OREGON STATE UNIVERSITY

marine science and the coast

Climate change, population growth may lead to open ocean aquaculture

CORVALLIS, Ore. – A new analysis suggests that open-ocean aquaculture for three species of finfish is a viable option for industry expansion under most climate change scenarios – an option that may provide a new source of protein for the world’s growing population.

This modeling study found that the warming of near-shore surface waters would shift the range of many species toward the higher latitudes – where they would have better growth rates – but even in areas that will be significantly warmer, open-ocean aquaculture could survive because of adaptation techniques including selective breeding.

Results of the study are being published this week in the Proceedings of the Royal Society B.

“Open-ocean aquaculture is still a young and mostly unregulated industry that isn’t necessarily environmentally sound, but aquaculture also is the fastest growing food sector globally,” said James Watson, an Oregon State University environmental scientist and co-author on the study. “One important step before developing such an industry is to assess whether such operations will succeed under warming conditions.

“In general, all three species we assessed – which represent species in different thermal regions globally – would respond favorably to climate change.”

Aquaculture provides a primary protein source for approximately one billion people worldwide and is projected to become even more important in the future, the authors say. However, land-based operations, as well as those in bays and estuaries, have limited expansion potential because of the lack of available of water or space.

Open-ocean aquaculture operations, despite the name, are usually located within several miles of land – near enough to market to reduce costs, but far enough out to have clean water and less competition for space. However, aquaculture managers have less control over currents, water temperature, and waves.

To assess the possible range for aquaculture, the researchers looked at three species of fish – Atlantic salmon (Salmo salar), which grows fastest in sub-polar and temperate waters; gilthead seabream (Sparus aurata), found in temperate and sub-tropical waters; and cobia (Rachycentron canadum), which is in sub-tropical and tropical waters.

“We found that all three species would shift farther away from the tropics, which most models say will heat more than other regions,” said Dane Klinger, a former postdoctoral researcher at Princeton University and lead author of the study. “Production of Atlantic salmon, for example, could expand well into the higher latitudes, and though the trailing edge of their range may face difficulties, adaptation techniques can offset those difficulties.

“Further, in most areas where these species are currently farmed, growth rates are likely to increase as temperatures rise.”

Open-ocean aquaculture is not without risk, the researchers acknowledge. The recent escape of farmed Atlantic salmon in Washington’s Puget Sound alarmed fisheries managers, who worry that the species may breed with wild Chinook or coho salmon that are found in the Pacific Northwest. Introduced species and populations also have the potential to introduce disease to native species. “A key unresolved question is how large the industry and individual farms can become before they begin to negatively impact surrounding ecosystems,” Klinger said.

The authors say their modeling study was designed to assess the potential growth rates and potential range for the three fish species, based on climate warming scenarios of 2-5 degrees Celsius (or 3.6 to 9 degrees Fahrenheit).

The study also found:

  • Seabream will have the greatest potential for open-ocean farming in terms of area, but the fish will grow at a slower rate than with salmon or cobia;
  • Cobia has the second largest potential area for growth, just ahead of salmon;
  • For all species, depth of water is the greatest constraint to development, followed by suitable currents;
  • Other factors dictating success include environment, economics (feed, fuel and labor), regulations and politics, ecology (disease, predators, and harmful algal blooms), and social norms.

“Offshore aquaculture will continue to be a small segment of the industry in the near-term, but there is only so much you can do on land and there are not enough wild fish to feed the world’s population,” Watson said. “Assessing the potential is the first step toward reducing some of the uncertainties for the future.”

Watson, who is on the faculty of OSU’s College of Earth, Ocean, and Atmospheric Sciences, did his research while at Princeton University.

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James Watson, 541-737-2519, jrwatson@coas.oregonstate.edu;

Dane Klinger, dhklinger@stanford.edu

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Study: Sunlight and the right microbes convert Arctic carbon into carbon dioxide

CORVALLIS, Ore. – Nearly half of the organic carbon stored in soil around the world is contained in Arctic permafrost, which has experienced rapid melting, and that organic material could be converted to greenhouse gases that would exacerbate global warming.

When permafrost thaws, microbial consumption of those carbon reserves produces carbon dioxide – much of which eventually winds up in the atmosphere, but scientists have been unsure of just how the system works.

A new study published this week in Nature Communications outlines the mechanisms and points to the importance of both sunlight and the right microbial community as keys to converting permafrost carbon to CO2. The research was supported by the U.S. National Science Foundation and the Department of Energy.

“We’ve long known that microbes convert the carbon into CO2, but previous attempts to replicate the Arctic system in laboratory settings have failed,” noted Byron Crump, an Oregon State University biogeochemist and co-author on the study. “As it turns out, that is because the laboratory experiments did not include a very important element – sunlight.

“When the permafrost melts and stored carbon is released into streams and lakes in the Arctic, it gets exposed to sunlight, which enhances decay by some microbial communities, and destroys the activity for other communities. Different microbes react differently, but there are hundreds, even thousands of different microbes out there and it turns out that the microbes in soils are well-equipped to eat sunlight-exposed permafrost carbon.”

The research team from Oregon State and the University of Michigan was able to identify compounds that the microbes prefer using high-resolution chemistry and genetic approaches. They found that sunlight makes permafrost soils tastier for microbes because it converts it to the same kinds of carbon they already like to eat – the carbon they are adapted to metabolize.

“The carbon we’re talking about moves from the soil into rivers and lakes, where it is completely exposed to sunlight,” Crump said. “There are no trees and no shade, and in the summer, there are 24 hours a day of sunlight. That makes sunlight potentially more important in converting carbon into CO2 in the Arctic than in a tropical forest, for example.”

As the climate continues to warm, there are interesting ramifications for the Arctic, said Crump, who is a faculty member in OSU’s College of Earth, Ocean, and Atmospheric Sciences.

“The long-term forecast for the Arctic tundra ecosystem is for the warming to lead to shrubs and bigger plants replacing the tundra, which will provide shade from the sunlight,” Crump said. “That is considered a negative feedback. But there also is a positive feedback, in that seasons are projected to expand. Spring will arrive earlier, and fall will be later, and more water and carbon will enter lakes and streams with more rapid degradation of carbon.

“Which feedback will be stronger? No one can say for sure.”

The stakes are high, Crump said. There is more carbon stored in the frozen permafrost than in the atmosphere. It has accumulated over millions of years by plants growing and dying, with a very slow decaying process because of the freezing weather.

“Some of the organic matter is less tasty to microbes than others,” Crump said, “but bacterial communities are diverse, so there will be something out there that wants that energy and will use it.”

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Byron Crump, 541-737-4369, bcrump@coas.oregonstate.edu

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When Arctic permafrost melts, it seeps into streams and lakes where it is exposed to sunlight, starting the process of converting it to carbon dioxide.

 

Collaborative project between researchers, fishermen aims to reduce West Coast seabird bycatch

ASTORIA, Ore. – A collaborative project between researchers and the West Coast sablefish fishing industry is showing promise for reducing the number of seabirds caught in longline fishing gear, in particular several albatross species including one threatened with extinction.

The combination of using streamer lines (also called bird-scaring lines) to protect longline fishing gear from seabird attacks on baits, and setting hooks at night when the birds are less active can significantly reduce seabird mortality, the researchers say.

Results of the study were just published in the journal Fisheries Research.

“The project was a great example of collaboration between researchers and industry,” said Amanda Gladics, a coastal fisheries specialist with the Oregon Sea Grant program based at Oregon State University and lead author on the study. “The fishermen invited us out onto their boats and provided us with a lot of insights.

“It was their idea for us to explore whether fishing at night could prevent albatross bycatch on the U.S. West Coast – and it turned out, that was the case. We were thrilled to find that albatross bycatch could be reduced without increasing bycatch of other non-target species or reducing target catch, as can sometimes occur.”

Incidental mortality of seabirds in longline fisheries has been an international conservation concern for decades, with estimates of 160,000 seabirds killed in longline fisheries annually. With 15 of 22 species threatened with extinction, albatrosses are especially vulnerable to bycatch mortality. They don’t begin breeding until they are five to 10 years of age and produce only one egg every year or every other year, Gladics said.

“Most of the mortality takes place when the birds attempt to forage on the baited hooks when fishermen deploy longlines,” she said. “In addition to the environmental impacts, there can be an economic cost as well. Losing baits to birds can be costly, and serious economic harm can occur if excessive seabird bycatch triggers a fishery closure.”

The sablefish industry in Alaska addressed the problem in part through the use of streamer lines, which are the most commonly used seabird bycatch mitigation measure worldwide. The technique runs a 300-foot line from the vessel’s mast or another high part of the vessel to a towed object like a float. A series of rubber tubes hanging down every 15 feet or so creates a visual barrier that prevents birds from attacking the bait.

However, there is a catch, the researchers discovered.

Some fishing boats use floats to keep their baits off the seafloor to conserve baits and protect their catch from damage caused by scavengers. For those that did use floats, streamer lines were less effective at preventing seabird attacks. In fact, albatross attack rates were 10 times higher on longlines with floats compared to those without.

“Using floats puts the longline more than twice as far behind the boat before it sinks beyond the diving range of albatrosses – to the point where bird-scaring lines just don’t reach,” Gladics said. “With the hooks at the surface for longer, the birds have more time to hone in on the bait.”

Gladics said some of the West Coast sablefish boats reported that they already fished at night to prevent bird attacks and fishermen suggested that night fishing should be explored as a seabird bycatch mitigation option for the fleet.

In response the authors examined over a decade of data collected by NOAA Fisheries at-sea observers, and found that when hooks were set at night, after civil dusk, albatross bycatch was 30 times lower and target catch was almost 50 percent higher compared with daytime fishing – a classic win-win, the researchers said.

“The combination of night fishing for vessels that use floats or going without floats on the longlines and using bird-scaring lines provide two options for helping fishermen reduce bycatch,” she said. “However, a single ‘one size fits all’ solution won’t work for all fishermen and all boats, so developing multiple seabird avoidance options that are specific to the region is crucial – and that requires collaboration between researchers and fishermen.”

The research was funded by The National Fish and Wildlife Foundation, David and Lucile Packard Foundation, NOAA Fisheries, Washington Sea Grant and Oregon Sea Grant.

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Amanda Gladics, 503-325-8573, Amanda.Gladics@oregonstate.edu

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(Photo at left is available at: https://flic.kr/p/YNwkVj)

 

 

 

 

 

 

 

 

 

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Amanda Gladics

Country’s largest estuary facing increasing acidification risk

CORVALLIS, Ore. – Chesapeake Bay, the largest estuary in the United States and one of the largest in the world, is facing new risks from a layer of highly acidified water some 10 to 15 meters below the surface, a new study has found.

This “pH minimum zone” is 10 times more acidic than the bay’s surface waters and may pose a risk to a variety of economically and ecologically important marine species, including oysters, crabs and fish, the researchers say. A decline in the number of calcium carbonate-shelled organisms – particularly oysters – may be hampering the bay’s ability to deal with the increase in acidity, they add.

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

“Oysters and other bivalves provide a built-in Tums effect that naturally helps the bay deal with corrosive water,” said George Waldbusser, an Oregon State University marine ecologist and co-author on the study. “They generate large amounts of calcium carbonate structures, which may be able to buffer the increasing amounts of carbon dioxide entering the bay.

“Overharvesting and disease have reduced the number of oysters, however, and we’re seeing the results.”

Lead author Wei-Jun Cai from the University of Delaware led the study, which found pH levels in this stratified layer of water to be about 7.4, nearly a unit lower than surface waters where the average pH is about 8.2. A combination of factors likely caused this corrosive zone, including hypoxia and generation of toxic hydrogen sulfide in the bottom waters mixing with other layers of the bay.

“This study shows for the first time that the oxidation of hydrogen sulfide and ammonia from the bottom waters could be a major contributor to lower pH in coastal oceans and may lead to more rapid acidification in coastal waters compared to the open ocean,” Cai said.

Previous studies, including work by Waldbusser, have shown that agricultural nutrients entering Chesapeake Bay have progressively depleted oxygen levels in the bottom waters – a process known as hypoxia – as well as acidifying the bay more quickly than offshore ocean waters. Animals need oxygen to live and without it, they die. Bacteria, however, can “breathe” without oxygen, often producing hydrogen sulfide, which further increases oxygen demand and also enhances acidification, Waldbusser said.

“Hypoxia in this case leads to an amplification of acidification,” he pointed out. “If more oysters were there, they would help pull the food out of the water, reduce oxygen demand, and sequester carbon from the system. Now the acidification is such that we have to be concerned that it will make it harder for some marine organisms to produce their calcium carbonate shells. We don’t yet know what those thresholds are all around.”

Oysters have been shown to be sensitive to changes in acidifications, particularly on the West Coast where corrosive waters severely affected the industry several years ago. Waldbusser and OSU colleague Burke Hales helped growers mitigate the issue by identifying times of the day when local acidification levels were lower so hatcheries could draw in more favorable waters to use in raising their oysters.

East Coast oysters are a different variety, Waldbusser said, and may actually be somewhat more resilient than the West Coast’s Pacific oysters. But scientific understanding of how much acidity they can withstand is limited.

“We know that in some areas of Chesapeake Bay where there has been high acidity, oysters have survived, but we don’t know if there are sub-populations that have more resilience, or what the threshold is for their ability to create shells.”

Waldbusser said individual oysters can filter upwards of 50 gallons of water each day. Researchers have estimated that prior to European settlement, Chesapeake Bay had so many oysters that they could filter the entire bay in three days. Today, it would take roughly 300 days because of fewer oysters and more nutrients in the water, he said.

“Dredging of the bay in the 1950s and 1960s removed a lot of oyster shells that formed a base for creating oyster reefs,” said Waldbusser, who began his research on oysters and acidification at the University of Maryland more than 10 years ago before coming to Oregon State.

“Since the 1980s, many of the restaurants on the East Coast participated in a program to recycle oyster shells into the bay to create more habitat, but it hasn’t been enough to replace what has been take out.”

Waldbusser is on the faculty of OSU’s College of Earth, Ocean, and Atmospheric Sciences.

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George Waldbusser, 541-737-8964, waldbuss@coas.oregonstate.edu

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Study: Methane from tundra, ocean floor didn’t spike during previous natural warming period

CORVALLIS, Ore. – Scientists concerned that global warming may release huge stores of methane from reservoirs beneath Arctic tundra and deposits of marine hydrates – a theory known as the “clathrate gun” hypothesis – have turned to geologic history to search for evidence of significant methane release during past warming events.

A new study published this week in the journal Nature suggests, however, that the last ice age transition to a warmer climate some 11,500 years ago did not include massive methane flux from marine sediments or the tundra. Instead, the likely source of rising levels of atmospheric methane was from tropical wetlands, authors of the new study say.

While this certainly is good news, the study also points at a larger role of humans in the recent methane rise, noted Edward Brook, an Oregon State University paleoclimatologist and co-author on the study

“Our findings show that natural geologic emissions of methane – for example, leakage from oil seeps or gas deposits in the ground – are much smaller than previously thought,” Brook said. “That means that a greater percentage of the methane in the atmosphere today is due to human activities, including oil drilling, and the extraction and transport of natural gas.”

The study suggests that human emissions of geologic methane may be as much as 25 percent higher than previous estimates. Although not as abundant as carbon dioxide, methane is a much more powerful greenhouse gas and therefore the rising levels are an important contributor to global warming.

“This means we have even more potential to fight global warming by curbing methane emissions from our fossil fuel use,” said Vasilii Petrenko, an associate professor of earth and environmental sciences at the University of Rochester, and lead author on the study.

Anthropogenic methane emissions are the second largest contributor to global warming after carbon dioxide, but there has been uncertainty as to the source of that methane and whether it has changed over time, Brook noted. The new study sheds light on the issue by analyzing levels of atmospheric methane from the last deglaciation in air bubbles that have been trapped in pristine ice cores from Antarctica’s Taylor Glacier.

The researchers were able to estimate the magnitude of methane emissions from roughly 11,500 years ago by measuring radioactive carbon isotopes in methane, (carbon-14, also known as 14C or radiocarbon), which decay fairly rapidly. Methane released from those marine hydrates and permafrost is old enough that any 14C originally present has now decayed away.

They found that amount of methane from ancient “14C-free sources” was very low – less than 10 percent of the total methane – during the entire range of sampling, from 11,800 to 11,300 years ago.

“A lot of people have painted the Arctic as a methane time bomb,” Brook said, “but this shows that it may be more stable than we thought. Past performance isn’t always a predictor of the future, but it is a good analog. We should be more concerned about anthropogenic sources of methane into the atmosphere, which continue to increase.”

The levels of 14C in the ice cores suggest that the increase in methane during the last deglaciation had another source – likely from tropical wetlands, said Christo Buizert, an Oregon State University researcher and co-author on the paper.

“Methane is not stored in the tropics for long periods of time, but produced every day by microbial activity in wetlands,” Buizert said. “We know from other studies that rainfall increased in the tropics during the last warming period, and that likely created more wetlands that produced the additional methane.”

Atmospheric methane has increased from 750 parts per billion in the year 1750 to more than 1,800 parts per billion today – mostly from anthropogenic sources, especially leakage from fossil fuel production, the creation of rice paddies, and cattle ranching, the researchers say.

“All of the natural gas that we mine is very old and leaking inevitably occurs during that process,” Brook said. “Natural gas is considered a cleaner energy source than coal, but it can be a significant problem depending on how much of the methane is leaking out.”

The key to documenting the source of atmospheric methane is the pristine ice cores of Taylor Glacier in Antarctica, where dry, windy conditions have allowed this ancient ice to be slowly brought to the surface. One reason scientists had yet to pin down the sources of methane during the last ice age is that the amount of 14C is so small, it takes enormous amounts of ice to get enough air to measure the isotope.

In fact, it takes some 2,000 pounds of ice, running a melting instrument over three days, to get enough air to produce one sample of measurable 14C. Drilling down in the center of the ice sheet to find that much ice from the end of the last ice age would be prohibitively costly and labor-intensive, but the unique conditions at Taylor Glacier – pushing that old ice toward the surface – made it possible.

Brook and Buizert are on the faculty of OSU’s College of Earth, Ocean, and Atmospheric Sciences

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Ed Brook, 541-737-8197, brooke@geo.oregonstate.edu;

Christo Buizert, 541-737-1572, buizertc.science.oregonstate.edu

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Taylor Glacier in Antarctica

Are blue whales finding new "microphone channel" to communicate in?

NEWPORT, Ore. – For the past two decades, scientists have documented a gradual lowering of the frequency of blue whale calls and they haven’t been sure why – or even whether the phenomenon is intentional.

Other baleen whales in the North Pacific have been recorded in recent years generating vocalizations that are missing the “overtone” portions of their calls. Again, scientists are unsure why.

A new study published this week in Scientific Reports may shed some light on these mysteries. A group of acoustic researchers at Oregon State University’s Hatfield Marine Science Center recorded a blue whale call, then created a model to replicate that sound based on a series of controlled air bursts from the animal’s vocal cords.

In other words, they showed that whales can control the frequency of their calls by blowing air through their vocal cords at a faster or slower rate.

“Our study shows that blue whales in particular – and perhaps other baleen whales in general – may be making their harmonious sounds in a much different way than previously thought,” said Robert Dziak, an acoustics scientist with the National Oceanic and Atmospheric Administration and lead author on the study. “It was long thought that they generated their calls mostly by resonating sound in large chambers or cavities in their upper respiratory system.

“But this implies that the frequency of the whale’s calls are dictated by the size of the animal – the lower the frequency, the bigger the animal. We show that blue whales can make these low frequency sounds, and even change frequency in the middle of their call, by pulsing air through their vocal cords.”

“That also suggests that the change in the frequency might be cognitive. They are choosing to make it higher or lower in response to some sort of environmental stimulus.”

One theory is that as blue whale populations recover from commercial whaling, there are more of them and the lowering of frequency and other unusual characteristics of the calls are related to changes in population. It also is possible that an increase in ambient noise off the Pacific Coast plays a role, noted Joe Haxel, an Oregon State University acoustics specialist at Hatfield Marine Science Center.

“We conducted a year-long study of sound off the Oregon Coast and at times it can be really noisy out there,” Haxel said. “In addition to vibrant natural sounds – especially waves breaking on the beach – a few long-term studies have documented a substantial increase in ocean noise over several decades from expanding container shipping traffic.

“It may be possible the whales are modulating their vocalization frequency in response to an increase in human-generated noise. They are essentially trying to find a radio channel that has less static to communicate in.”

Dziak and his colleagues have created similar acoustic models to replicate the sounds of icebergs scraping across the seafloor as well as the explosions from undersea volcanic eruptions. To recreate the sound of a blue whale, they began using a clear call from a blue whale off Yaquina Head near Newport that they recorded using an undersea hydrophone that was part of a study to monitor the environmental impacts of wave energy.

They then developed acoustical models of the whale sound and incorporated anatomical respiratory system models of blue whales, the largest animals to have ever lived on Earth.

“We tried to envision a mechanism whereby whales could gradually lower the frequency of their calls through time, or produce calls with unusual harmonic structure, by only resonating sound in their upper respiratory chamber – and it was physically impossible,” said Dziak, who has a courtesy appointment in OSU’s College of Earth, Ocean, and Atmospheric Sciences.

“Only when we pulsed air through the process of opening and closing the vocal cords did we get a way to produce sounds that can change frequencies in mid-call as well as remove overtones. And this method produced models that matched the natural Yaquina Head blue whale call very, very closely.

“Lower-frequency sounds can be produced at lower intensity by the animal than high-frequency sounds and yet low-frequency sound still travels further,” Dziak pointed out. “Those factors may also play a role in the vocalization changes over the past two decades.”

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Bob Dziak, 541-867-0175, robert.p.dziak@noaa.gov;

Joe Haxel, 541-867-0282, joe.haxel@oregonstate.edu

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A blue whale off the California coast.

 

 

 

 

 

 

 


New algorithm, metrics improve autonomous underwater vehicles’ energy efficiency

CORVALLIS, Ore. – Robotics researchers have found a way for autonomous underwater vehicles to navigate strong currents with greater energy efficiency, which means the AUVs can gather data longer and better.

AUVs such as underwater gliders are valuable research tools limited primarily by their energy budget – every bit of battery power wasted via inefficient trajectories cuts into the time they can spend working.

“Historically, a lot of oceanography data sets and sampling came from using ships, which are expensive and can only really be out for a few days at a time,” said Dylan Jones, a third-year Ph.D. student in Oregon State University’s robotics program and lead author on the study. “With autonomous underwater vehicles, you can get months-long monitoring. And a way to extend those vehicles’ missions is through smarter planning for how they get from one point of interest to another.”

Jones and Ph.D. advisor Geoff Hollinger, assistant professor of mechanical engineering in OSU’s College of Engineering, have built a framework for the vehicles to plan energy-efficient trajectories through disturbances that are strong and uncertain, like ocean currents and wind fields.

The framework involves an algorithm that samples alternate paths, as well as comparison metrics that let a vehicle decide when it makes sense to switch paths based on new information collected about environmental disturbances.

The researchers tested the framework in a simulated environment – a data set of currents from the Regional Ocean Modeling System – and also on a windy lake with an autonomous boat.

The results, recently published in IEEE Robotics and Automation Letters, show that the algorithm can plan vehicle paths that are more energy efficient than ones planned by existing methods, and that it’s robust enough to deal with environments for which not much data is available.

Findings also indicate that three of the framework’s five path comparison metrics can be used to plan more efficient routes compared to planning based solely on the ocean current forecast.

“We generalized past trajectory optimization techniques and also removed the assumption that trajectory waypoints are equally spaced in time,” Jones said. “Removing that assumption improves on the state of the art in energy-efficient path planning. 

“These are under-actuated vehicles – they don’t go fast in relation to the strong ocean currents, so one way to get them to travel more efficiently is to go with the flow, to coast and not use energy,” he added. “We’re building more intelligence into these vehicles so they can more reliably accomplish their missions.”

Jones notes that overcoming strong disturbances is a critical component of putting any kind of robot in a real-life environment. Past planning algorithms haven’t always considered the dynamics of the vehicle they were planning for, he said.

“Sometimes we make assumptions in the lab or do simulations that don’t translate in the real world,” Jones said. “Sometimes a disturbance is too strong to be overcome, or sometimes it can be overcome but the path deviates so significantly that it would put the robot in a danger area. We have to consider all the possible locations of a robot. There are smarter ways of considering these various disturbances, and this gives us a better way of planning paths that are least affected by disturbances.”

Any disconnect between the controller and the planner can be dangerous, Jones said.

“The way we see this work going is to bridge that gap – how do we look at paths that are easier for controllers to follow, and how do we make controllers follow paths better?” he said. “We can be more energy efficient when we consider the whole environment, planning paths so that the controller of the vehicle doesn’t have to work as hard.”

Future research will also deal with “informative path planning” – planning paths that initially gather information about the environment and disturbances that the algorithm can use later to plan more energy-efficient routes.

“How do we combine these two ideas – planning a path for energy efficiency while also trying to gather information that will inform efficient path planning?” Jones said. “There will be tradeoffs and it might come down to, do I pay five hours now to save six hours later on? Another possible research direction is to look at a multivehicle situation where one vehicle can scout ahead and relay information to one or more others – they could possibly have a low shared energy cost by intelligently assigning goals and sharing information.”

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Steve Lundeberg, 541-737-4039

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AUV paths planned by framework

OSU inks largest research grant in its history to begin ship construction

CORVALLIS, Ore. – Oregon State University has just received a grant of $121.88 million from the National Science Foundation to spearhead the construction of a new class of research vessels for the United States Academic Research Fleet. It is the largest grant in the university’s history.

This grant will fund the construction of the first of three planned vessels approved by Congress for research in coastal regions of the continental United States and Alaska. When funding for the next two vessels is authorized, the total grant to OSU could increase to as much as $365 million. The first vessel is slated to be operated by OSU for research missions focusing on the U.S. West Coast. The NSF will begin the competitive selection of operating institutions for the second and third vessels later this year – likely to universities or consortia for operations on the U.S. East Coast and the Gulf of Mexico.

“Oregon State University is extremely proud to lead this effort to create the next generation of regional ocean-going research vessels funded by NSF,” said OSU President Edward J. Ray. “Our exceptional marine science programs are uniquely positioned to advance knowledge of the oceans and to seek solutions to the threats facing healthy coastal communities – and more broadly, global ecological well-being – through their teaching and research.”

OSU was selected by the National Science Foundation in 2013 to lead the initial design phase for the new vessels, and to develop and execute a competitive selection for a shipyard in the United States to do the construction. Gulf Island Shipyards, LLC, in Louisiana was chosen and will conduct the detailed design verification over the next year. Officials hope to have a keel-laying ceremony for the first vessel in the spring of 2018, with the ship delivered to OSU for a year of extensive testing in 2020.

This new class of modern well-equipped ships is essential to support research encompassing marine physical, chemical, biological and geologic processes in coastal waters, said Roberta Marinelli, dean of Oregon State’s College of Earth, Ocean, and Atmospheric Sciences.

“Rising sea levels, ocean acidification, low-oxygen waters or ‘hypoxia,’ declining fisheries, offshore energy, and the threat of catastrophic tsunamis are issues not only in the Pacific Northwest but around the world,” Marinelli said. “These new vessels will provide valuable scientific capacity for better understanding our changing oceans.”

The ships will be equipped to conduct detailed seafloor mapping, to reveal geologic structures important to understanding processes such as subduction zone earthquakes that may trigger tsunamis. The Pacific Northwest is considered a high-risk region because of the Cascadia Subduction Zone, which has produced about two dozen major earthquakes of magnitude 8.0 or greater over the past 10,000 years.

The new ships will also be equipped with advanced sensors that will be used to detect and characterize harmful algal blooms, changing ocean chemistry, and the interactions between the sea and atmosphere. The emerging fields of wave, tidal and wind energy will benefit from ship observations. Oregon State is the site of the Northwest National Marine Renewable Energy Center, which in December was awarded a grant of up to $35 million from the U.S. Department of Energy to create the world’s premier wave energy test facility in Newport.

Some characteristics of the new regional class research vessels (RCRVs), which were designed by The Glosten Associates, a naval architecture firm based in Seattle:

  • 193 feet long with a 41-foot beam;
  • Range of approximately 7,000 nautical miles;
  • Cruising speed is 11.5 knots with a maximum speed of 13 knots;
  • 16 berths for scientists and 13 for crew members;
  • Ability to stay out at sea for at least 21 days before returning to port;
  • High bandwidth satellite communications for streaming data and video to shore;

“This class of ships will enable researchers to work much more safely and efficiently at sea because of better handling and stability, more capacity for instrumentation and less noise,” said Clare Reimers, a professor in the College of Earth, Ocean, and Atmospheric Sciences and project co-leader. “The design also has numerous ‘green’ features, including an optimized hull form, waste heat recovery, LED lighting, and variable speed power generation.”

Oregon State is expected to begin operating the first of the new ships in the fall of 2021, after a year of testing and then official Academic-Fleet designation by the University-National Oceanographic Laboratory System (UNOLS), according to Demian Bailey, also a project co-leader for OSU.

“There will be a full year of testing because there are many interconnected systems to try out,” Bailey said. “Any new ship needs to have shakedown cruises, but we’ll have to test all of the scientific instrumentation as well, from the acoustic multibeam seafloor mapping system to its seawater and meteorological data collection, processing and transfer capabilities.

“These ships will be very forward-looking and are expected to support science operations for 40 years or longer. They will be the most advanced ships of their kind in the country.”

OSU previously operated the 184-foot R/V Wecoma from 1975 until 2012, when it was retired. The university then assumed operations of Wecoma’s sister ship, R/V Oceanus, from Woods Hole Oceanographic Institution; that ship will be retired when the new ship is ready.

The tentative timetable for the new ships:

  • Ship No. 1 keel laying – spring 2018;
  • Ship No. 1 transition to OSU for a year of testing – fall 2020;
  • Ship No. 1 should be fully tested, have UNOLS designation and be fully operational by fall 2021;
  • Ship No. 2 – Keel laying in winter of 2018, delivery in spring 2021, and UNOLS designation in late spring 2022;
  • Ship No. 3 – Keel laying in fall 2020, delivery in spring 2022, and UNOLS designation in spring 2023.

More information on the ships and the project is available at: http://ceoas.oregonstate.edu/ships/rcrv/.

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Mark Floyd, 541-737-0788

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Regional class research vessel

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Krill hotspot fuels incredible biodiversity in Antarctic region

CORVALLIS, Ore. – There are so many Antarctic krill in the Southern Ocean that the combined mass of these tiny aquatic organisms is more than that of the world’s 7.5 billion human inhabitants.

Scientists have long known about this important zooplankton species, but they haven’t been certain why particular regions or “hotspots” in the Southern Ocean are so productive. One such hotspot exists off Anvers Island – along the western Antarctic Peninsula – where high densities of Antarctic krill episodically concentrate near the shore close to a number of Adélie penguin breeding colonies. 

As it turns out, a perfect combination of tides and wind is responsible, according to scientists who just published a study on the krill in the journal Deep Sea Research. The research was funded by the National Science Foundation.

“This region off the western Antarctic Peninsula has been a known breeding area for Adélie penguins for thousands of years,” said Kim Bernard, a biological oceanographer at Oregon State University and lead author on the study. “We know it today as a krill hotspot and it probably has been for some time.

“But despite their abundance, there is growing concern about krill not only because of climate change, but because they are now being harvested for human food, nutritional supplements and aquaculture feed. Yet historically we’ve known little about what makes this particular area so productive for krill. So we set out to learn more about it.”

Bernard and a team of colleagues spent four consecutive summer seasons in the Antarctic mapping the patterns in distribution and biomass of Antarctic krill, also known as Euphausia superba. They also sought to identify the environmental conditions responsible for the hotspot. 

What they discovered is a near-perfect system in which krill aggregations situated over the Palm Deep Canyon – a region of nutrient-rich waters that produce a lot of food for the krill – are delivered close to shore by tidal currents and winds. When the winds are westerly and the tides are diurnal – one high tide and one low tide each day – the krill biomass close to shore is at its peak and krill aggregations are huge.

“It’s neat – we can predict exactly when humpback whales will be close to shore off Palmer Station just based on the tides,” Bernard said. “When there are diurnal tides, you’ll see krill from the surface to the ocean floor – they are everywhere. And when they are, the whales are there, too.

“This concentration and transport toward shore are particularly important for the penguins that breed there. The farther they have to go to forage, the less their chicks have to eat and chick weight is a huge factor in their survival. A difference of a few hundred grams in chick weight is the difference between life and death.”

When the tides shift to semi-diurnal – two high and two low tides daily – currents move the krill away from shore and their predators follow. Likewise, a shift to southerly winds keeps the krill farther from shore and more spread out.

Antarctic krill can live five to seven years, and grow to a length of a little more than two inches. They don’t reach sexual maturity for two years, and when they reproduce, they must release their eggs in water roughly 1,000 meters (or about 3,200 feet) deep. That’s because they need a certain period of time to develop as they drift to the ocean floor, and another period of time to go through different life stages as they re-ascend to the surface.

Studies have shown that sea ice may be critical to their survival, but scientists are not exactly sure why, Bernard said.

“We see very strong correlations between krill biomass and sea ice,” she noted. “When the sea ice is low, the krill populations crash the next summer. It could be a change in algae or other food for them, or it could be that sea ice provides shelter from predators, or affects the currents in some way. We just don’t yet know.

“It would be nice to find out, because sea ice abundance may vary greatly in the future.”

Bernard is on the faculty of OSU’s College of Earth, Ocean, and Atmospheric Sciences.

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Mark Floyd, 541-737-0788

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Penguins rely on close-to-shore krill

Public meeting set Thursday on Marine Studies Building at Hatfield Center

NEWPORT, Ore. – Oregon State University will host an informational public meeting this Thursday, June 15, to update local residents on plans for a new Marine Studies Building at OSU’s Hatfield Marine Science Center in Newport.

The meeting will run from 5 to 6:30 p.m. in Hatfield’s Visitor Center. A 45-minute presentation and question-and-answer session will be followed by a reception and displays. The Hatfield Center is located at 2030 S.E. Marine Science Drive in Newport, just southeast of the Highway 101 bridge.

The presentation will also be streamed live over Adobe Connect at http://oregonstate.adobeconnect.com/hmsc-fw407/

Oregon State University has launched a Marine Studies Initiative – a new research and teaching model to help sustain healthy oceans and ensure wellness, environmental health and economic prosperity for coastal communities.

“A component of the Marine Studies Initiative includes the construction of a research and teaching facility – the Marine Studies Building on the HMSC campus – and student housing at another location in Newport,” said Steve Clark, vice president for university relations and marketing.

“This public meeting in Newport is an opportunity to hear how the university will ensure that the design, engineering and construction of the Marine Studies Building and student housing meet or exceed the earthquake and tsunami performance and safety commitments that OSU President Ed Ray has made.”

Presentations will be made by­­­­­­­­­­­­­­­­­­­­­­­­­­­ Bob Cowen, director of OSU’s Hatfield Marine Science Center, and Tom Robbins, project manager and architect with Yost Grube Hall Architecture.

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Steve Clark, 541-737-3808, steve.clark@oregonstate.edu; Bob Cowen, 541-867-0211, Robert.Cowen@oregonstate.edu