OREGON STATE UNIVERSITY

college of agricultural sciences

OSU researchers helping China’s rarest seabird rebound from near-extinction

CORVALLIS, Ore. – A collaborative project between researchers in Asia and Oregon has helped establish a new breeding colony for one of the world’s most endangered seabirds – the Chinese crested tern, which has a global population estimated at no more than 50 birds.

Until this year, there were only two known breeding colonies for the critically endangered species (Thalasseus bernsteini) – both in island archipelagos close to the east coast of the People’s Republic of China. Once thought to be extinct, there were no recorded sightings of Chinese crested terns from the 1930s until 2000, when a few birds were rediscovered on the Matsu Islands.

This summer an innovative tern colony restoration began, with assistance from students and faculty in the Department of Fisheries and Wildlife at Oregon State University. Dan Roby, a professor of wildlife ecology at OSU, had previously led efforts to relocate populations of Caspian terns from locations along the Columbia River in Oregon, where the birds were consuming significant quantities of juvenile salmon.

“The problem was different in Oregon than it is in China, but the goal was the same – to alter the habitat in a good location in hopes of creating a breeding colony,” Roby said. “The methods also were similar and based on tern restoration techniques developed by Steve Kress of the National Audubon Society. You have to partially clear an island of vegetation, place decoys there, and attract birds using sound.”

In early May of 2013, an international team did just that on a small island in the Jiushan Islands called Tiedun Dao. Chinese crested terns used to breed on the archipelago a decade ago, increasing the chances that restoration could be successful there, Roby said.

The project team included members from the Xiangshan Ocean and Fishery Bureau, the Jiushan Islands National Nature Reserve, the Zhejiang Museum of Natural History, and OSU’s Department of Fisheries and Wildlife. The team members cleared brush off Tiedun Dao, place 300 tern decoys on the island, and used solar-powered playback systems to broadcast recorded vocalizations of both greater crested terns and Chinese crested terns.

“Greater crested terns are not endangered and when they establish colonies, it sometimes attracts the endangered Chinese crested tern,” Roby pointed out. “We thought if we could get them in to colonize the island, their numbers would eventually grow and the Chinese crested terns might follow.

“We just didn’t expect it to happen that quickly,” Roby added.

The researchers thought it might take years – but by July, a handful of greater crested terns were spotted flying over the decoys. By the end of that month, 2,600 greater crested terns had been documented and hundreds of pairs had laid eggs and begun incubating them. To the surprise of the restoration team, 19 adult Chinese crested terns were spotted on the island and at least two pairs laid eggs.

It was the highest single count of the endangered seabird in one location since the species’ rediscovery in 2000.

By late September – despite typhoons and a late start to the breeding season – more than 600 greater crested tern chicks, and at least one Chinese crested tern chick had successfully fledged.

Local officials say they are committed to the protection of the emerging colony.

“We will do our best to ensure good management of the Jiushan Islands National Nature Reserve and we also hope to receive more support for the conservation of the tern colony here in Xiangshan,” said Yu Mingquan, deputy director of the provincial Xiangshan Ocean and Fishery Bureau.

The success of the colony on Tiedun Dao is a “landmark for contemporary conservation in the region,” said Simba Chan, the senior Asia conservation officer for Birdlife. “No one dared imagine that the first year of such a challenging restoration project would be so successful.”

Funding for the project was provided by numerous sources internationally.

Media Contact: 
Source: 

Dan Roby, 541-737-1955; Daniel.Roby@oregonstate.edu

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OSU joins NASA mission to measure carbon in ocean plants and ecosystems

CORVALLIS, Ore. – As part of a NASA air and sea mission, Oregon State University researchers will measure ocean plants to see how changes in carbon levels could affect the future of fisheries and marine life.

Setting sail from Rhode Island on July 18, the Ship-Aircraft Bio-Optical Research (SABOR) campaign will use new optical instruments to pinpoint carbon levels in phytoplankton – tiny plants that play a critical role in carbon cycling. Phytoplankton absorb carbon dioxide during photosynthesis, distribute it when eaten by fish and other marine life, and then act as a carbon sink when they die and drift into the deep sea.

"Phytoplankton are the base of the marine food web and critical to the overall health of the Earth," said Mike Behrenfeld, one of the SABOR project scientists and a botany and plant pathology professor in OSU's College of Agricultural Sciences. “Changes to these microscopic plants – including the carbon they absorb – can affect an entire ocean, from sardine populations, to the location of native birds, and even to decreases in the survival of marine mammals.

"Understanding changes to phytoplankton biomass and photosynthesis are critical for projecting how oceans will fare in the future and how much of it is related to climate change," added Behrenfeld, who specializes in marine algae research.

The 20-day study has the team sailing and flying around the continental shelf off the East Coast of the United States. SABOR is unique among NASA projects because scientists will measure the ocean from both the air and water and try to find relationships between the two datasets. NASA will use the information to guide future satellite missions for understanding how the ocean and atmosphere are affected by climate.

The expedition will feature a state-of-the-art instrument that Behrenfeld's research team is using to separate phytoplankton from other particles in ocean water, such as bacteria, dead mass, and other types of plankton. The device, known as a sorting flow cytometer, uses a laser to detect phytoplankton in small streams of seawater. It then separates out the tiny plants to be analyzed for carbon. The technique is providing the first direct measurements of organic carbon in phytoplankton, said Behrenfeld.

While the Behrenfeld team is making measurements on the ship, an airplane will be collecting additional data, using an advanced laser system that can penetrate the ocean and measure phytoplankton levels in the upper depths of the water.

“By taking measurements using both the air and water instruments, scientists can gather a more accurate dataset than if they just used one or the other method," said Behrenfeld. "These relationships are the first step toward satellite technology that can provide an improved understanding of ocean ecology and its role in the carbon cycle.

"Eventually, new satellite missions will determine how and why ocean ecosystems are changing and the consequences to fish and the climate," Behrenfeld added.

The Behrenfeld research group is teaming with Kimberly Halsey, a microbiology professor with a joint appointment in OSU's College of Science and the College of Agricultural Sciences, to further understand how changes in phytoplankton numbers are related to their photosynthesis and general health. The two OSU teams include Allen Milligan, Jason Graff, Nerissa Fisher, and Matthew Brown.

SABOR is funded by the Ocean Biology and Biogeochemistry Program at NASA Headquarters, Washington. Project management and support will be provided by the Earth Science Project Office at NASA. Other mission scientists hail from the University of Maine; NASA's Langley Research Center; NASA's Goddard Institute for Space Studies; the City College of New York and others.

Media Contact: 
Source: 

Mike Behrenfeld, 541-737-5289;

Kimberly Halsey, 541-737-1831;

NASA contact: Steve Cole, 202-358-0918

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NASA's Endeavor research vessel

NASA's Endeavor will be a floating laboratory for OSU scientists collecting data on carbon in tiny ocean plants. (Photo by Tom Glennon/University of Rhode Island)

NASA's SABOR flight and ship paths

The expected path of the Endeavor (red) and NASA's aircraft (yellow) show how researchers will coordinate measurements from the ocean and air. (Photo by NASA/Goddard Space Flight Center Scientific Visualization Studio)

Questions and answers on pest management from OSU experts

CORVALLIS, Ore. – What to do about garden pests, including insects, plant diseases and weeds, can be a challenge for gardeners who want to effectively manage the pests without damage to the environment and human health.

The question-and-answer series below illustrates a strategy called Integrated Pest Management, a systematic approach to identify pests and use tactics that are cultural, physical, biological or chemical.

The least toxic and effective methods are always considered first, according to Oregon State University researchers Andy Hulting, a weed control specialist, and Gail Langellotto, an entomologist.

Q: How do I know if I have pest problems in my garden?

A: Check your plants regularly for pest damage such as missing leaves, flowers or fruit or changes in color, texture or size. Most plant problems in home gardens are caused by poor growing conditions, temperature extremes, poor water management or compacted soil. Look under leaves and use a flashlight after dark, which is when many insects are active.

Q: How do I identify what is causing the problem?

A: Often it's not a pest, but another problem such as sun scald or nutrient deficiencies. "Don't apply pesticides without understanding the problem you are trying to solve," Langellotto advised. "Many insects are beneficial and actually help gardens grow better. Others do no damage." Some insect pests can be dislodged with simple methods such as shaking the plant or spraying with a high-pressure stream of water.

Your local OSU Extension office and its Master Gardeners can help correctly identify the culprit and at what point in the pest's life cycle it is most susceptible to control measures.

Q: What pest management tool should I use?

A: Integrated Pest Management utilizes a combination of methods to keep pest populations at an acceptable level, with the least toxic and effective first.

  • Cultural methods: Choose healthy plants that are not prone to pest problems, plant them where they will grow well and rotate where annuals are planted to avoid buildup of disease populations.
  • Physical methods: Pull or dig weeds and hand-pick or trap insect pests off of plants. Row covers designed to extend the gardening season have been found to also keep insect pests away from plants.
  • Biological methods: Garden plants can attract beneficial insects, such as parasitic wasps and green lacewings, to help keep pests at bay. Some of the more common ones are alyssum, coreopsis and sunflower.  The flowers of plants in the Apiaceae family (including carrots, parsnips, celery, parsnip, cilantro and dill) are known to be especially good at attracting parasitic wasps and other beneficial insects.

Q: When and how should I use chemical methods?

A: Some pest problems are difficult to manage without chemical pesticides.  However, chemicals can affect human health and be toxic to other organisms. Thus, use them judiciously and only after you are confident you have identified the pest, have chosen an appropriate pesticide, and that other methods are not likely to provide acceptable levels of control.  Read all label directions before choosing and using pesticides in the garden. 

"If you want to utilize biological controls in the garden, avoid broad-spectrum insecticides whenever possible," Langellotto said. "They may help you manage your insect pests, but they also kill other insects they contact, including beneficial ones."

Q: What precautions should I take with chemical pesticides?

A: If you decide to use a chemical, check the label to make sure your intended use or site is included on the label. Then choose one that is least harmful to the environment and to the applicator, specific to the pest and least harmful to beneficial organisms.

Pesticides labeled "Caution" are the least toxic to humans, "Warning" are more toxic, and "Danger-Poison" (with a skull and crossbones), are the most toxic. The law requires that you read the label. Be sure to wear protective clothing, especially eye protection, gloves and long pants.

Pesticides are more concentrated than they used to be, according to Hulting, and are made for very specific uses. "You might need only a fraction of an ounce to treat a large area or number of plants, perhaps less than in previous years," he said. "Don't use more product than the label specifies. More is not better."

Q: Where can I get more specific information?

A: For fact sheets, frequently asked questions and podcasts on pesticide use, check online at http://npic.orst.edu/ or call the National Pesticide Information Center at OSU at 1-800-858-7378.

Media Contact: 
Source: 

Gail Langellotto, 541-737-5175;

Andy Hulting, 541-737-5098

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Green lacewing

As green lacewing larvae grow, they benefit gardens by eating immature pests. (Photo by Lynn Ketchum.)

Artisan cheese startups face six-digit costs, finds OSU study

CORVALLIS, Ore. – Aspiring artisan cheese makers should be prepared to shell out at least $250,000 to set up operations, according to an Oregon State University study.

OSU researchers developed a tool for predicting artisan cheese startup and operating costs based on a number of factors, including types of milk (like goat, cow and sheep), cheese types (such as cheddar, blue and mozzarella), labor expenses, creamery location, marketing; and even the fuel needed to transport products to farmers markets.

"We wanted to give cheese entrepreneurs a realistic idea about what they're getting into," said Lisbeth Goddik, a food science and technology professor in OSU's College of Agricultural Sciences and co-author of the study. “In this industry, lack of economic data has sometimes made it difficult to craft a business plan, obtain financing and plan for the future.”

OSU's study is the first to estimate costs for Oregon artisan cheese makers, Goddik pointed out. OSU researchers interviewed large- and small-scale cheese companies in Oregon and studied their expenses.

They found that a large-scale artisan cheese company producing 60,000 pounds a year faces startup costs of $623,874, assuming the company purchases its own processing and aging facilities. First-year operation costs are an additional $620,094, the researchers estimated.

A smaller operation producing 7,500 pounds a year would spend about $267,248 to set up processing and aging operations, with a first-year production cost of $65,245.

"Since profits are unlikely in the first few years, access to sufficient capital is critical to survival," said Cathy Durham, an applied economics professor at OSU who works at OSU's Food Innovation Center in Portland. She also is a co-author of the study.

"Despite the challenges,” Goddik added, “the industry is active.”

In Oregon, the number of artisan cheese manufacturers jumped from three in 1999 to 20 in 2014, according to dairy plant licenses with the Oregon Department of Agriculture (ODA).

OSU's economic model is adaptable so cheese makers around the world can tailor it to their location and account for other attributes that affect cost. OSU researchers have used the tool in consulting with Oregon cheese startups, as well as artisan cheese entrepreneurs from Canada, Europe and New Zealand.

Goddik provides training for all levels of artisan cheese makers, including improvements in product quality, shelf life and safety. She consults closely with them to solve specific challenges and serves as a technical liaison with the ODA's Food Safety Division.

Goddik, Durham and former OSU graduate student Andrea Bouma co-authored the study, which was published in the Journal of Dairy Science. The study was funded by the Eckelman Endowment at OSU.

Media Contact: 
Source: 

Lisbeth Goddik, 541-737-8322; Cathy Durham, 503-872-6671

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Artisan cheese

Five-pound rounds of "Sublimity" cheese sit in an aging facility at the Oregon Gourmet cheese plant in Albany, Oregon. (Photo by Lynn Ketchum.)

Artisan cheese

Cheese ages at Goldin Artisan Goat Cheese in Molalla. Oregon is home to 20 artisan cheese manufacturers. (Photo by Tiffany Woods.)

OSU's Food Innovation Center to showcase local food entrepreneurs

PORTLAND, Ore. – Local food entrepreneurs will show off their unique creations to the public at a free farmers market-like event at the Food Innovation Center in Portland on June 24.

The inaugural Time To Market Trade Show, which will take place from 4-7 p.m., offers a delicious array of free samples, including crème brûlée, gelato, pickles, peppers, cocktails and health foods. Gluten-free, diabetic-friendly and vegan options will be available. Consumers can buy the products, too.

"This is the public's first chance to get a taste of what we've cooked up with our students," said Sarah Masoni, the center's product development manager. "This event is a perfect way for us to reach out to businesses we've helped over the years and treat the taste buds of Oregon."

The Food Innovation Center is a collaborative effort between Oregon State University and the Oregon Department of Agriculture. It is located at 1207 N.W. Naito Parkway in Portland. For more information, call 503-872-6680.

The vendors are graduates of the Getting Your Recipe to Market class, which OSU faculty help teach. Students learn how to turn their recipes into commercial-ready products by developing business and marketing plans, crafting elevator pitches, solving packaging and food safety issues, and meeting one-on-one with retail buyers.

In the hours preceding the trade show, each exhibitor will meet privately with interested investors, distributors and local retail buyers – a valuable networking opportunity, Masoni said. These food industry partners are able to place products in stores, restaurants, hospitals, college campuses and large companies, such as Intel and Nike.

The center plans to host similar showcases each month this summer, recruiting from among its 200-plus alumni. The June 24 event will also feature a sign-up sheet for potential participants.

"We'd love to see our whole parking lot filled with booths of graduated students," said Masoni, who is also a food products specialist with the OSU Extension Service.

Getting Your Recipe to Market is a collaborative effort between OSU, Portland Community College's Small Business Development Center and New Seasons Market, a regional grocer. Now in its sixth year, the class runs 14 weeks at PCC and is also offered online as a series of four courses offered through OSU's Professional and Continuing Education unit.

Media Contact: 
Source: 

Sarah Masoni, 503-872-6655

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Food Innovation Center

Open in downtown Portland since 1999, the Food Innovation Center helps create food products using Northwest ingredients. (Photo by Lynn Ketchum.)

OSU food entrepreneur

Oregon State University's Food Innovation Center helped Connie Rawlings-Dritsas develop formulas for her line of flavored vinegars. (Photo by Stephen Ward.)

OSU's food preservation and safety hotline opens July 14

CORVALLIS, Ore. – The Oregon State University Extension Service's food preservation and safety hotline will help Oregonians safely can and preserve their garden's abundance again this summer.

The toll-free hotline at 1-800-354-7319 is available July 14 to Oct. 17 from 9 a.m. to 4 p.m. Monday through Friday.

The hotline remains a useful resource for food safety information even in the Internet age, said Nellie Oehler, a faculty member with the OSU Extension Service's Family and Community Health program and Master Food Preserver coordinator in Lane County.

"There's a lot of misinformation online and you have to know the right websites to get accurate information or you could literally kill yourself if you use techniques that are not safe," Oehler said. "People call us to get reliable information from a real person. The Lane and Douglas County Master Food Preservers who answer the calls have good training and years of experience canning and preserving food."

Like all Extension-certified Master Food Preservers, those who staff the hotline have completed 40 hours of training and agreed to spend a similar amount of time sharing their new knowledge with the public. Last year, 460 new and veteran Master Food Preservers throughout the state volunteered more than 20,000 hours of their time on the statewide hotline and at workshops and exhibits.

Master Food Preservers answered 2,262 calls during the 2013 summer season. About 80 percent of those dealt with food safety questions. Typical questions include where to get pressure gauges tested, how long in advance you can cook chicken before the big family picnic and whether grandma's canning recipe is still safe.  

For more information, go to the OSU Extension website on food preservation at http://bit.ly/YqgsFE. OSU Extension's Ask an Expert service also takes online questions about food preservation. Master Food Preservers also run a holiday food safety hotline every November. Find more information about the Master Food Preserver program at http://extension.oregonstate.edu/fch/volunteer-programs.

Media Contact: 
Source: 

Nellie Oehler, 541-757-3937

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Pryse_0419

Michele Pryse, a Master Food Preserver trained by the Oregon State University Extension Service, teaches food preservation techniques and safety guidelines to clients in the Medford area. (Photo by Lynn Ketchum.)

Genome could unlock eucalyptus potential for paper, fuel and fiber

CORVALLIS, Ore. – In a collaboration spanning five continents, scientists have announced the complete sequencing of one of the world’s most widely planted trees, Eucalyptus grandis.

Used for fuel and timber, the species is valued for fast growth and straight grain. Grown usually as a hybrid, it is one of more than 500 species of eucalyptus trees and shrubs that provide a renewable source of fiber, pulp, biofuel material, and medicinal and industrial oils. The accomplishment was published today in the scientific journal Nature.

On the research team were 12 Oregon State University scientists, including plant biologist Pankaj Jaiswal. "This genome sequence will help usher in a new era for studying the biology of the eucalyptus tree. Our advances in understanding could help redefine the possibilities of improving biomass yield, stress tolerance and other traits," said Jaiswal, a botany and plant pathology professor in OSU's College of Agricultural Sciences.

Jaiswal and his colleagues used the high-performance computing facility in Oregon State’s Center for Genome Research and Biocomputing to assign functions to the tree's 36,000-plus genes. They identified which genes correspond to biological processes that underpin control of growth rate, wood hardness, flowering and other attributes.

Plant breeders can use the eucalyptus genome to enhance or suppress traits in the tree, Jaiswal added. For example, breeding for more lignin, which confers strength to woody tissue, can produce wood better suited for furniture. Trees with less lignin could require less energy and fewer chemicals needed to make paper from eucalyptus pulp.

For breeding purposes, one of the most significant accomplishments stems from understanding the genes associated with flowering. Eucalyptus trees generally take three to 10 years to flower after they are propagated from seed, a process that slows the rate of breeding considerably, said Steve Strauss, a co-author of the Nature paper and an Oregon State distinguished professor of forest biotechnology in the College of Forestry.

Strauss has already shown that activating genes responsible for flower development can accelerate flowering. "By accelerating the speed of eucalyptus flowering, plant breeders can shorten generation time for developing new varieties with improved traits," he said.

Researchers can also use the floral gene sequences to prevent or disrupt flowering. That technology could help stop the undesirable spread of the tree and prevent it from becoming invasive.

The study is also leading to a better understanding of the evolutionary relationships of eucalyptus and its relatives. OSU professors Joseph Spatafora and Aaron Liston worked with Jaiswal to redefine the placement of eucalyptus in plant classification. "We managed to reassign its position in the evolutionary tree of life," said Liston.

“The genome provides a better roadmap for breeders to follow, although there is still a long road ahead of us to adapt the plant to all of our desired uses,” he added.

A research group from South Africa, led by Alexander Myburg of the Forestry and Agricultural Biotechnology Institute at the University of Pretoria, supplied the eucalyptus tissues and RNA sequenced by Oregon State.

Collaborating in the research were 80 scientists in South Africa, Brazil, North America, Europe and Australia (where eucalyptus originated). Among the funding sources were Oregon State University, the Tree Biosafety and Genomics Research Cooperative and the National Science Foundation. A contribution by the U.S. Department of Energy Joint Genome Institute was supported by the DOE Office of Science.

Other OSU researchers contributing to the project were: Sushma Naithani, Justin Elser, Rajani Raja and Palitha Dharmawardhana in the Department of Botany and Plant Pathology in the College of Agricultural Sciences; Martin Ranik, Vindhya Amarasinghe and Kelly Vining in the College of Forestry; Alexander E. Boyd and Christopher Sullivan in the Center for Genome Research and Biocomputing.

A genome browser and further information on the project are available at http://www.phytozome.net/eucalyptus.php.

Media Contact: 
Source: 

Pankaj Jaiswal, 541-737-8471; Steve Strauss, 541-737-6578; Joseph Spatafora, 541-737-5304; Aaron Liston, 541-737-5301

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Eucalyptus logs await shipment at a plantation in Brazil. (Photo by Steve Strauss.)


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Plant breeders grow eucalyptus seedlings at a nursery in Brazil. (Photo by Steve Strauss)

OSU calculator helps organic farmers use fertilizer more efficiently

CORVALLIS, Ore. – Organic farmers use cover crops and organic fertilizers, compost and other amendments to add nutrients to their soil. But are they getting the best bang for their buck?

A new online tool from the Oregon State University Extension Service does the math so that small-scale organic farmers can figure that out more precisely. Nick Andrews, an instructor with the OSU Extension Service's small farms program, helped develop the free, spreadsheet-based tool, which is called the Organic Fertilizer and Cover Crop Calculator, at http://smallfarms.oregonstate.edu/calculator.

"The calculator lets you estimate how much nitrogen and other nutrients your cover crops and fertilizers will provide for your next cash crop," Andrews said. "That could help you cut back on fertilizer use and benefit from your soil building practices."

Farmers can save money on fertilizer, while also using this information to reduce the risk of nutrient runoff into waterways, Andrews said. On the flip side, farmers might discover that they're not using enough fertilizer, he said.

Farmers and gardeners who don't use cover crops can still use the calculator to determine which types and amounts of organic and synthetic fertilizers to use.

The new calculator estimates the amount of nitrogen needed in pounds per 1,000 square feet while taking into account the amount of nitrogen added by cover crops and other soil amendments such as compost. The original 2010 calculator made calculations on a per acre basis.

This new calculator is most useful for small-scale farmers and experienced gardeners who are interested in refining their fertilizer programs. Before using the calculator, be sure to sample your soil. The calculator helps you account for legume cover crop nitrogen contributions and select the most cost-effective fertilizers, Andrews said.

Read more about cover crops, soil fertility and soil labs in the following Cooperative Extension publications.

Media Contact: 
Source: 

Nick Andrews, 503-678-1264

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Yfarm_0225

Oregon State University has developed a new spreadsheet-based tool that will allow small-scale organic farmers to more accurately estimate nutrient contributions from cover crops and fertilizers. (Photo by Lynn Ketchum.)

Iron, steel in hatcheries may distort magnetic “map sense” of steelhead

CORVALLIS, Ore. – Exposure to iron pipes and steel rebar, such as the materials found in most hatcheries, affects the navigation ability of young steelhead trout by altering the important magnetic “map sense” they need for migration, according to new research from Oregon State University.

The exposure to iron and steel distorts the magnetic field around the fish, affecting their ability to navigate, said Nathan Putman, who led the study while working as a postdoctoral researcher in the Department of Fisheries and Wildlife, part of OSU’s College of Agricultural Sciences.

Just last year Putman and other researchers presented evidence of a correlation between the oceanic migration patterns of salmon and drift of the Earth’s magnetic field. Earlier this year they confirmed the ability of salmon to navigate using the magnetic field in experiments at the Oregon Hatchery Research Center. Scientists for decades have studied how salmon find their way across vast stretches of ocean.

“The better fish navigate, the higher their survival rate,” said Putman, who conducted the research at the Oregon Hatchery Research Center in the Alsea River basin last year. “When their magnetic field is altered, the fish get confused.”

Subtle differences in the magnetic environment within hatcheries could help explain why some hatchery fish do better than others when they are released into the wild, Putman said. Stabilizing the magnetic field by using alternative forms of hatchery construction may be one way to produce a better yield of fish, he said.

“It’s not a hopeless problem,” he said. “You can fix these kinds of things. Retrofitting hatcheries with non-magnetic materials might be worth doing if it leads to making better fish.”

Putman’s findings were published this week in the journal Biology Letters. The research was funded by Oregon Sea Grant and the Oregon Department of Fish and Wildlife, with support from Oregon State University. Co-authors of the study are OSU’s David Noakes, senior scientist at the Oregon Hatchery Research Center, and Amanda Meinke of the Oregon Hatchery Research Center.

The new findings follow earlier research by Putman and others that confirmed the connection between salmon and the Earth’s magnetic field. Researchers exposed hundreds of juvenile Chinook salmon to different magnetic fields that exist at the latitudinal extremes of their oceanic range.

Fish responded to these “simulated magnetic displacements” by swimming in the direction that would bring them toward the center of their marine feeding grounds. In essence, the research confirmed that fish possess a map sense, determining where they are and which way to swim based on the magnetic fields they encounter.

Putman repeated that experiment with the steelhead trout and achieved similar results. He then expanded the research to determine if changes to the magnetic field in which fish were reared would affect their map sense. One group of fish was maintained in a fiberglass tank, while the other group was raised in a similar tank but in the vicinity of iron pipes and a concrete floor with steel rebar, which produced a sharp gradient of magnetic field intensity within the tank. Iron pipes and steel reinforced concrete are common in fish hatcheries.

The scientists monitored and photographed the juvenile steelhead, called parr, and tracked the direction in which they were swimming during simulated magnetic displacement experiments. The steelhead reared in a natural magnetic field adjusted their map sense and tended to swim in the same direction. But fish that were exposed to the iron pipes and steel-reinforced concrete failed to show the appropriate orientation and swam in random directions.

More research is needed to determine exactly what that means for the fish. The loss of their map sense could be temporary and they could recalibrate their magnetic sense after a period of time, Putman said. Alternatively, if there is a critical window in which the steelhead’s map sense is imprinted, and it is exposed to an altered magnetic field then, the fish could remain confused forever, he said.

“There is evidence in other animals, especially in birds, that either is possible,” said Putman, who now works for the National Oceanic and Atmospheric Administration. “We don’t know enough about fish yet to know which is which. We should be able to figure that out with some simple experiments.”

Media Contact: 
Source: 

Nathan Putman, 205-218-5276 or Nathan.putman@gmail.com; or David Noakes, 541-737-1953, David.noakes@oregonstate.edu

Blueberries coated in leaf extracts have longer shelf life

CORVALLIS, Ore. – An Oregon State University researcher has helped discover a substance in blueberry leaves – which are usually wasted – that can be added to berry coatings, extending their shelf life while adding antioxidants.

Working with an international team of scientists in China, OSU food scientist Yanyun Zhao found that an edible coating containing blueberry leaf extracts helped delay decay and retain water, which slowed down their natural deterioration. The extra weight could also mean extra cash for growers, because blueberries are often sold by volume.

The natural coatings can allow fresh blueberries to be washed and prepared as ready-to-eat products. Most blueberries in stores are unwashed because rinsing them removes their natural waxy coating that preserves the fruit.

"Normally, blueberry leaves fall to the ground as waste," said Zhao, a food science and technology professor in OSU's College of Agricultural Sciences. “We've discovered a use that can change how the berries are stored, sold, as well as increasing their nutritional value.”

Blueberry leaves, which have been used as an herbal remedy, contain high levels of antioxidant phenolics – chemical compounds with antimicrobial properties that protect against fungi and bacteria, such as E. coli and Salmonella.

To create the coatings, researchers mixed these phenolic extracts with chitosan, a natural preservative that comes from crustacean shells. OSU tested coatings made from leaves that were picked at different stages of berry maturity, and leaf extracts were formulated into five different coating treatments based on varying levels of phenols.

Blueberries were dipped in the liquid coating and then dried at room temperature to form dried coatings. Nozzles can also spray the coatings on the surface of the berries as they pass by on a conveyor belt, according to Zhao, a value-added food products specialist with the OSU Extension Service.

Coating the blueberries will add to their cost, she said, although it's unclear how much.

The research was conducted in collaboration with scientists in China, including Yun Deng, at Shanghai Jiao Tong University at the school's Bor Luh Food Safety Center, and published in the journals of Food Control and Postharvest Biology and Technology.

Media Contact: 
Source: 

Yanyun Zhao, 541-737-9151

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Blueberries

To create edible coatings, researchers mixed extracts from blueberry leaves with chitosan, a natural preservative that comes from crustacean shells. (Photo by Lynn Ketchum.)