the first time in almost a decade,” Dello said. “Officially we are ENSO-neutral, or what some people call ‘La Nada.’”

Weather-lovers can learn more about Oregon weather by following Dello on Twitter at: www.twitter.com/orclimatesvc. The state is also looking for volunteers to collect precipitation data. For more information, go to http://www.cocorahs.org/.

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Kathie Dello, 541-737-8927

Study: High stream temperatures, low flow creating extreme conditions

CORVALLIS, Ore. – A newly published study by researchers at Oregon State University and two federal agencies concludes that high temperatures coupled with lower flows in many Northwest streams is creating increasingly extreme conditions that could negatively affect fish and other organisms.

The study, published in the professional journal Hydrobiologia, was funded and coordinated by the U.S. Geological Survey and the research branch of the U.S. Forest Service. It points to climate change as the primary reason for the extreme conditions.

“The highest temperatures for streams generally occur in August, while lowest flows take place in the early fall,” said Ivan Arismendi, a research professor in OSU’s Department of Fisheries and Wildlife. “Each period is important because it is a time of potentially high stress on the organisms that live in the stream. If they occur closer in time – or together – they could create double trouble that may be greater than their combined singular effects.”

Arismendi, who was lead author on the paper, said climate change appears to play a role as snowpack levels lessen and snow begins melting earlier in the spring. Peak stream flows are coming earlier in the year, stretching out the amount of time when river flows are low.

“What results is that low flows are moving closer and closer to the time of the year when stream temperatures are highest,” Arismendi said, “and that is not good.”

The study looked at 22 “minimally human-influenced” streams from the period of 1950 to 2010, located in Washington, Oregon, California, Nevada, Montana and Idaho. The researchers found the hydrology of the streams was complex and differed among streams; while weather extremes affected all of the streams, the impact seems to be mediated by the influence of groundwater.

“Other studies have shown that high temperatures in streams lead to less oxygen and more thermal stress,” said co-author Jason Dunham, an aquatic ecologist with the U.S. Geological Survey. “Low flows reduce the amount of suitable habitat and may lead to high density and overcrowding, more predation, changes in predator-prey relationships, and more competition – at least, among salmonids.”

This study focused on the physical processes on the streams, Arismendi emphasized, and needs to be followed by biological studies.

“Coupling of low flow with high temperatures can have significant hydrologic implications in maintaining stream water quality,” said Mohammad Safeeq, an OSU post-doctoral researcher in the College of Earth, Ocean, and Atmospheric Sciences and a co-author on the paper.

Arismendi said that over the years, weather and stream flow can be influenced by climate drivers like El Nino, La Nina, the Pacific Decadal Oscillation and other phenomena. But over the 60-year time frame covered by the study, the climate warmed appreciably, leading to lower flows and earlier peak flows.

“These streams have high natural variability,” Arismendi said, “but the general pattern holds true.”

Interestingly, Arismendi said that stream temperatures are not always higher on an annual scale despite a regional trend that has shown warming air temperatures. This could be because of increased snowmelt, he pointed out, or complex hydrological cycles.

“Even though our studies are showing that stream processes are much more complex than initially thought we are able to identify trends toward increasing synchrony in timing of low flows and high temperatures,” Arismendi said.

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Ivan Arismendi, 541-750-7443

OSU to co-host meeting in Tillamook on ocean acidification, low oxygen

TILLAMOOK, Ore. – A public forum on Tuesday, Oct. 23, in Tillamook will explore the current and potential future impacts of two emerging phenomena along the Oregon coast – increasing ocean acidity and seasonal incidence of low-oxygen waters, or “hypoxia.”

A series of speakers will present the latest research at the free community event, “Demystifying Coastal Hypoxia & Ocean Acidification,” which begins at 6:30 p.m. at Tillamook Bay Community College Room 214/215. A panel discussion will follow, focusing on what individuals, communities, government agencies and others can do to reduce and manage potential impacts of ocean acidification and hypoxia, both globally and locally.

The event is particularly timely, organizers say, as the fishing industry, agencies and scientists are expressing increasing alarm at the trend of more acidic ocean waters that have less oxygen to support marine life. The effects already are being felt in Oregon, where acidic, low-oxygen seawater contributed to the death of a substantial fraction of the young oysters produced by the Whiskey Creek Shellfish Hatchery near Tillamook.

Oregon is a prime location at which to study these threats, scientists say, and the public will have an opportunity to learn more about them at the forum.

Hosted by the Partnership for Interdisciplinary Studies of Coastal Oceans program led by Oregon State University, the forum will feature researchers from OSU, Oregon Department of Fish and Wildlife, Whiskey Creek Shellfish Hatchery, and the National Oceanic and Atmospheric Administration. It is supported by Oregon Sea Grant.

More information on the event is available at: http://www.piscoweb.org/node/522

Speakers and panelists include Francis Chan and Jack Barth of OSU, who have documented and explained increasing hypoxia events off Oregon; Burke Hales and George Waldbusser of OSU, who have helped Whiskey Creek Shellfish Hatchery offset the effects of acidic and hypoxic water that had been killing juvenile oysters; Alan Barton, manager of the Whiskey Creek hatchery; Steve Rumrill, the head of ODFW’s shellfish program, Waldo Wakefield of NOAA, who studies how environmental factors like hypoxia influence fish abundance and distribution; and others.

Tillamook Bay Community College is located at 4301 3rd St. in Tillamook.

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Joe Tyburczy, 541-231-9780

Fifty years later: Legacy of Columbus Day storm still stands

CORVALLIS, Ore. – Nearly half a century after it ripped through the Pacific Northwest, people still talk about the Columbus Day storm of 1962 – and with good reason.

With wind gusts measured at 145 miles per hour – and peak velocity that may have reached as high as 175 mph, the storm demolished trees, homes and lives. As many as 46 deaths were attributed to the storm, and hundreds of Oregonians were injured, making it the second deadliest weather event in the state’s history.

Some people have called it the perfect storm, but in truth, it was three separate storms, says Kathie Dello, deputy director of the Oregon Climate Service at Oregon State University.

“The Columbus Day storm has frequently been labeled as a typhoon, but that is somewhat erroneous,” Dello said. “It was the remnant of a typhoon that became extratropical and hit the West Coast in three waves, but they get lumped together in people’s minds as one event.”

Dello said three key things happened to create the monstrous weather event that became known as the Columbus Day storm. Remnants of Typhoon Freda, which formed in early October, regained intensity after it moved into an area where cool air from the Gulf of Alaska met warm, moist tropical air. The newly energized system moved up the coast and a low pressure system developed intensively. Finally, the combination of the west-to-east pressure gradient with the northward path of the storm funneled the system between the Coast Range and the Cascades – right up the Willamette Valley.

“If the winds had come from the west, the pressure gradient would have changed and the damage would not have been nearly as severe,” said Dello, who is in OSU’s College of Earth, Ocean, and Atmospheric Sciences. “We have extratropical storms visit us frequently. But the intensity of the low pressure, combined with the direction of the storm, and our topography made this one historic.”

What also made the Columbus Day storm unusual, Dello said, was that it took place in October – well before the winter storm season.

“It is the only major windstorm on record in the Pacific Northwest for October,” she said.

During the storm, the pressure level dropped to at least 960 millibars, Dello said, which is equivalent to a Category 3 hurricane. The contrast with the high pressure system to the north intensified the storm, which swept up the Willamette Valley leaving a swath of destruction.

The manually operated wind gauge in Corvallis recorded a gust of 127 mph, before the operator fled, leaving a note behind that merely stated, “abandoned station.” Sustained winds, of a minute or longer in duration, reached as high as 69 mph.

Cape Blanco, regarded as perhaps the windiest spot along the coast, recorded the highest official gust – 145 mph. But the entire western portion of the state was battered, Dello said, by amazingly strong gusts and sustained periods of high winds. Portland recorded a gust of 116 mph near the Morrison Street Bridge. Mount Hebo Air Force Station recorded a gust of 130 mph.

The storm reached into Washington, as well, before dissipating, battering Olympia (78 mph); McChord Air Force Base (88 mph); Renton, (100 mph); and Bellingham (98 mph).

As the storm began, it dumped heavy rain on California, forcing the postponement of a World Series game between the San Francisco Giants and the New York Yankees. As it moved into Oregon, the rain lessened but the winds intensified with the pressure change.

Some reports say the storm damaged as many trees in Oregon and Washington as the combined annual timber harvest of both states. Power was not only knocked out throughout western Oregon, but entire distribution systems were destroyed and some communities went weeks without electricity. The economic impact just in Oregon was an estimated $200 million at the time, which is equal to somewhere in the vicinity of $1.4 billion in today’s dollars, according to OSU political scientist Robert Sahr, who studies inflation conversion.

Many homes were destroyed and it was considered the worst natural disaster in the country in 1962. The only weather-related event in Oregon history that was worse, Dello said, was the Heppner Flood in 1903, which resulted in 247 fatalities.

“The Heppner Flood was different in that it was a flash flood from intense thunderstorms that in a period of minutes overwhelmed Willow Creek and its tributaries,” Dello said. “It is one of the state’s few weather disasters east of the Cascades.”

Fifty years after the Columbus Day storm, weather analysts still debate whether this is a once a century event, or something even more unusual. Dello says she often is asked if such a storm could happen again.

“It took a combination of events to create the Columbus Day storm,” Dello said, “and the cumulative effect of those events was enormous. But none of the individual factors was all that unusual, so yes, it could very well happen again. And if it does, the damage could be even more devastating because there are so many more people and houses than in 1962.

“In Oregon, we are perhaps more vulnerable to the damage because epic storms happen so rarely,” Dello pointed out. “It’s hard to prepare for a once-in-a century storm.”

Dello frequently provides weather facts and historical data via Twitter at: www.twitter.com/orclimatesvc.

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Kathie Dello, 541-737-8927

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MU quad at OSU

 

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Bridge in Corvallis

OSU scientists part of intensive planning for tricky Mars landing

CORVALLIS, Ore. – If all goes according to plan, the Mars Science Laboratory, or MSL, will approach the Red Planet late on Sunday, Aug. 5, before slowing, deploying its parachutes, and lowering the rover “Curiosity” via cable to explore the surface.

Designing an autonomously controlled spacecraft to go from an initial speed of 13,000 miles per hour to almost zero in just seven minutes – on a planet where winds howl and temperatures are frigid – requires off-the-charts engineering acumen, as well as in-depth knowledge of Mars’ atmospheric conditions.

Researchers at Oregon State University have been working for the past four years with the Jet Propulsion Laboratory in Pasadena, Calif., on a computer model of the Martian atmosphere that the project engineers have used to make adjustments in the spacecraft’s control system for the landing.

“They call it ‘the seven minutes of terror’ because so much will happen in such a small window of time – and it is when the greatest risks to the mission take place,” said Jeff Barnes, a professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences. “MSL is one of the most robust space vehicles ever built but there will still be a lot of tension until those few minutes are over and we know that the landing was a good one.”

The OSU Mars atmospheric model is one of two that NASA/JPL engineers have been using to make small adjustments to the on-board software that will guide the entry, descent and landing of the Mars Science Laboratory. Based on orbital observations of atmospheric conditions gleaned from the Mars Reconnaissance Orbiter, the model calculates and predicts what conditions are likely to be. It can be adapted in different “nests” to simulate the Mars atmosphere over a very wide range of spatial scales.

And the higher the model resolution, Barnes says, the better.

“The critical atmospheric factors are wind, temperature and density,” Barnes noted. “Density is the most important because you are trying to slow the spacecraft down and enable it to land within 10 to 15 kilometers of the prime target for science.  Densities lower than expected could be real trouble, because the spacecraft will automatically ‘dive’ to lower altitudes to find higher densities in order to slow down sufficiently.  If it gets too low before the parachutes are deployed, a safe landing would be jeopardized.”

“Our Mars model has a spatial resolution that can get down to a horizontal scale of 4-5 kilometers, which provides the engineers with very good information about local atmospheric conditions,” Barnes said.

Created by Barnes and OSU research associate Dan Tyler, the Oregon State atmospheric model of Mars is a continuation of their previous research on the Red Planet. Both OSU scientists worked on the Phoenix Mission, which landed in the north polar region of Mars in 2008, and Barnes’ involvement in Mars research dates all of the way back to the historic Viking mission.  More recently, Barnes was heavily involved in the 1997 Mars Pathfinder mission, which operated the first rover on the Mars surface. 

But this is the most ambitious, and expensive (at about $2.5 billion), NASA Mars mission yet. The Mars Science Laboratory is designed to descend inside the very large Gale crater, hover at about 20 meters above the surface, and lower the Curiosity rover via cables to the surface. Past missions have “bounced” rovers down inside of giant airbag padding, but this rover, weighing one ton, is much bigger and heavier than those in the past.

“It’s about the size of a Mini-Cooper,” Barnes said, “so they’ve built a sophisticated “sky-crane” system to lower it to the surface, then explosively sever the cables, and fire rockets to move the spacecraft away from the area so it doesn’t fall onto and crush the rover. This is all totally new – it’s never been done before.”

The greatest risks, Barnes said, begin at about 15-20 kilometers above the surface.

“In this altitude region, the craft begins to fly almost horizontally over the Martian surface, which buys more time to slow itself down to a reasonable speed before the parachute deployment,” Barnes said. “That’s where the automatic control adjustments based on the expected temperatures – actually the speed of sound – and the winds and densities become the most critical.” 

The craft will land just south of the Martian equator – the first time a spacecraft has landed in the planet’s southern hemisphere. It is mid-winter in the south, approaching the spring equinox and conditions are relatively mild. Predictions for the week of the landing include minimum temperatures of minus-110 degrees Fahrenheit, maximum temperatures of a balmy minus-10 degrees, and winds of about 10 miles an hour very near to the surface – though atmospheric winds will be stronger at higher altitudes. The biggest atmospheric threat to the landing is dust storm activity.

“If there are orbiter observations of a dust storm forming that could cause large changes in the dustiness of the atmosphere near Gale Crater, then there will be discussions about making last minute modifications to the onboard programming,” Tyler said. “But I think that this is unlikely. There is a good deal of confidence now that the spacecraft system is very capable of dealing with the natural variability and will be able to land safely with great accuracy.” 

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Jeff Barnes, 541-737-5685

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Mars Science Laboratory

Mars Science Laboratory

13-year Cascadia study complete – and earthquake risk looms large

CORVALLIS, Ore. – A comprehensive analysis of the Cascadia Subduction Zone off the Pacific Northwest coast confirms that the region has had numerous earthquakes over the past 10,000 years, and suggests that the southern Oregon coast may be most vulnerable based on recurrence frequency.

Written by researchers at Oregon State University, and published online by the U.S. Geological Survey, the study concludes that there is a 40 percent chance of a major earthquake in the Coos Bay, Ore., region during the next 50 years. And that earthquake could approach the intensity of the Tohoku quake that devastated Japan in March of 2011.

“The southern margin of Cascadia has a much higher recurrence level for major earthquakes than the northern end and, frankly, it is overdue for a rupture,” said Chris Goldfinger, a professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences and lead author of the study. “That doesn’t mean that an earthquake couldn’t strike first along the northern half, from Newport, Ore., to Vancouver Island.

“But major earthquakes tend to strike more frequently along the southern end – every 240 years or so – and it has been longer than that since it last happened,” Goldfinger added. “The probability for an earthquake on the southern part of the fault is more than double that of the northern end.”

The publication of the peer-reviewed analysis may do more than raise awareness of earthquake hazards and risks, experts say. The actuarial table and history of earthquake strength and frequency may eventually lead to an update in the state’s building codes.

“We are considering the work of Goldfinger, et al, in the update of the National Seismic Hazard Maps, which are the basis for seismic design provisions in building codes and other earthquake risk-mitigation measures,” said Art Frankel, who has dual appointments with the U.S. Geological Survey and the University of Washington.

The Goldfinger-led study took four years to complete and is based on 13 years of research. At 184 pages, it is the most comprehensive overview ever written of the Cascadia Subduction Zone, a region off the Northwest coast where the Juan de Fuca tectonic plate is being subducted beneath the continent. Once thought to be a continuous fault line, Cascadia is now known to be at least partially segmented.

This segmentation is reflected in the region’s earthquake history, Goldfinger noted.

“Over the past 10,000 years, there have been 19 earthquakes that extended along most of the margin, stretching from southern Vancouver Island to the Oregon-California border,” Goldfinger noted. “These would typically be of a magnitude from about 8.7 to 9.2 – really huge earthquakes.

“We’ve also determined that there have been 22 additional earthquakes that involved just the southern end of the fault,” he added. “We are assuming that these are slightly smaller – more like 8.0 – but not necessarily. They were still very large earthquakes that if they happened today could have a devastating impact.”

The clock is ticking on when a major earthquake will next strike, said Jay Patton, an OSU doctoral student who is a co-author on the study.

“By the year 2060, if we have not had an earthquake, we will have exceeded 85 percent of all the known intervals of earthquake recurrence in 10,000 years,” Patton said. “The interval between earthquakes ranges from a few decades to thousands of years. But we already have exceeded about three-fourths of them.”

The last mega-earthquake to strike the Pacific Northwest occurred on Jan. 26, 1700. Researchers know this, Goldfinger said, because written records in Japan document how an ensuing tsunami destroyed that year’s rice crop stored in warehouses.

How scientists document the earthquake history of the Cascadia Subduction Zone is fascinating. When a major offshore earthquake occurs, Goldfinger says, the disturbance causes mud and sand to begin streaming down the continental margins and into the undersea canyons. Coarse sediments called turbidites run out onto the abyssal plain; these sediments stand out distinctly from the fine particulate matter that accumulates on a regular basis between major tectonic events.

By dating the fine particles through carbon-14 analysis and other methods, Goldfinger and colleagues can estimate with a great deal of accuracy when major earthquakes have occurred over the past 10,000 years.

Going back further than 10,000 years has been difficult because the sea level used to be lower and West Coast rivers emptied directly into offshore canyons. Because of that, it is difficult to distinguish between storm debris and earthquake turbidites.

“The turbidite data matches up almost perfectly with the tsunami record that goes back about 3,500 years,” Goldfinger said. “Tsunamis don’t always leave a signature, but those that do through coastal subsidence or marsh deposits coincide quite well with the earthquake history.”

With the likelihood of a major earthquake and possible tsunami looming, coastal leaders and residents face the unenviable task of how to prepare for such events. Patrick Corcoran, a hazards outreach specialist with OSU’s Sea Grant Extension program, says West Coast residents need to align their behavior with this kind of research.

“Now that we understand our vulnerability to mega-quakes and tsunamis, we need to develop a culture that is prepared at a level commensurate with the risk,” Corcoran said. “Unlike Japan, which has frequent earthquakes and thus is more culturally prepared for them, we in the Pacific Northwest have not had a mega-quake since European settlement. And since we have no culture of earthquakes, we have no culture of preparedness.

“The research, though, is compelling,” he added. “It clearly shows that our region has a long history of these events, and the single most important thing we can do is begin ‘expecting’ a mega-quake, then we can’t help but start preparing for it.”

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Chris Goldfinger, 541-737-5214

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Coos Bay bridge

Coos Bay bridge

Program to monitor harmful algal blooms to end next month

CORVALLIS, Ore. – A federally funded program that has provided Oregon with an early warning system for harmful algal blooms will end next month.

For the past five years, researchers at Oregon State University and the Oregon Department of Fish and Wildlife (with collaborators from the University of Oregon) have monitored phytoplankton blooms off the Oregon coast, and conducted toxin analyses of the different species. When toxin levels rose, they could alert the Oregon Department of Agriculture, which stepped up its sampling of clams and mussels to protect the public from domoic acid and paralytic shellfish poisoning.

Begun in 2007, the five-year grant from the National Oceanic and Atmospheric Administration runs out at the end of August. The Oregon Department of Agriculture will continue sampling clams, mussels and other shellfish for bioaccumulation of toxins, but the early warning system will be gone.

“The Oregon Department of Agriculture does an excellent job of analyzing shellfish for toxins, but the concern is there is no way to know that we have a problem until the toxins are already in the clams and mussels,” said Angelicque “Angel” White, an OSU oceanographer and principal investigator on the grant. “It is a shame to close beaches after Oregonians have already harvested and eaten their catch.”

On July 6, the Oregon Department of Agriculture closed much of the central Oregon coast to mussel harvests due to elevated levels of paralytic shellfish toxins. The closure was based on an alert from phytoplankton monitoring funded by the NOAA grant.

The NOAA grant was aimed at creating a model of predicting harmful algal blooms and developing a program to alert local authorities. “The NOAA mission is to fund such programs for a period of time, find something that works, and then turn it over to the state,” White said. None of the state agencies, however, have stepped up to support early monitoring efforts based on phytoplankton counts.

White, who is a faculty member in OSU’s College of Earth, Ocean, and Atmospheric Sciences, said the phytoplankton monitoring could continue with a trained person working half-time, with a modest amount of equipment. “It amounts to little more than a microscope, a bucket, time and a bit of experience so that you know what you’re looking for,” she said.

“For a state that values tourism and recreation – and the dollars they bring – this really seems like low-hanging fruit,” White added.

Marc Suddleson, a NOAA harmful algal bloom program manager, said his agency provides funding to pilot “innovative harmful algal bloom solutions such as the Oregon early warning program” because HAB problems are affecting every United States coastal region, and to aid state agencies that are financially constrained. But state funding is needed to sustain the monitoring improvements, Suddleson said.

“The Oregon team has repeatedly demonstrated that better monitoring can give state and local officials an early warning, but the challenging budget climate facing Oregon state agencies makes its future uncertain,” Suddleson said.

Phytoplankton blooms are a normal ocean process, critical to maintaining a productive marine food web off the Oregon coast. Spring and summer winds bring deep, nutrient-rich water to the surface - a process called “upwelling.” When that water is exposed to sunlight, it creates phytoplankton blooms, tiny plants that are a food source for zooplankton and other creatures, which in turn become prey for larger animals.

But certain species of phytoplankton have the ability to produce toxins that can be harmful to humans. One called Pseudo-nitzschia produces domoic acid, which bio-accumulates in the tissues of razor clams and mussels and can cause illness, and even death in humans. Another species, Alexandrium, produces saxitoxin, which can lead to paralytic shellfish poisoning if ingested.

“Pseudo-nitzschia is harder to predict and is involved in all kinds of biological witchcraft,” White said. “Some cells are toxic and some are not – even in the same patch of water. We don’t yet understand what turns them on or off. But we can tell when they become toxic at a dangerous level.

“Alexandrium, on the other hand, is a charismatic little dinoflagellate that likes warmer, calmer water,” she added. “They usually make up a small percentage of the total plankton population, but they’re reliably toxic. So if you scoop some ocean water into a bucket, and you actually see increases in their cell numbers, you can be pretty sure the chances for paralytic shellfish poisoning go up.

“That’s as cheap, easy and reliable an early warning system as you could ask for.”

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Angel White, 541-737-6397

New deglaciation data opens door for earlier First Americans migration

CORVALLIS, Ore. – A new study of  lake sediment cores from Sanak Island in the western Gulf of Alaska suggests that deglaciation there from the last Ice Age took place as much as1,500 to 2,000 years earlier than previously thought, opening the door for earlier coastal migration models for the Americas.

The Sanak Island Biocomplexity Project, funded by the National Science Foundation, also concluded that the maximum thickness of the ice sheet in the Sanak Island region during the last glacial maximum was 70 meters – or about half that previously projected – suggesting that deglaciation could have happened more rapidly than earlier models predicted.

Results of the study were just published in the professional journal, Quaternary Science Reviews.

The study, led by Nicole Misarti of Oregon State University, is important because it suggests that the possible coastal migration of people from Asia into North America and South America – popularly known as “First Americans” studies – could have begun as much as two millennia earlier than the generally accepted date of ice retreat in this area, which was 15,000 years before present.

Well-established archaeology sites at Monte Verde, Chile, and Huaca Prieta, Peru, date back 14,000 to 14,200 years ago, giving little time for expansion if humans had not come to the Americas until 15,000 years before present – as many models suggest.

The massive ice sheets that covered this part of the Earth during the last Ice Age would have prevented widespread migration into the Americas, most archaeologists believe.

“It is important to note that we did not find any archaeological evidence documenting earlier entrance into the continent,” said Misarti, a post-doctoral researcher in Oregon State’s College of Earth, Ocean, and Atmospheric Sciences. “But we did collect cores from widespread places on the island and determined the lake’s age of origin based on 22 radiocarbon dates that clearly document that the retreat of the Alaska Peninsula Glacier Complex was earlier than previously thought.”

“Glaciers would have retreated sufficiently so as to not hinder the movement of humans along the southern edge of the Bering land bridge as early as almost 17,000 years ago,” added Misarti, who recently accepted a faculty position at the University of Alaska at Fairbanks.

Interestingly, the study began as a way to examine the abundance of ancient salmon runs in the region. As the researchers began examining core samples from Sanak Island lakes looking for evidence of salmon remains, however, they began getting radiocarbon dates much earlier than they had expected. These dates were based on the organic material in the sediments, which was from terrestrial plant macrofossils indicating the region was ice-free earlier than believed.

The researchers were surprised to find the lakes ranged in age from 16,500 to 17,000 years ago.

A third factor influencing the find came from pollen, Misarti said.

“We found a full contingent of pollen that indicated dry tundra vegetation by 16,300 years ago,” she said. “That would have been a viable landscape for people to survive on, or move through. It wasn’t just bare ice and rock.”

The Sanak Island site is remote, about 700 miles from Anchorage, Alaska, and about 40 miles from the coast of the western Alaska Peninsula, where the ice sheets may have been thicker and longer lasting, Misarti pointed out. “The region wasn’t one big glacial complex,” she said. “The ice was thinner and the glaciers retreated earlier.”

Other studies have shown that warmer sea surface temperatures may have preceded the early retreat of the Alaska Peninsula Glacier Complex (APGC), which may have supported productive coastal ecosystems.

Wrote the researchers in their article: “While not proving that first Americans migrated along this corridor, these latest data from Sanak Island show that human migration across this portion of the coastal landscape was unimpeded by the APGC after 17 (thousand years before present), with a viable terrestrial landscape in place by 16.3 (thousand years before present), well before the earliest accepted sites in the Americas were inhabited.”

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Nicole Misarti, 541-737-2065

OSU scientist awarded prestigious Guggenheim Fellowship

CORVALLIS, Ore. – Peter Clark, an Oregon State University scientist who is known internationally for his work on climate history, has received a prestigious fellowship from the John Simon Guggenheim Memorial Foundation.

Clark is the lone recipient nationally in the category of Earth Sciences. Most of the Guggenheim fellows are in humanities and social science fields.

Clark is a professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences, where his research has focused on the relationship between ice sheets and global climate, and the impact of a changing climate on sea level. He is a coordinating lead author on the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report, which is due out in 2013.

An OSU faculty member since 1988, Clark is author of more than 120 peer-reviewed science articles, many of which have been published in Science and Nature. His latest publications have focused on the underlying mechanisms that drove the Earth out of its latest Ice Age.

The 2012 Guggenheim Fellowships were awarded to 181 scholars, artists and scientists, chosen from among 3,000 applicants. Selection is based on prior achievement and exceptional promise, according to the Guggenheim Foundation.

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Peter Clark, 541-737-1247