OREGON STATE UNIVERSITY

marine science and the coast

Heceta Head Coastal Conference set Oct. 26-27

FLORENCE, Ore. – Global connections across the Pacific Ocean in science, economics and policies – and how these things affect Oregon's ocean – are the focus of the eighth annual Heceta Head Coastal Conference, Oct. 26-27 at the Florence Events Center.

Scientists, policy-makers and community leaders – including Oregon first lady Cylvia Hayes and Oregon State University marine mammal specialist Bruce Mate – will address the theme “Oregon's Oceans: Bringing the High Seas Home” during the two-day conference, which is open to the public.

Hayes will kick off the conference with a dinner speech on “Healthy Ocean, Healthy Economy, Healthy Oregon” at 5 p.m. Friday.

Saturday's talks and panels include a number of OSU researchers, including oceanographer Jack Barth, marine zoologist Francis Chan, sociologist Flaxen Conway, and fisheries ecologist Jessica Miller. Also speaking will be Oregon Rep. Arnie Roblan and representatives of the Pacific Shellfish Growers' Association, the Sustainable Fisheries Partnership and the Pacific States Marine Fisheries Commission on topics ranging from the migration of albacore tuna to the challenges and opportunities facing Oregon's coastal communities to the international laws governing use of the oceans.

The afternoon will include panel discussions on hypoxia and ocean acidification in the Pacific, and tsunami debris.

Mate, chair of the OSU Marine Mammal Institute, will close out the conference with a keynote speech on whale migrations and critical habitats.

Registration is $25 for Friday's dinner and $35 ($25 for students) for Saturday's sessions, including lunch. For registration and other details, including information about discounted overnight lodging in Florence, visit http:www.hecetaheadconference.org

The conference is organized by Heceta Head Coastal Conference, Inc. in partnership with Oregon Sea Grant.

 

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Jamie Doyle, 541-572-5263 ext. 288

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

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

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

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

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

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

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

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

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

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Joe Tyburczy, 541-231-9780

OSU to lead project exploring ocean’s response to increasing acidification

CORVALLIS, Ore. – A West Coast network of researchers has received a grant of nearly $1.1 million from the National Science Foundation to analyze the ecological and biological response to ocean acidification in the California Current System.

Oregon State University is the lead institution on the project, which also includes researchers from the University of California, Davis; Monterey Bay Aquarium Research Institute; University of California, Santa Cruz; University of Hawaii, Manoa; and University of California, Santa Barbara.

The researchers will focus much of their attention on a mussel, Mytilus californianus, a widespread component of the rocky intertidal zone and an important test subject for understanding ocean chemistry changes. Their previous research found that the growth, survival and shell strength of the mussel larvae are significantly affected in a negative way by elevated levels of carbon dioxide in the ocean water.

“We know that increasing ocean acidification has the potential to threaten the viability of mussels and other shellfish,” said Bruce Menge, a distinguished professor of zoology at Oregon State and principal investigator on the project. “In this new effort, we will explore when negative impacts begin to occur and how the organisms actually respond in different environments, whether localized or large-scale.”

The researchers will conduct field and laboratory experiments across a network of 10 near-shore ocean acidification monitoring sites that span 1,400 kilometers of the coastline. By combining experiments with a sensor network that will continuously measure ocean pH changes, the researchers will be able to examine the sensitivity and potential resilience to ocean acidification among mussel populations that are spread along much of the West Coast of the United States.

Co-principal investigators on the project include Jack Barth, OSU College of Earth, Ocean, and Atmospheric Sciences, and Francis Chan, an ecologist in the OSU College of Science.

Menge, Barth and Chan are principal investigators with PISCO, the Partnership for Interdisciplinary Studies of Coastal Oceans, which also is a multi-institution research effort led by Oregon State. During the past several years, they have documented and helped explain increasing incidence of hypoxia, or low-oxygen water, in the near-shore ocean off Oregon, which has led to biological “dead zones.”

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Bruce Menge, 541-737-5358

OSU, City of Newport plan for exhibit featuring piece of tsunami dock

NEWPORT, Ore. – A section from a huge dock that ripped loose from its moorings in the northern Japanese city of Misawa during the massive earthquake and tsunami in March of 2011 will become part of an exhibit in Newport, Ore., just a few miles from where it washed ashore in early June of this year.

The dock, which became an instant tourist attraction for several weeks, has since been dismantled. But a piece of the huge structure has been saved and will be on display at Oregon State University’s Hatfield Marine Science Center by early next year.

The City of Newport is providing initial funding for the project and Mayor Mark McConnell hopes donations will fill the gaps. When finished, the dock section will be mounted outside of the HMSC Visitor Center, accompanied by educational signage as well as a memorial plaque. The exhibit is being developed by Oregon Sea Grant, which manages the Visitor Center, and will serve as the start of an eventual interpretive trail built along the tsunami evacuation route from the OSU center to higher ground.

“That would certainly be fitting,” said McConnell, who visited Sendai, Japan, last summer. “The devastation we saw in Japan was incredible. You realize when you see it first-hand that you can’t plan or build for an event of that magnitude, but you can prepare for it by educating yourself about the risks and creating strategies for safe evacuation.

“The exhibit will be a reminder that the tragedy in Japan could just as easily happen here,” he added.

Shawn Rowe, an OSU free-choice learning specialist based at the Hatfield Marine Science Center, said the focus of the planned exhibit’s educational effort will be on tsunami awareness, the risk of invasive species from the tsunami debris, and how the dock got here in the first place.

“It is a good opportunity to broaden public awareness about such issues,” said Rowe, who works for Oregon Sea Grant. “This was a unique event. Certainly, materials float over from Japan quite often. But rarely, if ever, have we seen a confluence of circumstances that led to the dock arriving in Newport, Ore.”

Fishing floats, logs and debris arrive on the West Coast from Asia with some regularity, but rarely does a structure this large that had been anchored for years in an inlet in Japan – and thus accumulating local seaweeds and organisms – rip loose and journey across the ocean.

“What was surprising to us is that so many of the plants and animals that were attached to the dock survived the 15-month journey across the Pacific Ocean,” said Jessica Miller, an OSU marine ecologist who has studied the dozens of plant and animal species on the dock. “What we don’t yet know is whether these species have established themselves in local waters with the potential to become invasive.”

Mark Farley, who manages the HMSC Visitor Center, said the dock section will be delivered to Newport in the next few weeks, and work on the foundation for the display and signage will continue into the early part of 2013.

“Our hope is to have the exhibit open to the public by the anniversary of the earthquake and tsunami next March,” Farley said.

For more information on donating to the Japanese dock exhibit at OSU’s Hatfield Marine Science Center, go to: http://hmsc.oregonstate.edu/visitor/get-involved/donate, or call Mark Farley at 541-867-0276.

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Shawn Rowe, 541-867-0190

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Program to monitor harmful algal blooms to end next month

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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Angel White, 541-737-6397

Coastal visitors may encounter whales – but what kind are they likely to be?

NEWPORT, Ore. – For the past several weeks, gray whales that spent the spring breeding or calving in the waters off Mexico have been arriving in the Pacific Northwest to feed for the summer and fall, including areas along the Oregon coast.

The gray whales often are visible to coastal visitors from the bluffs along Highway 101, or to ocean fishing enthusiasts pursuing salmon, halibut or other fish. Whale-watching tours available in many coastal ports introduce hundreds of tourists to migrating and resident whales.

But gray whales aren’t the only species of whale that can be seen off Oregon, according to experts at Oregon State University’s Marine Mammal Institute.

“You can sometimes spot humpback whales and blue whales along the coast, but typically they are further from shore,” said Barb Lagerquist, who does whale research for the institute, located in OSU’s Hatfield Marine Science Center. “Having said that, people last year got a rare peek at blues and humpbacks within a couple of miles of shore off Depoe Bay.”

During migration, gray whales often travel close to shore, with mothers and calves close together, Lagerquist noted, and it isn’t uncommon to see groups of three to five adults together. There is a small population of gray whales – perhaps 200 or so – that feed off the coasts of northern California, Oregon, Washington, British Columbia and southeast Alaska from May to October, rather than migrating to the Arctic. These resident whales are known as the Pacific Coast Feeding Group.

“We have already seen some of these animals along the coast this year,” Lagerquist said. “They feed very close to shore in waters depths of less than 20 meters. We recently saw a mother-calf pair inside the tip of the north jetty in Newport’s Yaquina Bay as we were heading out in our boat.”

Less frequent visitors to Oregon waters are minke whales, which are more common off Asia and in the Arctic, but will occasionally venture within a few miles of shore.

How can you tell what kind of whale you’re seeing? Lagerquist said the keys to whale identification are body size, color, the presence or absence of dorsal fins, and the position and shape of the dorsal fins. Most whales seen off Oregon will be grays, she added, especially close to shore.

Here is a link to some photos from OSU’s Marine Mammal Institute: http://bit.ly/Mu5Zm8

Gray whales: Adult gray whales are about 35 to 45 feet in length, and are a mottled gray in color with occasional white spots and white barnacle scars. They usually have patches of barnacles and whale lice on their bodies.

Gray whales don’t have a dorsal fin, but have dorsal “knuckles” – a series of bumps protruding from their back and extending along their tail. “The first knuckle can be quite large and look like a small dorsal fin,” Lagerquist said.

Humpback whales are slightly bigger than grays – about 40 to 50 feet in length – and are dark gray or even black in color. They have very long, narrow “wing-like” pectoral fins, which can be white on the underside. Humpbacks also have a small, stepped dorsal fin.

Humpbacks are very acrobatic, Lagerquist said, and can often be seen breaching, or propelling almost their entire body out of the water – spinning around and landing on their back or side.

Minkes are the smallest baleen whale, at 23 to 33 feet. They are dark gray to black with white bands on the top of their small pectoral fins – sometimes called “white mittens.” They may also haves a pale gray chevron, or swirling pattern, on their back, and they have a prominent falcate dorsal fin. Sightings of these animals close to Northwest shores are rare.

Blue whales are occasionally seen off the coast and are notable because of their massive size, Lagerquist said. These whales can reach lengths of 75 to 85 feet and weight as much as 240,000 pounds. Blue whales are a mottled bluish-gray color and have a small dorsal fin on the back quarter of their body that may be falfcate, pointed or triangular in shape.

Killer whales may also be seen along the Oregon coast, most commonly in spring months during the gray whale mother/calf migration. Killer whales are not technically whales, but rather the largest member of the dolphin family, reaching 20 to 32 feet in length. They have a striking black and white color pattern, with a white eye patch, a white patch extending from underneath up their sides, and a gray “saddle patch” behind their dorsal fin. Adult males have a very tall, triangular dorsal fin; female dorsal fins are falcate.

Lagerquist reminds coastal visitors that all marine mammals are protected under the Marine Mammal Protection Act of 1972, and it is illegal to harass them. Vessels or people in the water should not approach whales closer than 100 yards. Violators may be subject to fines and/or imprisonment.

More information on whales is available in publications by Oregon Sea Grant at: http://seagrant.oregonstate.edu/sgpubs/collection/marine-animals

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Barb Lagerquist, 541-867-0322

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California Blue Whale
A blue whale off Oregon's coast

Species identified from the Japanese dock that washed ashore

NEWPORT, Ore. – As scientists continue identifying the organisms attached to a floating dock from the 2011 Japanese tsunami that came ashore at Agate Beach just north of Newport, Ore., earlier this month they also are casting a wary eye to the future and what other potential invasive species may arrive.

“The floating dock can be considered a wakeup call that conveniently arrived on the beach within five miles of a leading marine science center,” said Jessica Miller, an Oregon State University marine ecologist who was one of the first scientists to examine the organisms. “This provides us with a spectacular opportunity to understand the overall invasion process and the risks associated with tsunami debris fields to come.”

The Oregon Department of Fish and Wildlife is leading the state’s response to the invasive species threat and coordinating with OSU, state and federal agencies and other partners. ODFW has established a website http://www.dfw.state.or.us/conservationstrategy/invasive_species.asp that keeps the public, scientists and the media informed about best practices for disposing of debris with organisms on it.

The Oregon Invasive Species Council has a hotline for reporting suspected invasive species at 1-866-INVADER.

Miller and colleague John Chapman, who work out of OSU’s Hatfield Marine Science Center, have identified as many as 50 different organisms from the dock, which has definitively been linked to Japan. They are still trying to identify and catalog some of the remaining species.

The fear, researchers say, is the species that arrive on debris from Japan may colonize along the West Coast, which has been most vulnerable to invasive species brought here in the ballast water of ships, as well as by other mechanisms. Tsunami debris is an undocumented, if not new threat for invasives.

“Among the living organisms that we have identified from the dock are some that could aggressively invade local marine environments and threaten native species,” said Chapman an OSU aquatic invasive species specialist from the university’s Department of Fisheries and Wildlife. “The real question is how many of these organisms may have left the dock before it was beached.”

Chapman said some of the species that have the most potential for successful invasion are the Northern Pacific seastar (Asterias amurensis), the Japanese shore crab (Hemigrapsus sanguineus), and a species of brown algae (Undaria pinnatifida), which had covered the dock, which was 66 feet long, 19 feet wide and seven feet high.

Gayle Hansen, an OSU botany and plant pathology specialist, is working with Hiroshi Kawai from Kobe University in Japan on further identification of algal species, and the OSU scientists are also working with Jim Carlton of Williams College to find taxonomic experts to help with identification.

Other organisms aboard the dock include at least eight species of mollusk, an anemone, a sponge, an oyster, a solitary tunicate, a granular claw crab, three or more species of amphipods, four or more species of barnacles and worms, bryozoans, a European blue mussel known as Mytilus galloprovincialis, and a sea urchin.

OSU’s Hatfield Marine Science Center has created a website that has photos of some of the identified species, It can be found at http://blogs.oregonstate.edu/floatingdock

Jack Barth, an OSU oceanographer who specializes in currents, says the dock that arrived at Agate Beach could have landed elsewhere if it had reached nearshore waters a few weeks earlier or later. The key, he said, is how seasonal winds create currents.

“Summertime winds come from the north and push currents south,” Barth said. “Because the Earth is rotating, that pushes things away from the shore and may keep some debris out at sea for a while. But when these northerly winds reverse and become southerly – or just relax and weaken – the surface flow is back on shore and that will bring debris with it.

“After about mid-October, coastal currents will reverse and flow to the north,” Barth added, “so at that point, we can expect more debris to land in Washington and British Columbia.”

Barth said there are some areas of the coast – including near Coos Bay and Winchester Bay – where currents sweep close to shore and may attract more debris. Conversely, he said, debris can get caught in an offshore “convergence zone” and drift hundreds of miles up the coastline before beaching.

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Jessica Miller, 541-867-0381

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New deglaciation data opens door for earlier First Americans migration

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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Nicole Misarti, 541-737-2065

Undersea volcano gave off signals before eruption in 2011

NEWPORT, Ore. – A team of scientists that last year created waves by correctly forecasting the 2011 eruption of Axial Seamount years in advance now says that the undersea volcano located some 250 miles off the Oregon coast gave off clear signals just hours before its impending eruption.

The researchers’ documentation of inflation of the undersea volcano from gradual magma intrusion over a period of years led to the long-term eruption forecast. But new analyses using data from underwater hydrophones also show an abrupt spike in seismic energy about 2.6 hours before the eruption started, which the scientists say could lead to short-term forecasting of undersea volcanoes in the future.

They also say that Axial could erupt again – as soon as 2018 – based on the cyclic pattern of ground deformation measurements from bottom pressure recorders.

Results of the research, which was funded by the National Science Foundation, the National Oceanic and Atmospheric Administration, and the Monterey Bay Aquarium Research Institute (MBARI), are being published this week in three separate articles in the journal Nature Geoscience.

Bill Chadwick, an Oregon State University geologist and lead author on one of the papers, said the link between seismicity, seafloor deformation and the intrusion of magma has never been demonstrated at a submarine volcano, and the multiple methods of observation provide fascinating new insights.

“Axial Seamount is unique in that it is one of the few places in the world where a long-term monitoring record exists at an undersea volcano – and we can now make sense of its patterns,” said Chadwick, who works out of Oregon State’s Hatfield Marine Science Center in Newport, Ore. “We’ve been studying the site for years and the uplift of the seafloor has been gradual and steady beginning in about 2000, two years after it last erupted.

“But the rate of inflation from magma went from gradual to rapid about 4-5 months before the eruption,” added Chadwick. “It expanded at roughly triple the rate, giving a clue that the next eruption was coming.”

Bob Dziak, an Oregon State University marine geologist, had previously deployed hydrophones on Axial that monitor sound waves for seismic activity. During a four-year period prior to the 2011 eruption, there was a gradual buildup in the number of small earthquakes (roughly magnitude 2.0), but little increase in the overall “seismic energy” resulting from those earthquakes.

That began to change a few hours before the April 6, 2011, eruption, said Dziak, who also is lead author on one of the Nature Geoscience articles.

“The hydrophones picked up the signal of literally thousands of small earthquakes within a few minutes, which we traced to magma rising from within the volcano and breaking through the crust,” Dziak said. “As the magma ascends, it forces its way through cracks and creates a burst of earthquake activity that intensifies as it gets closer to the surface.

“Using seismic analysis, we were able to clearly see how the magma ascends within the volcano about two hours before the eruption,” Dziak said. “Whether the seismic energy signal preceding the eruption is unique to Axial or may be replicated at other volcanoes isn’t yet clear – but it gives scientists an excellent base from which to begin.”

The researchers also used a one-of-a-kind robotic submersible to bounce sound waves off the seafloor from an altitude of 50 meters, mapping the topography of Axial Seamount both before and after the 2011 eruption at a one-meter horizontal resolution. These before-and-after surveys allowed geologists to clearly distinguish the 2011 lava flows from the many previous flows in the area.

MBARI researchers used three kinds of sonar to map the seafloor around Axial, and the detailed images show lava flows as thin as eight inches, and as thick as 450 feet.

“These autonomous underwater vehicle-generated maps allowed us, for the first time, to comprehensively map the thickness and extent of lava flows from a deep-ocean submarine in high resolution,” said David Caress, an MBARI engineer and lead author on one of the Nature Geoscience articles. “These new observations allow us to unambiguously differentiate between old and new lava flows, locate fissures from which these flows emerged, and identify fine-scale features formed as the lava flowed and cooled.”

The researchers also used shipboard sonar data to map a second, thicker lava flow about 30 kilometers south of the main flow – also a likely result of the 2011 eruption.

Knowing the events leading up to the eruption – and the extent of the lava flows – is important because over the next few years researchers will be installing many new instruments and underwater cables around Axial Seamount as part of the Ocean Observatories Initiative. These new instruments will greatly increase scientists’ ability to monitor the ocean and seafloor off of the Pacific Northwest.

“Now that we know some of the long-term and short-term signals that precede eruptions at Axial, we can monitor the seamount for accelerated seismicity and inflation,” said OSU’s Dziak. “The entire suite of instruments will be deployed as part of the Ocean Observatories Initiative in the next few years – including new sensors, samplers and cameras – and next time they will be able to catch the volcano in the act.”

The scientists also observed and documented newly formed hydrothermal vents with associated biological activity, Chadwick said. 

“We saw snowblower vents that were spewing out nutrients so fast that the microbes were going crazy,” he pointed out. “Combining these biological observations with our knowledge of the ground deformation, seismicity and lava distribution from the 2011 eruption will further help us connect underwater volcanic activity with the life it supports.”

Scientists from Columbia University, the University of Washington, North Carolina State University, and the University of California at Santa Cruz also participated in the project and were co-authors on the Nature Geoscience articles.

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Bill Chadwick, 541-867-0179

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MBARI map of Axial

MBARI map of lava

 


Boca vent
Snowblower vent

 

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Hydrophone buried by lava

Floating dock from Japan carries potential invasive species

NEWPORT, Ore. – When debris from the 2011 earthquake and tsunami in Japan began making its way toward the West Coast of the United States, there were fears of possible radiation and chemical contamination as well as costly cleanup.

But a floating dock that unexpectedly washed ashore in Newport this week and has been traced back to the Japanese disaster has brought with it a completely different threat – invasive species.

Scientists at Oregon State University’s Hatfield Marine Science Center said the cement float contains about 13 pounds of organisms per square foot. Already they have gathered samples of 4-6 species of barnacles, starfish, urchins, anemones, amphipods, worms, mussels, limpets, snails, solitary tunicates and algae – and there are dozens of species overall.

“This float is an island unlike any transoceanic debris we have ever seen,” said John Chapman, an OSU marine invasive species specialist. “Drifting boats lack such dense fouling communities, and few of these species are already on this coast. Nearly all of the species we’ve looked at were established on the float before the tsunami; few came after it was at sea.”

Chapman said it was “mind-boggling” how these organisms survived their trek across the Pacific Ocean. The low productivity of open-ocean waters should have starved at least some of the organisms, he said.

“It is as if the float drifted over here by hugging the coasts, but that is of course impossible,” Chapman said. “Life on the open ocean, while drifting, may be more gentle for these organisms than we initially suspected. Invertebrates can survive for months without food and the most abundant algae species may not have had the normal compliment of herbivores. Still, it is surprising.”

Jessica Miller, an Oregon State University marine ecologist, said that a brown algae (Undaria pinnatifida), commonly called wakame, was present across most of the dock – and plainly stood out when she examined it in the fading evening light. She said the algae is native to the western Pacific Ocean in Asia, and has invaded several regions including southern California. The species identification was confirmed by OSU phycologist Gayle Hansen.

“To my knowledge it has not been reported north of Monterey, Calif., so this is something we need to watch out for,” Miller said.

Miller said the plan developed by the state through the Oregon Department of Fish and Wildlife and Oregon State Parks is to scrape the dock and to bag all of the biological material to minimize potential spread of non-native species. But there is no way of telling if any of the organisms that hitchhiked aboard the float from Japan have already disembarked in nearshore waters.

“We have no evidence so far that anything from this float has established on our shores,” said Chapman. “That will take time. However, we are vulnerable. One new introduced species is discovered in Yaquina Bay, only two miles away, every year. We hope that none of these species we are finding on this float will be among the new discoveries in years to come.”

The possibilities are many, according to Miller.

“Among the organisms we found are small shore crabs similar to our Hemigrapsus that look like the same genus, but may be a different species,” Miller said. “There were also one or more species of oysters and small clam chitons, as well as limpets, small snails, numerous mussels, a sea star, and an assortment of worms.”

Invasive marine species are a problem on the West Coast, where they usually are introduced via ballast water from ships. OSU’s Chapman is well aware of the issue; for several years he has studied a parasitic isopod called Griffen’s isopod that has infested mud shrimp in estuaries from California to Vancouver Island, decimating their populations.

In 2010, an aggressive invasive tunicate was found in Winchester Bay and Coos Bay along the southern Oregon coast. Known as Didemnum vexillum, the tunicate is on the state’s most dangerous species list and is both an ecological and economic threat because of its ability to spread and choke out native marine communities, according to OSU’s Sam Chan, who chairs the Oregon Invasive Species Council.

It is difficult to assess how much of a threat the organisms on the newly arrived float may present, the researchers say. As future debris arrives, it may carry additional species, they point out. However, this dock may be unique in that it represents debris that has been submerged in Japan and had a well-developed subtidal community. This may be relatively rare, given the amount of debris that entered the ocean, the researchers say.

“Floating objects from near Sendai can drift around that coast for a while before getting into the Kuroshio current and then getting transported to the eastern Pacific,” Chapman said. The researchers hope to secure funding to go to Japan and sample similar floats and compare the biological life on them with that on the transoceanic dock.

The scientists say the arrival of the dock is also a sobering reminder of the tragedy that occurred last year, which cost thousands of lives.

“We have to remember that this dock, and the organisms that arrived on it, are here as a result of a great human tragedy,” Miller said. “We respect that and have profound sympathy for those who have suffered, and are still suffering.”

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