OREGON STATE UNIVERSITY

marine science and the coast

New Studies Highlight Concern over Rising Jellyfish Populations

CORVALLIS, Ore. – Jellyfish populations appear to be increasing along the West Coast and in the Bering Sea and scientists studying the phenomenon are concerned because jellyfish may feed on the same plankton species targeted by herring, sardines and anchovies, juveniles salmon and other fishes.

Compounding the situation, the scientists say, is that there are few predators for adult jellyfish.

“A few birds and fish will eat the jellies in their larval or juvenile stages,” said Richard D. Brodeur, a NOAA biologist and adjunct professor in the College of Oceanic and Atmospheric Sciences at Oregon State University. “But once the medusae reach a certain size, not much eats them.”

Newly published studies by Brodeur, OSU oceanographer Lorenzo Ciannelli and others are looking at the link between climate change and jellyfish populations and they have found this relationship is complex. The prevailing school of thought has been that as ocean waters warm, jellyfish populations will increase. But they have discovered that food sources, reproduction dynamics and ocean currents all play a role in jellyfish populations.

In a paper just published in Progress in Oceanography, the scientists describe a steep increase in jellyfish populations in the Bering Sea through the 1990s, peaking in the summer of 2000. But during the years of 2001 through 2005, when scientists recorded some of the warmest temperatures ever in the Bering Sea, jellyfish populations declined.

“They were still well ahead of their historic averages for that region,” said Ciannelli, an assistant professor in OSU’s College of Oceanic and Atmospheric Sciences. “But clearly jellyfish populations are not merely a function of water temperature.”

One key to learning more about jellyfish expansion has been Ciannelli’s work looking into the organisms’ complex life cycle. Adult males release their sperm into the water column and fertilize the eggs that female adults have released. From each fertilized egg, a larva is produced that attaches itself to a rock or some other solid surface and produces a polyp. These polyps reproduce asexually and eventually the young medusae detach themselves and begin the life cycle anew.

The researchers’ preliminary findings suggest that warmer ocean waters may enhance the stage where polyps transform into colonies, but that hypothesis is based on lab work, not field research. The reason, Ciannelli says, is that polyps are notoriously difficult to locate because of their small size.

“We think that higher temperatures lead to a higher metabolic rate and faster division of cells,” he said. “It accelerates the whole system. But finding polyps in the Bering Sea is like trying to do research on the dark side of the moon.”

Ciannelli and his colleagues are funded by the National Science Foundation to better understand how these polyps are distributed. One hypothesis is that there is a single unique source that produces the small jellyfish in the Bering Sea and their expansion is a product of currents. An alternative theory is that the jellyfish are using pockets of warm water to establish new colonies, which would be consistent with global warming scenarios, he said.

“What we’re trying to figure out is where the energy of the food web is going,” Ciannelli pointed out. “If it is going to the jellyfish, which are eating the plankton, it creates an overall sink because they have few predators. It is diverting the energy of the ocean from the pelagic to the benthic system.”

Scientists have begun looking more closely at food sources for jellyfish off the West Coast of the United States and their findings are surprising. In a paper published in the April 2008 issue of the Marine Ecology Progress Series, a team of scientists including Brodeur quantified diet and predation rates for large jellyfish from an upwelling region in the northern California Current. They found that in an area north of Cape Blanco, Ore., abundant populations of jellyfish ate an average of one-third of all the euphausiid – a type of zooplankton – eggs available each day. Consumption of other taxa reached 10 to 12 percent of the standing stocks.

On the other hand, copepods, important components of the marine food web, were consumed at relatively low levels – less than 1 percent a day. Lead author on that study was Cynthia L. Suchman, who conducted her research out of OSU’s Hatfield Marine Science Center Hatfield Marine Science Center in Newport, Ore., where Brodeur works.

Few scientists are conducting long-term jellyfish studies and the authors suggest that zooplankton studies and predation impacts by jellyfish should be incorporated into long-term studies and ecosystem models. “Unfortunately,” Brodeur said, “there hasn’t been a great deal of funding for jellyfish studies, so we don’t know as much as we should about their impact.”

Trawl surveys by Brodeur and his colleagues found that the spatial overlap between jellyfish and most pelagic fishes, including salmon, was relatively small. But in a forthcoming article in Marine Biology, the researchers point out that the overlap with “planktivorous” fishes that consume copepods and euphausiid eggs – including Pacific sardines, the northern anchovy, Pacific saury, and Pacific herring – was considerable. These prey species also are critical to the diets of salmon and other species in the ocean.

“We’ve been collecting data now for about nine years and it appears, at least on a preliminary basis, that when cold water regimes are prevalent, jellyfish numbers increase,” Brodeur said. “During the warmer years, when food sources are scarcer, there may be fewer jellyfish, but they grow quickly – whether because of elevated metabolic rates or less competition, we don’t know.”

This summer Brodeur will be involved in a series of cruises off the Oregon coast to sample jellyfish populations and see what effect this year’s cold-water La Niña phenomenon may have had.

“It won’t be a good sign for the ecosystem if we get a lot of jellies out there,” he said.

Their research has been supported by the National Science Foundation, NOAA and the National Marine Fisheries Service.

 

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Ric Brodeur,
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Chrysaora melanaster

Crabbers collaborate with OSU researchers to monitor ocean temperature, hypoxia

CORVALLIS, Ore. – In a unique, symbiotic relationship, Oregon crabbers are working with Oregon State University researchers funded by Oregon Sea Grant to use their crab pots as underwater monitoring stations where data collectors attached to the pots gather vital oceanographic information.

This information might help crabbers more effectively locate their catch while helping scientists provide answers to challenging research questions, such as why and when hypoxia zones form in coastal waters.

Historically, some fishers say they have been wary of researchers for fear that the data gathered would be used to close fisheries or restrict catches and seasons. Likewise, some scientists have been skeptical of the quality of data collected using research technologies in the hands of fishers.

But this project, and other shared research efforts at OSU, demonstrates that fisher-researcher collaboration can work very well, collecting robust data, reducing research costs and helping better understand Oregon’s most valuable fishery: Dungeness crab.

“It’s taken some time to develop trust on both sides, but we’ve figured out that engaging the fishermen actually improves the data,” said Michael Harte, a professor in the OSU College of Oceanic and Atmospheric Sciences and director of the Marine Resource Management Program. “This is fantastic for us. It would cost many thousands of dollars to deploy a single scientific buoy, but by working with the crab fishermen, we can deploy fixed buoys for about $100 each (the cost of the device).”

Because crab pots are positioned using GPS and distributed throughout much of Oregon’s coastal ocean, data can be gathered from a much broader geographical range than using high tech ocean observing methods, such as buoys, towed platforms, or autonomous underwater gliders, which are expensive to purchase and operate.

The temperature data collectors attached to the crab pots are each about the size of a quarter and record temperature data every 10 minutes during the nine-month crabbing season. The information is then scanned and uploaded to computers for analysis and evaluation by project participants.

The OSU researchers, led by oceanographer Kipp Shearman, are working with 10 Oregon crabbers, attaching sensors to about 60 crab pots deployed between Port Orford in the south to Astoria in the north. Most commercial crabbers use between 300 and 800 pots, so the OSU scientists are able to select the locations where they want their sensors deployed.

“One real benefit is that by using the crab pots, we’re increasing both the temporal and spatial resolution of the data,” said Jeremy Childress, an OSU graduate student in Marine Resource Management who is working with Shearman and Harte. “We’re also utilizing the local knowledge of fishers to help direct our research, which is very helpful.”

Al Pazar, a crab fisherman who lives in Florence and fishes out of Newport, said helping OSU researchers collect data is his way of giving back to an industry that’s provided him with a solid livelihood for many years.

“Fishing’s been very good to me, and I’m happy to give something back,” Pazar said. “I love working with OSU, and Sea Grant in particular has helped establish a good connection between Oregon’s fishing industry and academia. The data gathering we do might help answer some important questions. It’s a no-brainer to utilize the local volunteers from the fishing fleets and their gear.”

Childress said that bringing people together who’ve traditionally not worked together is “the really the exciting part.” He credits former OSU graduate student Susan Holmes, who expanded statewide the project started by Shearman off Newport with seed funding from Oregon Sea Grant.

Because of the success of the temperature sensors, Childress and Shearman have developed a larger device that can record both temperature and dissolved oxygen levels in the water near the crab pots. This information could help scientists better understand and predict hypoxia, a lack of oxygen in the water that causes massive die-offs of organisms, including crab, in areas sometimes called “dead zones.”

Although off-the-shelf oxygen sensors are available, Childress is able to build a custom made sensor for about one-third the cost of the others.

“No oxygen means dead crabs or no crab, so the crab fishermen are happy to work with us,” Harte said. “They and their crab pots are going to be out there anyway, and we don’t need huge research grants to tap into this ready-made ocean observing system.”

Harte said he and his colleagues are fortunate to have had Oregon Sea Grant funding the project for two years.

“Sea Grant has been visionary enough to realize this is a great way to engage fishermen in science,” Harte said. “So we’re learning that scientists and fishermen, working together, can collect valid scientific data in a robust way using a relatively inexpensive system that improves our understanding of the ocean. Everybody wins.”

 

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Kipp Shearman, 541-737-1866

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Crab Pot Sensor

HMSC to Host Forum this September on Offshore Aquaculture in the Pacific Northwest

CORVALLIS, Ore. – Oregon State University’s Hatfield Marine Science Center will host a two-day forum in September that will explore the potential challenges and opportunities of developing offshore aquaculture programs in the Pacific Northwest.

Sponsored by numerous federal and state agencies, as well as private foundations, the forum, “Offshore Aquaculture in the Pacific Northwest,” is limited to 125 participants. Information about the program is available online at http://oregonstate.edu/conferences/aquaculture2008/. Open registration begins on July 15.

Chris Langdon, an OSU professor who directs the Molluscan Broodstock Program at the Hatfield Marine Science Center, is coordinating the forum. He says the event is designed to be informational and will explore the potential downsides as well as the rewards of offshore aquaculture in the Northwest region.

“Global population is estimated to increase by another 50 percent in the next 30-40 years and commercial fish stocks around the world are at or above sustainable harvest levels,” Langdon said. “We need to be exploring other avenues of seafood production.

“Any expansion of offshore aquaculture in the United States would require a strong regulatory framework with environmental safeguards to protect natural resources and ensure consumer safety,” he added.

The Pacific Northwest has comparatively clean ocean waters that could allow for production of high-value, cold-water fish and shellfish species.

Speakers at the forum include legislators, community leaders, aquaculture industry representatives, fishing industry representatives, economists and scientists. Among the topics: potential business models for aquaculture, fish and shellfish species suitable for the Pacific Northwest, environmental issues, biological and management issues, and siting and engineering challenges.

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Chris Langdon,
541-867-0231

Lionfish Decimating Other Tropical Fish Populations, Threaten Coral Reefs

CORVALLIS, Ore. – The invasion of predatory lionfish in the Caribbean region poses yet another major threat there to coral reef ecosystems – a new study has found that within a short period after the entry of lionfish into an area, the survival of other reef fishes is slashed by about 80 percent.

Aside from the rapid and immediate mortality of marine life, the loss of herbivorous fish also sets the stage for seaweeds to potentially overwhelm the coral reefs and disrupt the delicate ecological balance in which they exist, according to scientists from Oregon State University.

Following on the heels of overfishing, sediment depositions, nitrate pollution in some areas, coral bleaching caused by global warming, and increasing ocean acidity caused by carbon emissions, the lionfish invasion is a serious concern, said Mark Hixon, an OSU professor of zoology and expert on coral reef ecology.

The study is the first to quantify the severity of the crisis posed by this invasive species, which is native to the tropical Pacific and Indian Ocean and has few natural enemies to help control it in the Atlantic Ocean. It is believed that the first lionfish – a beautiful fish with dramatic coloring and large, spiny fins – were introduced into marine waters off Florida in the early 1990s from local aquariums or fish hobbyists. They have since spread across much of the Caribbean Sea and north along the United States coast as far as Rhode Island.

“This is a new and voracious predator on these coral reefs and it’s undergoing a population explosion,” Hixon said. “The threats to coral reefs all over the world were already extreme, and they now have to deal with this alien predator in the Atlantic. These fish eat many other species and they seem to eat constantly.”

Findings of the new research will be published soon in Marine Ecology Progress Series. The lead author is Mark Albins, a doctoral student working with Hixon.

In studies on controlled plots, the OSU scientists determined that lionfish reduced young juvenile fish populations by 79 percent in only a five-week period. Many species were affected, including cardinalfish, parrotfish, damselfish and others. One large lionfish was observed consuming 20 small fish in a 30-minute period.

Lionfish are carnivores that can eat other fish up to two-thirds their own length, while they are protected from other predators by long, poisonous spines. In the Pacific Ocean, Hixon said, other fish have learned to avoid them and they also have more natural predators, particularly large groupers. In the Atlantic Ocean, native fish have never seen them before and have no recognition of danger. There, about the only thing that will eat lionfish is another lionfish – they are not only aggressive carnivores, but also cannibals.

“In the Caribbean, few local predators eat lionfish, so there appears to be no natural controls on them,” Hixon said. “And we’ve observed that they feed in a way that no Atlantic Ocean fish has ever encountered. Native fish literally don’t know what hit them.”

When attacking another fish, Hixon said, the lionfish will use its large, fan-like fins to herd smaller fish into a corner and then swallow them in a rapid strike. Because of their natural defense mechanisms they are afraid of almost no other marine life. And the poison released by their sharp spines can cause extremely painful stings to humans – even leading to fatalities for some people with heart problems or allergic reactions.

“These are pretty scary fish, and they aren’t timid,” Hixon said. “They will swim right up to a diver in their feeding posture, looking like they’re ready to eat. That can be a little spooky.”

Their rapid reproduction potential, Hixon said, must now be understood in context with their ability to seriously depopulate coral reef ecosystems of other fish. Parrotfishes and other herbivores prevent seaweeds from smothering corals. A major, invasive predator such as lionfish could disrupt the entire system.

Options to manage the lionfish threat are limited, Hixon said. They can be collected individually, which may be of localized value, but that approach offers no broad solution. Recovery or introduction of effective predators might help. Groupers, a fish that has been known to eat lionfish in the Pacific Ocean, have been heavily over-fished in the tropical Atlantic Ocean, Hixon said.

“We have to figure out something to do about this invasion before it causes a major crisis,” Hixon said. “We basically had to abandon some studies we had under way in the Atlantic on population dynamics of coral reef fish, because the lionfish had moved in and were eating everything.”

OSU scientists say they hope to continue research on lionfish in their native Pacific Ocean habitats for information that may be of use in their control.

 

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Mark Hixon,
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Mark Albins

OSU researcher Mark Albins studying lionfish underwater

New Study: Hatchery fish may hurt efforts to sustain wild salmon runs

CORVALLIS, Ore. – Steelhead trout that are originally bred in hatcheries are so genetically impaired that, even if they survive and reproduce in the wild, their offspring will also be significantly less successful at reproducing, according to a new study published today by researchers from Oregon State University.

The poor reproductive fitness – the ability to survive and reproduce – of the wild-born offspring of hatchery fish means that adding hatchery fish to wild populations may ultimately be hurting efforts to sustain those wild runs, scientists said.

The study found that a fish born in the wild as the offspring of two hatchery-reared steelhead averaged only 37 percent the reproductive fitness of a fish with two wild parents, and 87 percent the fitness if one parent was wild and one was from a hatchery. Most importantly, these differences were still detectable after a full generation of natural selection in the wild.

The effect of hatcheries on reproductive fitness in succeeding generations had been predicted in theory, experts say, but until now had never been demonstrated in actual field experiments.

“If anyone ever had any doubts about the genetic differences between hatchery and wild fish, the data are now pretty clear,” said Michael Blouin, an OSU professor of zoology. “The effect is so strong that it carries over into the first wild-born generation. Even if fish are born in the wild and survive to reproduce, those adults that had hatchery parents still produce substantially fewer surviving offspring than those with wild parents. That’s pretty remarkable.”

An earlier report, published in 2007 in the journal Science, had already shown that hatchery fish that migrate to the ocean and return to spawn leave far fewer offspring than their wild relatives. The newest findings suggest the problem does not end there, but carries over into their wild-born descendants.

The implication, Blouin said, is that hatchery salmonids – many of which do survive to reproduce in the wild– could be gradually reducing the fitness of the wild populations with which they interbreed. Those hatchery fish provide one more hurdle to overcome in the goal of sustaining wild runs, along with problems caused by dams, loss or degradation of habitat, pollution, overfishing and other causes.

Aside from weakening the wild gene pool, the release of captive-bred fish also raises the risk of introducing diseases and increasing competition for limited resources, the report noted.

This research, which was just published in Biology Letters, was supported by grants from the Bonneville Power Administration and the Oregon Department of Fish and Wildlife. It was based on years of genetic analysis of thousands of steelhead trout in Oregon’s Hood River, in field work dating back to 1991. Scientists have been able to genetically “fingerprint” three generations of returning fish to determine who their parents were, and whether or not they were wild or hatchery fish.

The underlying problem, experts say, is Darwinian natural selection.

Fish that do well in the safe, quiet world of the hatcheries are selected to be different than those that do well in a much more hostile and predatory real-world environment. Using wild fish as brood stock each year should lessen the problem, but it was just that type of hatchery fish that were used in the Hood River study. This demonstrates that even a single generation of hatchery culture can still have strong effects.

Although this study was done with steelhead trout, it would be reasonable to extrapolate its results to other salmonids, researchers said. It’s less clear what the findings mean to the many other species that are now being bred in captivity in efforts to help wild populations recover, Blouin said, but it’s possible that similar effects could be found.

Captive breeding is now a cornerstone of recovery efforts by conservation programs for many threatened or endangered species, the researchers noted in their report. Thousands of species may require captive breeding to prevent their extinction in the next 200 years – which makes it particularly important to find out if such programs will ultimately work. This study raises doubts.

“The message should be clear,” the researchers wrote in their report’s conclusion. “Captive breeding for reintroduction or supplementation can have a serious, long-term downside in some taxa, and so should not be considered as a panacea for the recovery of all endangered populations.”

 

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Michael Blouin, 541-737-2362

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Returning Chinook salmon

Oregon group planning nation’s first tsunami evacuation structure

CANNON BEACH, Ore. – A group of university experts, state and federal officials, and local residents in the coastal town of Cannon Beach, Ore., are working together to create a new city hall – but more importantly, the first structure in the United States ever built specifically to survive the force of a tsunami.

A report on the issue has been completed, research programs at Oregon State University will do further studies this summer, and a conference is planned for this fall. The project goes to the heart of an issue of increasing urgency in the Pacific Northwest – what do you do when a major earthquake hits and a tsunami is imminent, but in the few minutes available there may not be time to run to high ground?

“We’ve already done a lot with public education to alert people in high risk zones about major earthquakes and tsunamis, and what to do,” said Harry Yeh, the Edwards Professor of Coastal and Ocean Engineering at OSU. “Those efforts are important and we’ll continue them. But at some point, knowing what to do may not be good enough if you don’t have the time to do it.”

The Cascadia Subduction Zone off the coast of Oregon, Washington and northern California causes enormous earthquakes that – depending on location – occur about every 220 to 525 years, along with associated tsunamis. Researchers believe the last such event occurred in 1700, causing a tsunami of such magnitude that it hit not only local shores but swept across the Pacific Ocean to Japan.

An updated study by the Oregon Department of Geology and Mineral Industries (DOGAMI) recently doubled the area in Cannon Beach that might be inundated by a tsunami, including almost all the commercial areas in this small city which has about 1,700 residents – not including the thousands of tourists that might be present on some days.

A subduction zone earthquake could be followed by a major tsunami 10-20 minutes later, experts say, while people are surrounded by collapsed buildings, blocked roads, traffic jams and possibly failed bridges. In the few minutes available – at this and many other coastal locations – the concept of “vertical evacuation” to the roof of a tall structure that would withstand the coming tsunami might offer the only realistic chance of survival for some people.

“Strong, reinforced concrete buildings can often survive a tsunami, we saw that in Indonesia in 2004,” Yeh said. “That event was very geologically similar to what we expect in the future of the Pacific Northwest, and it taught us a lot of lessons. Unfortunately, in East Asia those lessons came at a cost of 230,000 lives.”

OSU researchers, through their expertise with structural engineering, modeling and the world’s most sophisticated Tsunami Wave Basin, hope to help prevent a repetition of the Indonesian disaster for the people of Cannon Beach and many other coastal cities. They will work closely with officials at DOGAMI and others who are leading this broad state and community effort.

We know we can build a structure, usually with an open first story that could be used for parking or other community events, that will survive an earthquake and tsunami,” Yeh said. “Everyone agrees it would be good to have, but it will cost more. A realistic engineering and research goal is to find ways to bring those costs down as much as we possibly can, through our improved understanding of tsunami run-up forces. And we must ensure the building is strong enough to do its job – which is saving lives.”

If the project in Cannon Beach actually comes to fruition and the structure is built, Yeh said, it could form a model for other similar structures in many vulnerable coastal areas of the United States and around the world.

Jay Raskin, an architect, local resident and community leader in Cannon Beach, has led efforts there to embrace this project.

“Ever since the research made clear the risks we face in Cannon Beach from earthquakes and tsunamis, we’ve been interested in trying to do something to address this problem,” Raskin said. “We need a new city hall here, and we need to protect our community. A structure like this could help protect people’s lives in the event of a tsunami and give us a starting point around which to maintain government services and rebuild.”

Raskin said a design team that he helped organize will involve university, state, federal and private industry experts. Work will also be done to engage more community residents in the discussion, even though the city has been a coastal leader in tsunami education and preparation since the 1990s.

“There is general public support for creating a new city hall that is also a tsunami refuge,” Raskin said. “But there are also a lot of questions about how such a building would work both day-to-day and in an emergency, and how much it would cost. We need to be able to answer these questions so the public can weigh the benefits and risks to make an informed decision.”

Tsunami-resistant architecture, experts say, could be incorporated into a range of public structures such as city halls, convention centers, schools, or libraries, and conceptually even private buildings that meet the requirements. In Cannon Beach, a building is envisioned that would provide elevated refuge for 800 to 1,000 people.

To serve their purpose, these types of buildings would have to be able to withstand a major earthquake, have deep foundations, be at least two stories high, usually incorporate barrier walls to help dissipate wave forces, have a roof available for emergency evacuation, and meet other requirements. They would be of special value in any coastal community with a high level of visitors, many elderly residents or children, or where higher ground is a sufficient distance away that it may not be practical to reach it in the time available.

In Oregon, about 100,000 residents are in the tsunami inundation hazard zone every day, officials say, some with long travel distances to higher land.

A two-day workshop bringing together a range of university, community, state, federal and private experts will be held on Sept. 28-29 to further explore the Cannon Beach plans, with a field trip to the coast and a meeting in Portland.

 

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Harry Yeh, 541-737-8057

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Cannon Beach City Hall

An architect’s rendering of the possible structure.

Biological studies shed light on collapse of coral reefs

CORVALLIS, Ore. – An explosion of knowledge has been made in the last few years about the basic biology of corals, researchers say in a new report, helping to explain why coral reefs around the world are collapsing and what it will take for them to survive a gauntlet of climate change and ocean acidification.

Corals, it appears, have a genetic complexity that rivals that of humans. They have sophisticated systems of biological communication that are being stressed by global change, and are only able to survive based on proper function of an intricate symbiotic relationship with algae that live within their bodies.

After being a highly successful life form for 250 million years, disruptions in these biological and communication systems are the underlying cause of the coral bleaching and collapse of coral reef ecosystems around the world, scientists will report tomorrow in the journal Science.

The research was funded in part by the National Science Foundation.

“We’ve known for some time the general functioning of corals and the problems they are facing from climate change,” said Virginia Weis, a professor of zoology at Oregon State University. “But until just recently, much less has been known about their fundamental biology, genome structure and internal communication. Only when we really understand how their physiology works will we know if they can adapt to climate changes, or ways that we might help.”

Corals are tiny animals, polyps that exist as genetically identical individuals, and can eat, defend themselves and kill plankton for food. In the process they also secrete calcium carbonate that becomes the basis for an external skeleton on which they sit. These calcified deposits can grow to enormous sizes over long periods of time and form coral reefs – one of the world’s most productive ecosystems, which can harbor more than 4,000 species of fish and many other marine life forms.

But corals are not really self sufficient. Within their bodies they harbor highly productive algae – a form of marine plant life – that can “fix” carbon, use the energy of the sun to conduct photosynthesis and produce sugars.

 “Some of these algae that live within corals are amazingly productive, and in some cases give 95 percent of the sugars they produce to the coral to use for energy,” Weis said. “In return the algae gain nitrogen, a limiting nutrient in the ocean, by feeding off the waste from the coral. It’s a finely developed symbiotic relationship.”

What scientists are learning, however, is that this relationship is also based on a delicate communication process from the algae to the coral, telling it that the algae belong there, and that everything is fine. Otherwise the corals would treat the algae as a parasite or invader and attempt to kill it.

“Even though the coral depends on the algae for much of its food, it may be largely unaware of its presence,” Weis said. “We now believe that this is what’s happening when the water warms or something else stresses the coral – the communication from the algae to the coral breaks down, the all-is-well message doesn’t get through.

“The algae essentially comes out of hiding and faces an immune response from the coral.”

This internal communication process, Weis said, is not unlike some of the biological processes found in humans and other animals. One of the revelations in recent research, she said, is the enormous complexity of coral biology, and even its similarity to other life forms. A gene that controls skeletal development in humans, for instance, is the identical gene in corals that helps it develop its external skeleton – conserved in the different species over hundreds of millions of years since they parted from a common ancestor on their separate evolutionary paths.

There’s still much to learn about this process, researchers said, and tremendous variation in it. For one thing, there are 1,000 species of coral and perhaps thousands of species of algae all mixing and matching in this symbiotic dance. And that variation, experts say, provides at least some hope that combinations will be found which can better adapt to changing conditions of ocean temperature, acidity or other threats.

The problems facing coral reefs are still huge, and increasing. They are being pressured by changes in ocean temperature, pollution, overfishing, sedimentation, acidification, oxidative stress and disease, and the synergistic effect of some of these problems may destroy reefs even when one cause by itself would not. Some estimates have suggested 20 percent of the world’s coral reefs are already dead and an additional 24 percent are gravely threatened.

The predicted acidification of the oceans in the next century is expected to decrease coral calcification rates by 50 percent and promote the dissolving of coral skeletons, the researchers noted in their report.

“With some of the new findings about coral symbiosis and calcification, and how it works, coral biologists are now starting to think more outside the box,” Weis said. “Maybe there’s something we could do to help identify and protect coral species that can survive in different conditions. Perhaps we won’t have to just stand by as the coral reefs of the world die and disappear.”

 

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Virginia Weis, 541-737-4359

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Coral Colony

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Coral Skeleton

OSU scientists identify endangered right whales where they were presumed extinct

NEWPORT, Ore. – Using a system of underwater hydrophones that can record sounds from hundreds of miles away, a team of scientists from Oregon State University and the National Oceanic and Atmospheric Administration has documented the presence of endangered North Atlantic right whales in an area they were thought to be extinct.

The discovery is particularly important, researchers say, because it is in an area that may be opened to shipping if the melting of polar ice continues, as expected.

Results of the study were presented this week at a meeting of the Acoustical Society of America in Portland, Ore.

The scientists are unsure of exactly how many whales were in the region, which is off the southern tip of Greenland and site of an important 19th-century whaling area called Cape Farewell Ground. But they recorded more than 2,000 right whale vocalizations in the region from July through December of 2007.

“The technology has enabled us to identify an important unstudied habitat for endangered right whales and raises the possibility that – contrary to general belief – a remnant of a central or eastern Atlantic stock of right whales still exists and might be viable,” said David Mellinger, an assistant professor at OSU’s Hatfield Marine Science Center in Newport and chief scientist of the project.

“We don’t know how many right whales there were in the area,” Mellinger added. “They aren’t individually distinctive in their vocalizations. But we did hear right whales at three widely space sites on the same day, so the absolute minimum is three. Even that number is significant because the entire population is estimated to be only 300 to 400 whales.”

Only two right whales have been sighted in the last 50 years at Cape Farewell Ground, where they had been hunted to near extinction prior to the adoption of protective measures.

Funded by NOAA’s Office of Ocean Exploration and Research, the project began in 2007 with the deployment of five hydrophones off the coast of Greenland. These instruments, built by Haru Matsumoto at OSU, were configured to continuously record ambient sounds below 1,000 Hz – a range that includes calls of the right whale – over a large region of the North Atlantic.

Right whales produce a variety of sounds, Mellinger said, and through careful analysis these sounds can be distinguished from other whales. The scientists used recordings of North Atlantic and North Pacific right whales to identify the species’ distinct sounds, including vocalizations known as “up” calls. Beginning in July of 2007, the scientists recorded a total of 2,012 calls in the North Atlantic off Greenland.

The pattern of recorded calls suggests that the whales moved from the southwest portion of the region in a northeasterly direction in late July, and then returned in September – putting them directly where proposed future shipping lanes would be likely.

“Newly available shipping lanes through the Northwest Passage would greatly shorten the trip between Europe and East Asia, but would likely cross the migratory route of any right whales that occupy the region,” said Phillip Clapham, a right whale expert with NOAA’s National Marine Mammal Laboratory, who participated in the study. “It’s vital that we know about right whales in this area in order to effectively avoid ship strikes on what could be a quite fragile population.”

In addition to Mellinger and Clapham, scientists involved in the project include Sharon Nieukirk, Karolin Klinck, Holger Klinck and Bob Dziak of the Cooperative Institute for Marine Resources Studies – a joint venture between OSU and NOAA; and Bryndís Brandsdóttir, of the University of Iceland.

This is the third time that Mellinger’s team has used hydrophones to locate endangered right whales. In the January 2004 issue of the journal Marine Mammal Science, Mellinger and his colleagues outlined how they used autonomous hydrophones to identify right whales in the Gulf of Alaska, where only one confirmed sighting had taken place in 26 years. And they identified the seasonal occurrence of right whales off Nova Scotia in a 2007 issue of the journal.

OSU scientists first began hearing whale sounds several years ago on a U.S. Navy hydrophone network. The hydrophone system – called the Sound Surveillance System, or SOSUS – was used by the Navy during the Cold War to monitor submarine activity in the northern Pacific Ocean. As the Cold War ebbed, these and other military assets were offered to civilian researchers performing environmental studies.

An Oregon State researcher, Christopher Fox, first received permission from the Navy to use the hydrophones at his laboratory at OSU's Hatfield Marine Science Center to listen for undersea earthquakes – a program now directed by Bob Dziak.

While listening for earthquakes, the OSU researchers begin picking up sounds of ships, marine landslides – and whales. Matsumoto, an engineer at the center, then developed autonomous hydrophones that can be deployed independently. Hydrophones since have become an important tool for marine ecologists, as well as geologists.

Media Contact: 
Source: 

David Mellinger, 541-867-0372

Multimedia Downloads
Multimedia: 

Hydrophone

Scientists including Matt Fowler, who works for both Oregon State University and NOAA, deploy a hydrophone in the North Atlantic aboard the Icelandic Coast Guard
cutter Aegir that will record sounds emitted by endangered whales and other species. (photo courtesy of Dave Mellinger, Oregon State
University)

Oregon Sea Grant publication explores offshore aquaculture

CORVALLIS – A new publication from Oregon Sea Grant outlines how that the scarcity of offshore aquaculture programs in the United States – and which are nonexistent in the Pacific Northwest – is creating a seafood trade deficit that is costing the U.S. billions of dollars per year.

The publication, “Offshore Aquaculture in the Pacific Northwest,” was edited by Oregon State University fisheries professor Chris Langdon.

“The United States is far from sufficient in meeting its demands for seafood,” Langdon said. “Forty-five percent of our wild fish stocks are overfished, and we import about 80 percent of our seafood from other countries, at an annual cost of $13 billion. Clearly there is a need to develop additional sources of seafood.”

Offshore aquaculture may eventually prove to be one of those sources.

With support from NOAA and other federal and state agencies, Langdon says, offshore aquaculture projects have been established in a few regions of the United States. However, no such projects have been established in the Pacific Northwest.

Last fall Langdon coordinated a forum at OSU’s Hatfield Marine Science Center exploring the potential of offshore aquaculture in the region. Participating were representatives of state and federal agencies, media, research institutions, and coastal and fishing communities. The Sea Grant publication presents the results of that forum, including recommendations for next steps in the discussion.

Copies of the 24-page publication may be downloaded at no charge from http://seagrant.oregonstate.edu/sgpubs/onlinepubs.html#w08001, or purchased for $3.50 each (plus shipping) from Sea Grant Communications, 541-737-4849.

In addition, individual papers and presentations from Langdon’s offshore aquaculture forum are available as PDF documents and streaming video at http://oregonstate.edu/conferences/aquaculture2008.

Source: 

Chris Langdon,
541-867-0231

Ocean of junk focus of presentation, panel discussion in Newport

NEWPORT, Ore. – Parts of the Pacific Ocean are beginning to resemble a landfill and the increasing accumulation of debris – mainly plastic – is the focus of a special presentation on Monday, April 27, at Oregon State University’s Hatfield Marine Science Center in Newport.

Two environmental activists from the Algalita Marine Research Foundation in California will visit the center as part of their 2,000-mile bicycle tour from British Columbia to Mexico to raise awareness about what some are calling the “North Pacific Garbage Patch.”

Marcus Eriksen and Anna Cummins will speak, present photos and participate in a panel discussion with OSU researchers and community leaders. The presentation runs from 6:30 to 8:30 p.m. in the Hennings Auditorium at the center, and is free and open to the public.

Eriksen and Cummins are perhaps best known for their project to build JUNK, a raft made from 15,000 bottles, which sailed to Hawaii last summer. The Algalita Marine Research Foundation has been studying the accumulation of plastic debris in the ocean and its 2008 survey concluded that the density of plastics in the ocean has doubled in the past 10 years.

The group also found evidence that lantern fish – which are common prey for tuna, salmon and groundfish – are ingesting plastic.

Others participating in the panel discussion include Kim Raum-Suryan, a faculty research assistant with OSU’s Marine Mammal Institute; Gretchen Ammerman, of the North Lincoln Waste District; and Jeff Feldner, a former commercial fisherman now working for Oregon Sea Grant. Other panelists may be added.

The event is sponsored by the Newport chapter of Surfrider Foundation, Friends of the Hatfield Marine Science Center, Oregon Sea Grant, the Oregon Coast Aquarium, and CoastWatch.

More information on the JunkRaft project is available at: http://junkraft.com/home.html

Media Contact: 
Source: 

Bill Hanshumaker,
541-867-0167