OREGON STATE UNIVERSITY

marine science and the coast

Researchers find hydrothermal vent fields in far north

BERGEN (Norway) - Scientists from the University of Bergen and Oregon State University have discovered the northernmost hydrothermal vents in the world along the Mohns Ridge in the Arctic Ocean.

"I've seen a lot of hydrothermal systems all over the world's oceans," said Adam Schultz, a geophysicist from OSU's College of Oceanic and Atmospheric Sciences, "and these Arctic fields are spectacular."

The three-week expedition was led by marine geologist Rolf Pedersen of the University of Bergen, who has been exploring the Arctic Ridge system from Iceland to Spitzbergen Island since 1999. The scientists, who were aboard the G.O. Sars research vessel, used a remotely operated vehicle to explore the vent fields, which they discovered around latitude 71 degrees, north of Iceland.

Much of the Arctic Ridge system is unexplored, and a vent field on the shelf of Iceland is the only one that scientists have seen in the northern latitudes. Unlike that Icelandic field, however, the newly discovered vent fields are full of life, according to Pedersen.

"There were huge numbers of chimneys - 30, 40, 50 or more," Pedersen said. Shrimp, anemones and bacterial mats dominated the animal life at the site. The researchers also found a type of tubeworm on the vent structures and in the outlying area - an important discovery, they say, because tubeworms had previously only been observed in Pacific Ocean vent fields.

Schultz used a temperature and flow sensor, called an isosampler, to help document the characteristics of the new vent fields.

"We found two large high-temperature fields and as we explored them, we would come upon a large mound of chimneys with superheated water jetting out of them," Schultz said. "Then in the distance, we'd see another mound and then beyond that, another one, and so on."

Temperatures in one field reached as high as 260 degrees C, and the scientists believe they may have approached 300 degrees C in the second field, although they were unable to measure them.

The OSU scientist said there also is a vast low-temperature field in the region that supports a diverse community of life, including large sea-lilies that "sit atop mineral/bacterial chimney-like structures that look at the world like pineapples."

"That is a particularly strange form of vent," Schultz said, "because the fluids coming out of these vents come out at temperatures only a fraction of a degree above the temperature of the background seawater and that is very cold - below zero Celsius - which is only possible in the Arctic.

"I'm not sure if we can even call these 'hydrothermal' vents," he added. "Perhaps they are 'hydrocryo' vents, meaning vents that emit cold water."

Schultz's team carried out measurements of the water flowing out of the vents at both the high-temperature and low-temperature fields. His team included Phil Taylor, an oceanic engineer who has a dual faculty appointment with OSU and Cardiff University in the United Kingdom.

They used the isosampler to determine that the fluids flowing from the vents had undergone "phase separation," which means they had been superheated sufficiently to have boiled - even at the enormous pressures of the deep seafloor. This process produces pure water vapor, Schultz says, as well as heated seawater and a heated briny fluid.

"This is typical of seawater that has encountered hot magma at depth beneath the seafloor, then vents out through smoker chimneys," Schultz pointed out. The vent fields were discovered at depths of 500 to 700 meters.

Pedersen said the researchers ironically had come close to discovering the vents on a previous voyage, when they were within about 500 meters from the spot the fields were located. Gales and rough seas complicated those previous efforts, he added.

This time, the researchers were able to locate the fields, which are about 100 to 200 meters in size. Yet they still had logistical problems.

"The chimneys were so dense that it was difficult in some areas to get the ROV (remotely operated vehicle) in there," Pedersen said. "In fact, we got the ROV cable stuck on one of them. It almost melted."

The researchers plan to return next year to more precisely identify the animals discovered at the vents, sample the microbes, and perform more detailed studies of the water column above the fields.

The scientists also believe there are additional vents fields to discover.

The study was part of the BioDeep project supported by the Norwegian Research Council. The project, which includes researchers in Norway, the United States and Sweden, investigates microbial life in the ocean's floor. OSU and the University of Bergen are collaborating on these deep biosphere studies. In addition to Schultz and Taylor, OSU oceanographer Martin Fisk is a key scientist in that collaboration.

More information on the cruise is available online at: www.interridge.org/sciencewriteratsea/Norway2005/index.html

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Adam Schultz, 541-737-9832

Another "Dead Zone" may loom off Oregon Coast

CORVALLIS - The Pacific Ocean off of Oregon has experienced a die-off of birds, declining fisheries and wildly fluctuating conditions in the past few months, and has set the stage for another hypoxic "dead zone" like those of 2002 and 2004, according to experts at Oregon State University.

This is the third year in the past four that has demonstrated significantly unusual ocean events, the researchers say, a period unlike any on record. The events have not all been the same. This year's ocean behavior is particularly bizarre, and there is no proof what is causing it.

But extreme variability such as this, OSU researchers say, is consistent with what scientists believe will occur as a result of global warming.

"All the climate models predict increased variability associated with global climate change," said Jane Lubchenco, the Wayne and Gladys Valley Professor of Marine Biology at OSU. "And there is no doubt that what is going on right now off Oregon is not normal."

In May and June when seasonal "upwelling" events should have begun that bring cold, nutrient rich water to the surface, the ocean was 8-11 degrees warmer than usual and had chlorophyll levels, a measure of productivity, about one-fifth to one-sixth of normal, said Lubchenco. As a result, scientists were observing dead birds on beaches, major declines in fisheries, and other symptoms of a marine food web that was literally starving.

Then in mid-July, it appears that a normal, strong upwelling event finally began, bringing cool water and lots of nutrients. The resulting intense bloom of microscopic plants coupled with low oxygen levels near the ocean floor set the stage for another "dead zone" event this year.

"The nearshore ocean right now looks like a brown pea soup," said Lubchenco, a director of the Partnership for Interdisciplinary Studies of Coastal Oceans, a pioneering research cooperative on the West Coast. "Just in the past couple weeks there was a spectacular bloom of diatoms."

Some upwelling is essential and desirable. But too much can lead to a glut of phytoplankton which in turn decay and, in combination with the right types of winds and currents, lead to over-consumption of the remaining oxygen in the water and a die-off of marine life.

The oceans and life they support are in a delicate physical and biological balance to sustain the marine ecosystem, Lubchenco said. Unusually wide variations in natural systems can lead to critical problems - as they have repeatedly in recent years. The intense "dead zone" events that occurred in 2002 and 2004 killed a wide range of fish, crabs and other marine species, literally suffocating them. Dissolved oxygen levels at the time were historically low.

Ronald Neilson, a professor of botany with OSU and ecologist with the U.S.D.A. Forest Service, is an expert on the ecological impacts of global climate change. What is happening right now in the ocean off the Pacific Northwest is consistent with the expected impact of global warming, he said.

"We can't yet prove that the ocean changes you are seeing in the Pacific are the result of global warming," Neilson said. "But there's strong evidence that long-term climate change will also result in a major increase in short-term variability, on the time frame of months, years or decades."

Global warming will cause high pressure systems and other weather phenomena to become more intense and concentrated, Neilson said, and sometimes get unusual systems locked into place for weeks or months at a time - just like the events that last winter gave Southern California drenching rains while the usually-rainy Pacific Northwest enjoyed a balmy winter.

"These climatic blocking patterns can also persist for longer periods, year after year and even for decades," Neilson said. "We see this in terrestrial weather patterns all the time. But the oceans and land are all part of the same planet, and what affects one will also affect the other."

A global oceanic "index" that measures such factors as temperature and barometric pressure showed a fundamental increase in volatility beginning with the Dust Bowl of the 1930s, Neilson said. It fluctuated in one long trend from the 1940s to 1970s, and began another pattern from the 1970s to around the present, he said. But just in the past few years, this index has once again been extremely volatile.

One possibility is that the ocean right now is becoming increasingly organized, meaning that currents and other mechanisms are shifting around in time and space to deal with and transport the increased heat they are absorbing, Neilson said. Heat always moves from the tropics to the polar regions, and during stable climate periods this process is fairly orderly and predictable. When the climate changes, Neilson said, the process is expected to become much more extreme and variable.

"The wide variability and oscillation of ocean patterns in recent years is very unusual," he said. "We may be beginning another fundamental phase change right now in how these ocean systems and circulation patterns will operate for decades to come. But we'll only know for sure later on, by looking backwards at the event." "We can't say for sure yet that this volatility is being caused by global warming," he said. "But this is exactly the type of thing you would expect to see."

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Jane Lubchenco, 541-737-5337

OSU aquaculture researc program receives $2.15 million

CORVALLIS, Ore. - The Aquaculture Collaborative Research Support Program at Oregon State University has received a $2.15 million grant from the U.S. Agency for International Development to manage global research projects involving some three dozen institutions around the world.

OSU has managed the international aquaculture program, known as CRSP, since 1982 under a number of multi-year grants.

The focus of research this year will be on aquaculture development in coastal and inland areas, according to Hillary S. Egna, the program's director. The research will emphasize production technology, watershed management, and human welfare, health and nutrition.

"We provide foreign assistance through a combination of higher education, agriculture and natural resource management partnerships," Egna said. "It is a timely pairing of U.S. expertise and goodwill."

Most of the research projects are conducted in developing countries. OSU coordinates the effort with 12 other U.S. university partners and 23 international institutions. The Aquaculture CRSP is one of nine similar projects funded by USAID that focus on nutrition and income generation through improved food production and natural resource management in Latin America, the Caribbean, Africa, Eastern Europe and Asia.

A number of the projects have applications to aquaculture, aquatic resources management, poverty elimination efforts and agribusiness in the U.S., Egna said. In one recent initiative, the OSU-run Aquaculture CRSP program partnered with the National Oceanic and Atmospheric Administration's Sea Grant program to create an international model based on Sea Grant, which is a marine research, education and outreach program. New York Sea Grant at Cornell University and Universidad Juarez Autonoma de Tabasco in Mexico are leading the effort.

Another new initiative launches a fellowship program beginning in 2005-06 that provides $5,000 awards to qualified OSU graduate students who add international dimensions to their research in aquatic resources-related fields.

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Hillary Egna, 541-737-6415

Research identifies "hot spots" of ocean productivity

CORVALLIS, Ore. - A study of barnacles on the central Oregon Coast has revealed significant "hot spots" of ocean productivity where marine life has much greater reproductive potential - information that could be a key to the successful siting of marine reserves.

Research by Oregon State University scientists showed that near Cape Perpetua, an ocean area of high primary productivity, barnacle populations produced five times as many offspring as those living near Cape Foulweather, a region of lower productivity. In controlled experiments, the scientists found an even larger effect of nearshore ocean conditions - Cape Perpetua barnacles produced more than 120 times as many babies as those in the Cape Foulweather area.

The study highlights the importance of including information on ecological processes when designing reserves and other types of marine protected areas, the scientists said. It is one of the first studies to link reproductive variation with key ecological processes on a scale that's relevant to management and conservation. The findings were published today in a professional journal, Proceedings of the National Academy of Sciences.

"This study demonstrates that not all ocean places are equivalent, and that some populations are more likely than others to contribute to future generations," said Heather Leslie, a marine ecologist at OSU. "This could serve as a model for how to link information on biodiversity patterns with underlying ecological processes."

Variability in ocean currents and bottom topography, as well as biological interactions, all can contribute to differences in the productivity of marine ecosystems. Biodiversity protection and enhancement of nearby fisheries are among the goals of marine reserves, the researchers said, and an important aspect of siting effective reserves would be understanding how the productivity of key populations vary.

"Not all ocean areas are the same, and the likelihood of fulfilling the objectives of reserves and other area-based management efforts would increase if we understand the ecological processes responsible for biodiversity patterns," Leslie said.

Integrating this information is particularly important, Leslie said, given the forecasts of changes in ocean currents and other biological and physical processes due to climate change.

Barnacles, Leslie said, have a life history similar to many other marine species and could serve as a useful model of how variation in ocean productivity affects higher trophic levels, all the way up the food chain to major fisheries. Barnacles also play an important role in rocky shore dynamics, serve as prey for many predators, provide habitat for other organisms and help some species such as mussels get established.

Using these barnacles as an indicator of larger processes, this research demonstrated that variation in primary productivity and other key processes can translate into significantly greater or lesser reproductive potential. The barnacles at Cape Perpetua produced many more offspring, both individually and per unit area. The higher productivity, researchers say, is probably linked to the wider continental shelf and more complex bottom topography near Cape Perpetua.

"Scientists have traditionally assumed that ocean conditions were fairly uniform on the scale of tens or hundreds of miles," Leslie said. "We know now that isn't the case. There are very significant differences in the productivity of marine populations in areas even a few miles apart."

This research is part of the work being done through PISCO, the Partnership for Interdisciplinary Study of Coastal Oceans, and was supported by grants from the David and Lucile Packard Foundation, the Andrew W. Mellon Foundation, and the National Science Foundation. PISCO focuses on understanding the nearshore ecosystems of the West Coast of the United States through interdisciplinary research, student training and outreach programs.

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Jane Lubchenco, 541-737-5337

Oregon's tsunami warning signs go global

CORVALLIS - The illustration shows a big wave and a figure running up a steep hill. The message is clear: when a tsunami is about to hit the coast, head for high ground.

The illustration, created by Oregon State University Extension Service designer Tom Weeks, has been displayed on the Oregon coast for many years as part of the state's tsunami warning system.

Now Weeks' illustration is being used to warn coastal residents around the world, providing unmistakable instructions in the universal language of pictures.

The tsunami warning illustration is one in a series of communication graphics Weeks developed as part of OSU's efforts to help people move quickly to safety in the event of an earthquake or tsunami. Other illustrations graphically identify tsunami hazard zones, evacuation routes and assembly areas. The signs have been adopted in other Pacific coastal states - Washington, California, Alaska, and Hawaii - as part of the National Tsunami Hazard Mitigation Program, a collaborative state-federal program to improve tsunami warning systems and public awareness.

Jim Good, an OSU Extension Sea Grant scientist, developed the tsunami sign concepts with state geologists and planners and worked with Weeks on the illustration designs.

Following the Indian Ocean tsunami last winter, Good's graduate student, Somrudee Meprasert, went to Thailand to serve on a tsunami assessment group and she took copies of the signs with her to share with Thai officials. In May, Weeks' illustration was posted on new warning signs along Thai beaches as part of Thailand's new National Disaster Warning Centre.

"Extension Sea Grant's leadership and Tom's clear, unambiguous design will now save lives around the world, not just in the United States," Good said.

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Jim Good, 541-737-1339

OPAN to broadcast tsunami presentation

CORVALLIS - The Oregon Public Affairs Network, or OPAN, will broadcast a lecture with video and slides by Eddie Bernard, a tsunami expert with the National Oceanic and Atmospheric Administration, on Thursday, July 7.

The lecture, "The December 2004 Asian Tsunami: Lessons Learned for Improved Tsunami Preparedness," was originally given on the Oregon State University campus in May as part of the John Byrne lecture series, sponsored by Oregon Sea Grant and the OSU College of Oceanic and Atmospheric Sciences.

Bernard is director of the NOAA Pacific Marine Environmental Laboratory, in Seattle.

OPAN is broadcast on channel 27 in Corvallis, Philomath, and Lewisburg. The Bernard lecture will begin at 6 p.m. Other channels and times can be located online at www.opan.org.

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Larry Pribyl, 541-737-3817

OSU Scientists Detect Low-Oxygen Zones Forming Off Coast for Sixth Straight Year

CORVALLIS, Ore. – A team of Oregon State University scientists monitoring near-shore ocean conditions off Oregon says that oxygen levels in the lower water column have plummeted, thrusting the region into a hypoxic event for the sixth consecutive year.

Hypoxia can lead to significant marine die-offs, the researchers say, depending on the severity, duration and location of the low-oxygen zone.

Although conditions this summer have not yet duplicated the severity of the historic hypoxic event of 2006, the outlook for the remainder of the summer and early fall is uncertain. Measurements taken by the OSU scientists in late June mirrored those of last year, but a shift to a southerly wind pattern in mid-July pushed the mass of low-oxygen water away from the shoreline. A sizeable mass of low-oxygen water remained, however, across much of the shelf from Florence to Newport.

Last week, the winds shifted again and these northerly winds pulled the larger mass of hypoxic water back closer to shore, where it may endanger reef-dwelling sea creatures that have limited mobility.

“We are definitely experiencing hypoxia once again,” said Francis Chan, a marine ecologist with OSU and the Partnership for Interdisciplinary Studies of Coastal Oceans, or PISCO. “By the beginning of July, conditions were approaching what we consider ‘severe.’ But unlike last year, a shift in wind patterns in mid-July pushed low oxygen waters offshore and gave us a temporary reprieve.

“The winds have shifted yet again,” Chan added, “and we are now tracking to see how much further oxygen levels will drop. It is a dynamic system with a lot of uncertainty, which illustrates the need for more research and monitoring of these conditions.”

The OSU researchers say the region has not yet fully recovered from last year’s historic hypoxia. Video monitoring of reefs off the central Oregon coast that were affected by last year’s hypoxia show a significant loss of species diversity. Most species of sea stars, sea cucumbers and many bottom-dwellers are still absent, said Jane Lubchenco, the Wayne and Gladys Valley Professor of Marine Biology at OSU.

“Some rockfish have moved into the area, but the bottom-dwellers that provide the habitat and food for rockfish and a diverse array of other species, are slow to return,” Lubchenco said. “The system is showing early signs of rebounding, but a full recovery may be a long way off. This marine ecosystem may take as `long to recover as the terrestrial ecosystem did from the eruption of Mount St. Helens.

“Moreover, the current low oxygen conditions may knock the system back to the starting line, delivering another setback to an already stressed system,” Lubchenco added.

Last year, the largest and most devastating hypoxic conditions ever observed off the Pacific Northwest coast began with low oxygen levels of 0.5 milliliters per liter of water in July off Cape Perpetua – identical to what the OSU researchers observed this year. During the next two months, strong upwelling-favorable winds persisted, fueling massive phytoplankton blooms, which eventually died and sank to the bottom, leading to some of the lowest oxygen levels ever recorded and killing a variety of marine life off the Pacific coast.

For the first time, some areas of the ocean actually ran out of oxygen altogether, the researchers said.

“The 2006 situation was not only the strongest, most widespread hypoxia event yet seen off the Pacific Coast – it also was the most long-lasting,” Chan said. “The oxygen levels were off the charts and they continued through the end of October.

“We have seen nothing to suggest that conditions this summer will be any different,” Chan added. “In fact, it is eerily similar to last year.”

The OSU scientists have been monitoring offshore conditions this year since April, deploying instruments, taking survey cruises and working with the Oregon Department of Fish and Wildlife on video surveillance of reefs affected by last year’s hypoxia. By the end of June 2007, the oxygen levels on those reefs had decreased dramatically, to an average of 0.5 milliliters per liter. Any level of dissolved oxygen below 1.4 milliliters is considered hypoxic for most marine life; a normal midsummer reading may range from 1.5 to 3.0 milliliters.

The next few weeks are critical, says Jack Barth, a professor of physical oceanography at OSU. If upwelling-favorable winds are strong and persistent, the already-low oxygen levels may continue to decline to dangerous levels.

“Last year, summer winds were more intense than normal, and led to upwelling that was twice as strong as usual,” Barth said. “Summer upwelling winds are a vital part of the system, but they can become too much of a good thing. Strong and persistent upwelling winds fuel intense biological production, leading to hypoxia in near-bottom waters as plankton sink and decompose at depth.

Barth said it is too early to say with any certainty that the ongoing hypoxic conditions are a direct result of global warming, but adds that the symptoms are consistent with global warming models.

“There are many variables such as the Pacific Decadal Oscillation that seem to run in 10- to 15-year cycles,” Barth pointed out. “But this marks the sixth consecutive year that we have documented significant hypoxia and observed changes in the circulation and winds that may be responsible.”

The OSU-led research team is enlisting a number of other resources in collecting dissolved oxygen data in near-shore waters as it seeks to determine the extent of hypoxia along the West Coast. Stephen Pierce, an OSU oceanographic research associate, is aboard a vessel that is conducting a biannual hake survey for the National Marine Fisheries Service (NMFS). He’ll be testing water samples for dissolved oxygen from Monterey, Calif., to Vancouver Island.

Already, Pierce and his colleagues have just discovered hypoxic waters with oxygen levels of about 0.75 milliliters per liter in the near-shore from Coos Bay to Florence. These are some of the first recent recordings of hypoxic water along the southern Oregon coast, which has not been well-monitored, and will provide important baseline data for the future.

Researchers including NOAA’s Bill Peterson, who works at OSU’s Hatfield Marine Science Center in Newport, are taking dissolved oxygen measurements while conducting a Bonneville Power Administration-sponsored salmon survey off the Oregon and Washington coast.

OSU scientists also are working with the Olympic Coast National Marine Sanctuary and researchers at the University of Washington to expand hypoxia detection efforts up through the northern Washington coast.

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Francis Chan,
541-737-9131

Beach Erosion Experts from Around the World Gather at OSU for Conference

CORVALLIS, Ore. – Beach erosion experts from around the world will gather at Oregon State University July 30 to Aug. 3 for a conference to share information on the mystery of coastal dynamics – and the influence that global climate change may have on our coastlines.

More than 40 scientists from seven countries will spend the week discussing research and management strategies related to a network of beach observation systems called Argus Stations.

Coastal erosion is a problem for more than 70 percent of the shores in the United States, experts say, and rising sea levels will exacerbate the problem. Since more than half of the people in the U.S. live within 50 miles of the ocean, conflicts over erosion and what to do about it are increasing in scope and intensity, said Robert Holman, a professor in OSU’s College of Oceanic and Atmospheric Sciences and an organizer for the event on campus.

The conference at OSU will bring together collaborators for the Argus Program – an international network of researchers who operate monitoring stations around the world to study beach erosion and dynamics. Much of the conference will be technical in nature, Holman said, and focus on the technology that allows the researchers to take hourly measurements and images of beaches around the world, transmit them to OSU’s Coastal Imaging Lab for evaluation, and turn them into new understanding.

The scientists also will discuss new issues in coastal dynamics and management decisions that have been influenced by the science, ranging from coastal development to preparation for inundation from tsunamis and hurricane surges.

“Our knowledge of coastal dynamics was quite limited early on,” Holman said. “We thought that understanding the basic nature of simple fluid mechanics would be enough to allow us to manage our coasts successfully. But nature proved us wrong. We now know through long-term observation that the mixture of sand and waves, at what we call beaches, is rich in complexity and spawns complicated sandbars, rich channels and other characteristics that continually change.”

The Argus Program began as a simple research project developed at OSU’s Coastal Imaging Lab, using a fixed camera on a bluff near Newport, Ore., to systemically monitor that section of the coastline, said Holman, who was principal investigator for the study. It has since evolved into a sophisticated operation involving more than 100 scientists worldwide.

Argus has become an important new tool for coastal zone management in Australia and Europe, with new stations established in England, The Netherlands, Spain, France and Italy. Argus stations also operate in Brazil, New Zealand, Japan and the United States.

The systematic, long-term images taken by Argus instruments have changed the way scientists look at beach processes, and improved the data that coastal managers have for making decisions.

“This is really a case where technology and long-term observations have made a huge difference in how we view the coastline,” Holman said. “We’ve known for a long time that beaches erode in the winter and build up in the summer. But the monthly and even daily changes that take place – from tides, storms, offshore currents, and winds – has been eye-opening.

“It’s more than a curiosity factor for scientists,” he added. “These processes can create deadly rip currents that take lives, they can erode entire beaches and plunge houses down cliffs, they can make boating extremely hazardous – there are numerous implications. Understanding the complexity of these dynamic areas is critical.”

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Rob Holman,
541-737-2914

Seashore North of Columbia River Faces Major Erosion

PORTLAND, Ore. – Some of the most dramatic beach erosion in the Pacific Northwest during the next 20 years may take place just north of the Columbia River jetty, where a century of shore building has ended and a major shift toward erosion has been identified.

This new trend, which scientists now believe began a few decades ago and is one of the more extreme examples of the dynamic and constantly changing Pacific Northwest seashore, was described today by a geoscientist from Oregon State University at the Coastal Zone 2007 conference in Portland.

Researchers predict that by the year 2020, the shore areas for about six miles north of North Head – a large outcropping south of Seaview and Long Beach – may retreat between 100 and 300 meters, depending on several variables. Large areas of land that have been created in the past 100 years are now going to be reclaimed by the ocean.

“The Pacific Northwest ocean beaches are spectacular systems, with constant change, new sand dunes forming and disappearing, so on one level this is not all that unusual,” said Peter Ruggiero, an OSU assistant professor of geosciences. “In this case, we can trace the forces at work directly to the creation of the Columbia River jetties about a century ago.”

Those jetties were built beginning in the 1890s and designed to create a more workable channel for navigation, and have in fact helped address many problems on what was once considered the “Graveyard of the Pacific,” an area of the Columbia River bar that has claimed more than 2,000 vessels and 700 lives. But in the process, the jetties and multiple dams on the river have vastly changed sediment transport processes in ways that are still being worked out.

In this case, the original construction of the jetties cut in half an “ebb tidal delta,” a vast shoal of sand off the mouth of the Columbia River. The changed interaction of river and tidal currents, ocean waves and sediment transport resulted in decades of shore accretion both north and south of the jetties, sometimes adding as much as 10-20 yards a year of new land.

Now, that process has reversed in some areas, and one of those particularly hard hit will be the region just north of the jetty, the very southwestern tip of Washington state. Erosion projections have already caused some development plans to be reconsidered, Ruggiero said, and many public and policy agencies need to be made more fully aware of just how extreme the erosion may be within the next 15 years.

The erosion will affect the first few miles just north of the jetty, Ruggiero said, and studies suggest that remaining shore areas on the Long Beach peninsula will continue to build outward, rather than erode.

Benson Beach between the Columbia River north jetty and North Head, part of Fort Canby State Park, began eroding a few decades ago, Ruggiero said. This has had a significant impact on park campgrounds and new development plans based on the anticipated erosion have been developed.

Beginning in the 1990s, erosion continued past North Head, and for the first time is occurring in front of the coastal communities of Seaview and Long Beach. The newest OSU projections indicate this trend will continue northward, but by 2020 will still only be affecting the first six miles north of the jetty. Erosion may continue beyond that date, Ruggiero said, but existing computer models are not precise enough to make such projections.

“On average we’re predicting about 200 meters of inland erosion in this area, but there are a lot of variables,” he said. “These projections could change based on climate change and variability, increases in wave height, even the dredging and placement of sand done by the Army Corps of Engineers.”

Ultimately, the erosion of the area north of the Columbia River north jetty is linked to erosion of a submerged sand body named Peacock Spit. This submerged spit, a remnant of the ebb tidal delta, has been lowering for decades after the construction of the jetty. Eventually, the lowering of the offshore seabed allowed larger waves to hit closer to shore, eroding the beach. There is also simply less material available to feed beaches to the north.

Since before human settlement, Ruggiero said, the Columbia River has been a driving force that shapes the beaches of both Oregon and Washington. Before the era of dam construction, seasonal floods would dump 5-10 million cubic yards of sand a year into the system, and lower sea levels at times in the past helped Columbia River sediments to form the basis for much of the Pacific Northwest coastal zone.

Although tamed by dams, stored sediments and reduced floods, peak river flow still determines how much sand is transported to the river mouth and adjacent ocean beaches. Researchers are still learning how much of 4.5 million cubic yards of sand dredged each year from the river mouth is due to the erosion of shoals fed by floods of long ago, and how much comes from the modern estuary.

What researchers do know is that the amount dredged is a comparatively large amount of sand, and they are urging constructive use of 100 percent of the material dredged from the river and bar, instead of dumping portions of it in the deeper ocean.

The OSU presentation at the Portland conference represents ongoing work that is one part of a national effort, largely supported by the U.S. Geological Survey, to better understand coastal hazards and changes on all United States seashores. Previous reports have already been finished on East Coast and Gulf of Mexico beaches, Ruggiero said. In the Pacific Northwest, scientists are trying to track changes since the late 1880s, and also devoting special attention to changes in the past few decades.

Coastal changes can be driven by storms, hurricanes, seasonal cycles, waves, ocean currents, sediment deposition, and many other factors. Long-term climate change and more temporary phenomena such as El Nino and La Nina can also play important roles. In general, Oregon coastal areas are significantly affected by major storm events, while Washington beach changes appear more linked to long-term trends. But the discussion, Ruggiero said, also always seems to come back to the Columbia River and the management operations under way on it.

“Some important changes in using dredged sediments, for instance, were made in the 1970s, but there’s still more we can do,” Ruggiero said. “Part of what’s interesting just lately, and very positive, is to see all the parties at the same table, really working out these issues, people from state and federal governments, agency managers, coastal communities, scientists, the fishing industry.”

“Not long ago after a discussion at one meeting I saw a government official laughing and slapping high fives with a crab fisherman,” Ruggiero said. “That’s not something you see real often.”

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Peter Ruggiero,
541-737-1239

Influx of Cool-Water, Fatty Copepods Bodes Well for Salmon, Sablefish

NEWPORT, Ore. – The early arrival of subarctic zooplankton – including unusually high numbers of copepod species rarely seen in Oregon – is providing a smorgasbord for offshore salmon and other species of fish, according to researchers conducting a salmon survey from Newport, Ore., to LaPush, Wash.

This is the 10th year researchers have conducted the survey of juvenile salmon and preliminary results suggest that numbers of both juvenile coho and juvenile Chinook surveyed this spring were the highest they’ve recorded.

“We’ll know more when we crunch the final numbers, but it certainly looks like a banner year for salmon survival – primarily because of a bountiful supply of the right kind of food,” said Bill Peterson, a fisheries biologist with NOAA who is based at Oregon State University’s Hatfield Marine Science Center in Newport.

The juvenile salmon surveys, conducted in May, June and September, include the waters from the central Oregon coast north to the tip of Washington state.

Based on a long-term ocean observing program, which Peterson initiated off Newport in 1996, it has become clear that juvenile salmon respond quickly to changing ocean conditions.

“When the ocean is in a cool phase, such as existed from 1999 to 2002, juvenile salmon survival was high and adult returns were very high one year later for coho, and two years later for Chinook,” said Peterson, a courtesy professor in OSU’s College of Oceanic and Atmospheric Sciences. “After ocean conditions suddenly changed in autumn 2002 to a warm phase, salmon returns immediately began to decline.”

The ocean off Oregon has begun to cool once again, starting in July of 2006, after nearly four years of warm ocean conditions, said Peterson. Cooler waters bring northern species of copepods into the region to feast on phytoplankton blooms triggered by summer upwelling. Copepods are small crustaceans that are major links in the food chain that supports salmon, other fish, whales and seabirds. Peterson’s research suggests that northern species – which are lipid rich – provide better nutritional benefits for their consumers than southern copepod species that are prevalent during warm water regimes.

“This year, we’ve experienced one of the earliest biological transitions to ‘summer’ conditions in recent decades,” Peterson said. “The subarctic zooplankton not only arrived extremely early, we are seeing unusually high numbers of a group of copepod species rarely seen off Oregon. These copepods are bigger than our usual ‘local’ species, and pack on even more lipids.

“The transition began in March this year, the earliest we’ve recorded during the 12 years of observations made off Oregon,” Peterson added. “The two other years when the zooplankton arrived anywhere near that early – in 1970 and 1972 – were characterized by very high salmon production.”

Among the seldom seen copepod species visiting Oregon this year are Neocalanus plumchrus, flemingerii, and Neocalanus cristatus.

“Whether this means we’re experiencing a greater influx of subarctic water than usual, or whether we’re getting normal water transport that happens to have a greater abundance of copepods – we don’t know,” Peterson said. “In either case, it’s good news for the fish that feed on them, particularly some species of groundfish and sablefish (black cod), which target Neocalanus.

“Of course,” Peterson added, “we must see how the ocean responds during the remainder of the summer months before offering more firm prognostications.”

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Bill Peterson,
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