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	<title>Terra Magazine &#187; acoustics</title>
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	<description>A world of research at Oregon State University</description>
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	<itunes:summary>A world of research at Oregon State University</itunes:summary>
	<itunes:author>Terra Magazine</itunes:author>
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	<itunes:subtitle>A world of research at Oregon State University</itunes:subtitle>
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		<title>Terra Magazine &#187; acoustics</title>
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		<title>Dolphins Hunt Together</title>
		<link>http://oregonstate.edu/terra/2011/02/dolphins-hunt-together/</link>
		<comments>http://oregonstate.edu/terra/2011/02/dolphins-hunt-together/#comments</comments>
		<pubDate>Tue, 01 Feb 2011 05:44:10 +0000</pubDate>
		<dc:creator>Terra Staff</dc:creator>
				<category><![CDATA[Departments]]></category>
		<category><![CDATA[Earth]]></category>
		<category><![CDATA[Healthy Planet]]></category>
		<category><![CDATA[Winter 2011]]></category>
		<category><![CDATA[acoustics]]></category>
		<category><![CDATA[Dolphins]]></category>
		<category><![CDATA[Kelly Benoit-Bird]]></category>
		<category><![CDATA[Marine Science & the Coast]]></category>
		<category><![CDATA[Oceanic and Atmospheric Sciences]]></category>

		<guid isPermaLink="false">http://oregonstate.edu/terra/?p=6735</guid>
		<description><![CDATA[Watch spinner dolphins corral their quarry and work together to feed in these animations. Kelly Benoit-Bird used acoustic data of dolphins feeding at night near Hawaii. She reported her findings in the following journal article: Benoit-Bird, K.J. &#038; Au, W.W.L. 2009 “Cooperative prey herding by a pelagic dolphin, Stenella longirostris.” Journal of the Acoustical Society [...]]]></description>
				<content:encoded><![CDATA[<p>Watch spinner dolphins corral their quarry and work together to feed in these animations.  Kelly Benoit-Bird used acoustic data of dolphins feeding at night near Hawaii. She reported her findings in the following journal article: Benoit-Bird, K.J. &#038; Au, W.W.L. 2009 “Cooperative prey herding by a pelagic dolphin, <em>Stenella longirostris</em>.” <em>Journal of the Acoustical Society of America</em>, 125: 539-546, which is available on her <a href="http://people.oregonstate.edu/~benoitbk/pubs.html">website</a>.</p>
<p>Click on the orange text below to see the animations.</p>
<p><a href="http://people.oregonstate.edu/~benoitbk/reprints/Benoit-Bird%20Animation%201.wmv">Top view</a>: Top view of data from a multibeam sonar observations of dolphin  foraging. This animation is a composite of three observations  overlapping in foraging stage to permit a visualization of a complete  foraging bout. Each frame is the composite of six successive sonar  echoes, providing higher resolution and three-dimensional information  while minimizing noise in the data. The strong air cavity echo from each  dolphin is represented by the dots. Isosurfaces of prey scattering  strength identified from spatial statistics are shown in purple with  lighter colors representing higher scattering. The travel of the vessel  has been removed and the data is shown at 8 times real time.</p>
<p><a href="http://people.oregonstate.edu/~benoitbk/reprints/Benoit-Bird%20Animation%202.wmv">Side view</a>: Side view of data from a multibeam sonar observation of a foraging  dolphins. This animation is a composite of three observations  overlapping in foraging stage to permit a visualization of a complete  foraging bout. Each frame is the composite of six successive sonar  echoes, providing higher resolution and three-dimensional information  while minimizing noise in the data. The strong air cavity echo from each  dolphin is represented by the dots. Blue dots show dolphins behind the  center of the circle and yellow represent dolphins in front of this  plane. Isosurfaces of prey scattering strength identified from spatial  statistics are shown in purple with lighter colors representing higher  scattering. The travel of the vessel has been removed and the data is  shown at 8 times real time.</p>
<p><a href="http://people.oregonstate.edu/~benoitbk/reprints/Benoit-Bird%20Animation%203.wmv">3-d view</a>: Dolphin positions recorded from a multibeam sonar observation of a  foraging dolphin group. This animation is a composite of three  observations overlapping in foraging stage to permit a visualization of a  complete foraging bout. Each frame is the composite of six successive  sonar echoes, providing higher resolution and three- dimensional  information while minimizing noise in the data. The strong air cavity  echo from each dolphin is represented by the dots. The travel of the  vessel has been removed and the data is shown at 8 times real time.</p>
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		<title>Genius of the Sea</title>
		<link>http://oregonstate.edu/terra/2011/02/genius-of-the-sea/</link>
		<comments>http://oregonstate.edu/terra/2011/02/genius-of-the-sea/#comments</comments>
		<pubDate>Tue, 01 Feb 2011 04:57:22 +0000</pubDate>
		<dc:creator>Lee Sherman</dc:creator>
				<category><![CDATA[Departments]]></category>
		<category><![CDATA[Earth]]></category>
		<category><![CDATA[Healthy Planet]]></category>
		<category><![CDATA[Winter 2011]]></category>
		<category><![CDATA[acoustics]]></category>
		<category><![CDATA[Ecology]]></category>
		<category><![CDATA[Kelly Benoit-Bird]]></category>
		<category><![CDATA[Marine Science & the Coast]]></category>
		<category><![CDATA[Oceanic and Atmospheric Sciences]]></category>

		<guid isPermaLink="false">http://oregonstate.edu/terra/?p=6729</guid>
		<description><![CDATA[Kelly Benoit-Bird studies ocean organisms smaller than a microchip and bigger than a luxury motor home — the tiniest crustaceans to the mightiest cetaceans. In effect, she studies just about anything that swims or drifts in the sea: copepods and krill, diatoms and dinoflagellates, siphonophores and salps, spinner dolphins and Humboldt squid, Pacific sardines and [...]]]></description>
				<content:encoded><![CDATA[<div id="attachment_6640" class="wp-caption alignleft" style="width: 210px"><a href="http://oregonstate.edu/terra/wp-content/uploads/2011/01/kelly_benoit_bird.jpg"><img class="size-medium wp-image-6640" title="kelly_benoit_bird" src="http://oregonstate.edu/terra/wp-content/uploads/2011/01/kelly_benoit_bird-200x300.jpg" alt="" width="200" height="300" /></a><p class="wp-caption-text">Kelly Benoit-Bird (Photo: Craig Mitchelldyer, Getty Images for the McArthur Foundation)</p></div>
<p>Kelly Benoit-Bird studies ocean organisms smaller than a microchip and bigger than a luxury motor home — the tiniest crustaceans to the mightiest cetaceans. In effect, she studies just about anything that swims or drifts in the sea: copepods and krill, diatoms and dinoflagellates, siphonophores and salps, spinner dolphins and Humboldt squid, Pacific sardines and sperm whales. Not only is she unbounded by species classifications, she also is unrestrained by the dimensions of time and space. What drives her research is, indeed, the traversing of those very dimensions by animals and plants in search of survival.</p>
<div class="side-right">
<h3><a href="http://oregonstate.edu/terra/2011/02/dolphins-hunt-together/">Dolphins Hunt Together</a></h3>
<p>Watch dolphins corral their quarry and work together to feed in these animations. <a href="http://oregonstate.edu/terra/2011/02/dolphins-hunt-together/">Read more.</a></p>
</div>
<p>As a pelagic (open-ocean) ecologist, Benoit-Bird investigates the intricate interactions among predators and prey that take place day and night, full moon to new moon, summer to winter, El Niño to La Niña in Earth’s vast oceans.</p>
<p>“Despite the apparent variety of the ongoing research projects in my lab, all of our research aims to understand the role of spatial and temporal patterns in ecological processes on spatial scales ranging from sub-meter to hundreds of kilometers, at temporal scales of minutes to years, and over a range of animal size from zooplankton to great whales,” Benoit-Bird explains on her webpage for Oregon State University’s College of Oceanic and Atmospheric Sciences.</p>
<p>The challenge is almost beyond imagining. Within the world’s 326 million cubic miles of seawater, most species interactions happen where humans cannot witness them. Besides, as Benoit-Bird points out, the marine environment is in constant motion. On land, plants hold fast to the ground. Forests may be complex ecosystems to study, but at least they stay put. At sea, plants drift on tides and currents, rising and falling in the water column with the sun and the moon and the seasons.</p>
<p>“In the ocean, plants are incredibly small, have very little structure and move all over the place — sometimes even actively,” the researcher says. “Some of the plants can swim.”</p>
<p>To compensate, Benoit-Bird extends her senses. She devises novel acoustic and optical technologies that collect data remotely, giving scientists a virtual front-row seat on some of nature’s most mysterious processes. Her innovations are opening the world’s oceans to human understanding in ways never before possible. In 2010, the John D. and Catherine T. MacArthur Foundation recognized her pioneering work with a prestigious $500,000 MacArthur Fellowship — popularly known as a “Genius Award.”</p>
<h3><span style="font-weight: normal;">Life in Layers</span></h3>
<p>Instead of being like a big pot of soup with its ingredients evenly mixed, the ocean is more like a big blue torte with dense congregations of organisms layered vertically, Benoit-Bird and other oceanographers have learned in recent years. In coastal waters across the planet, scientists have discovered that plankton, both in its plant and animal forms, coalesce into layers two or three feet thick, sometimes extending for miles horizontally. These “thin layers” of tiny life forms — which Benoit-Bird calls “great smorgasbords of food”<br />
— likely hold critical clues to how ocean ecosystems work.</p>
<p>“While thin layers are just beginning to be investigated,” Benoit- Bird writes in a recent issue of <em>Continental Shelf Research</em>, “thin layers are likely to be important for a variety of biological processes, including growth rates, reproductive success, grazing, predator-prey encounters, nutrient uptake and cycling rates, as well as toxin production.”</p>
<p>To get inside those mysteries from the deck of a research vessel, Benoit- Bird has been developing a whole new generation of tools. She uses sonar technologies to collect acoustical data that are then fed into computers for analysis. To broaden their options, she and her collaborators have experimented with linking disparate gear types, such as video cameras and echosounders (devices that locate layers and schools of organisms by sending out pulses of sound waves). They’ve designed new uses for old standbys, like retrofitting a remotely operated vehicle (“a little tethered robot”) to find and track plankton layers by following water density. They’ve invented a new kind of sonar to study the distribution of individual zooplankton inside thin layers.</p>
<p>Her ambitious research goals, supported by the National Science Foundation and other agencies, necessarily push her toward more expansive technologies.</p>
<p>“My perspective is that we shouldn’t be limited by the tools we have,” she says. “I like to think about the question first and figure out how to address it later. It may mean we have to develop a new tool or a new way of analyzing data or a new way of deploying instruments to get at the questions we’re interested in.”</p>
<h3><span style="font-weight: normal;">A &#8220;Spatial Ballet&#8221;</span></h3>
<p>Computer animations created from recent acoustical studies show fish diving through plankton layers, gobbling holes in the tightly packed, food-rich patches. Another animation shows spinner dolphins swimming in tight formation to corral layers of lanternfish during coopera- tive feeding.</p>
<p>“The emerging picture is one of an incalculably complex, finely tuned, and delicate interaction between predators and prey, chemistry and light, currents and water column, night and day,” writes author Julia Whitty in a recent <em>Mother Jones</em> article featuring Benoit-Bird. “Some semblance of this spatial ballet, played in weightless three-dimensional darkness, has likely been part of the oceans since the oceans were brought to life: layers of life gathering in extremely high densities to feed or to avoid being eaten.”</p>
<p>_____________________________</p>
<p>For information about supporting research and teaching through faculty  endowments, contact the Oregon State University Foundation,  1-800-354-7281 or visit <a href="http://campaignforosu.org/">CampaignforOSU.org</a>.</p>
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		<title>Out of the Depths</title>
		<link>http://oregonstate.edu/terra/2008/06/out-of-the-depths/</link>
		<comments>http://oregonstate.edu/terra/2008/06/out-of-the-depths/#comments</comments>
		<pubDate>Mon, 30 Jun 2008 18:50:15 +0000</pubDate>
		<dc:creator>Mark Floyd</dc:creator>
				<category><![CDATA[Features]]></category>
		<category><![CDATA[Healthy Planet]]></category>
		<category><![CDATA[Summer 2008]]></category>
		<category><![CDATA[acoustics]]></category>
		<category><![CDATA[Marine Science]]></category>
		<category><![CDATA[Oceanic and Atmospheric Sciences]]></category>
		<category><![CDATA[squid]]></category>

		<guid isPermaLink="false">http://oregonstate.edu/dept/terra/?p=5592</guid>
		<description><![CDATA[It was like a scene from a grade-B horror film. On a gently rocking vessel in the warm waters of the Sea of Cortez, a young oceanographer earnestly watches her computer screen while colleagues lower a cable into the water.]]></description>
				<content:encoded><![CDATA[<p><a href="http://oregonstate.edu/dept/terra/wp-content/uploads/2010/09/101U8617.tif"></a></p>
<div id="attachment_5598" class="wp-caption alignleft" style="width: 310px"><a href="http://oregonstate.edu/dept/terra/wp-content/uploads/2010/09/101U8620.crop_.jpg"><img class="size-medium wp-image-5598" title="101U8620.crop" src="http://oregonstate.edu/dept/terra/wp-content/uploads/2010/09/101U8620.crop_-300x135.jpg" alt="" width="300" height="135" /></a><p class="wp-caption-text">Kelly Benoit-Bird was recognized in 2010 with a MacArthur &quot;genius&quot; award for her groundbreaking work in ocean ecology.</p></div>
<p>It was like a scene from a grade-B  horror film. On a gently rocking vessel in the warm waters of the Sea of  Cortez, a young oceanographer earnestly watches her computer screen  while colleagues lower a cable into the water.</p>
<p>Instruments aboard the ship, the Pacific Storm, ping sound waves  toward the cable. The oceanographer’s eyes flicker across the screen to  make sure the signal is clear. Tethered to the cable is a 5-pound  Humboldt squid, and the sound waves, set at 38 kilohertz, bounce off the  squid. An image shows up on the screen.</p>
<p>The oceanographer raises her fist in triumph. It marks the first time  scientists had clearly picked up a strong sonar signal for squid, which  lack the bones and swim bladders that give away other marine creatures.</p>
<p>Suddenly a second image appears, darting up from below. The acoustic  signal tracks it from the depths toward the cable — and the tethered  squid. It is another squid, larger than the first, and it attacks the  tethered animal. The oceanographer screams.</p>
<p>Fade to black.</p>
<div>
<h3>Seeing with Sound</h3>
<p>“Actually, I think I swore instead of screamed,” says Kelly  Benoit-Bird cheerfully. “We were watching it in ‘real time,’ and it was  like a scene from a scary movie. But in this case, the science is real.”</p>
<p>In April, Benoit-Bird, an assistant professor in Oregon State  University’s College of Oceanic and Atmospheric Sciences, published a  paper in the journal Acoustical Society of America on her success, and  she received 19 e-mails from colleagues the first day the article  appeared. “I’ve never had such a response before,” she says.</p>
<p>Co-authors included William Gilly of Stanford University’s Hopkins  Marine Station, Whitlow W. L. Au of the University of Hawaii and Bruce  Mate of OSU’s Marine Mammal Institute. Support for the work came from  the Marine Mammal Endowment at OSU and from a National Science  Foundation grant to Gilly.</p>
<p>The reasons for the excitement are two-fold. On one hand, the ability  to track squid with sonar may reveal new details about how ocean  ecosystems work. Squid are thought to be a primary food source for sperm  whales, but ecologists have never been sure how the whales hunt. A  study just five years ago concluded that whales couldn’t use  echolocation to target squid because signals wouldn’t reflect off the  squids’ soft bodies. Now researchers will need to re-examine the  capacity of whales, dolphins, porpoises and other marine creatures to  use their own sonar.</p>
<p>Benoit-Bird’s research is also important, however, because it gives  scientists a new way to look at an important link in the marine food  chain. Squid may not have been properly appreciated, but their impact is  becoming apparent. The Humboldt squid appears to be expanding its  territory, moving from the Pacific Ocean off Mexico and California into  the colder waters near Oregon.</p>
<p>And that is causing some concern.</p>
<p>“The Humboldt squid is a voracious predator that will eat anything it  can get its tentacles on,” Benoit-Bird says. “We put a pair of 10-pound  squid into a tank and one immediately beheaded the other. These are  fierce little beasts.”</p>
<p>Mexican fishermen have a name for the Humboldt squid: diablos rojos,  or red devils. Known for their strength and razor-sharp beaks, these  animals flash red and white at the end of a fishing line. They can get  as large as six feet in length and weigh up to 100 pounds, though adults  more typically weigh 20 to 40 pounds. They travel in schools of up to  1,000 squid and will eat any fish in sight.</p>
<p>In the Sea of Cortez, the Humboldt squid target lanternfish but are  opportunistic feeders. They are highly energetic and require a lot of  food to maintain their metabolic rate. Their move into northern  California, Oregon and Washington — at a time when salmon stocks are  depressed — is a concern to scientists like Benoit-Bird, who studies  ecological interactions among marine species.</p>
<p>“Typically, when a species moves into a new area, it adapts,” she  said. “If they can’t find the lanternfish they ate in the Sea of Cortez,  they may look at juvenile salmon, as well as herring, sardines and  other species that salmon may eat.</p>
<p>“Then there is the flip side of the equation,” Benoit-Bird points  out. “What will target the Humboldt squid as prey? In Mexico, it is the  sperm whale, but they are uncommon off Oregon. Most of our whales are  baleen whales, and these squid will be too big for them. Perhaps orcas,  perhaps sharks…or they may have free rein.”</p>
<p>Next to sperm whales, the primary predators for the Humboldt squid in  Mexico are coastal villagers who row their wooden boats offshore at  night, when the red devils are closer to the surface. Fishermen catch  squid by the hundreds and sell them for food. It doesn’t appear that  over-fishing is a problem. National Geographic recently reported that  some 10 million squid might be living in a 25-square-mile area off the  city of Santa Rosalia.</p>
<p>Reliable estimates have been hard to achieve and are historically  based on catch rates. With the new acoustic advancement made by  Benoit-Bird and colleagues, scientists now have a tool to better monitor  the squids’ range and habits.</p>
<h3>Density Matters</h3>
<p>Scientific advancements are rarely easy, and this one was no  exception. In 2006, Bruce Mate, director of OSU’s Marine Mammal  Institute, was taking the Pacific Storm to the Sea of Cortez to study  sperm whales and invited Benoit-Bird along to look at its prey, the  Humboldt squid. She assembled funding from a variety of sources to pay  for the necessary technicians and instruments.</p>
<p>The Pacific Storm is a former fishing vessel, donated to OSU for use  by the Marine Mammal Institute and retrofitted for research. Once they  were in the Sea of Cortez, Benoit-Bird and her colleagues had to catch  squid and dissect them, carefully measuring each body part and  experimenting with different sound frequencies to see what signals might  work.</p>
<p>“You need a density difference to get back scatter,” Benoit-Bird  says, “and squid are difficult because they have no hard parts.  Eventually, we used multiple frequencies and were able to pick up a  clear signal, probably from the brain case, but perhaps from the teeth  on the suckers along their arms.”</p>
<p>Through days of experiments, the researchers were able to calibrate  the signal to pinpoint individual squid and even estimate their size.  They were able to observe a squid group, how individuals moved in the  water and when they rose from the depths to feed. Using this technology,  Benoit-Bird says, scientists should be able to transect a fishing  ground and get a better estimate of the squid population.</p>
<p>She also hopes to go back through 20 years of hake surveys from the  National Marine Fishery Services and recalibrate their acoustic signal  to look for evidence of squid.</p>
<p>“We don’t know why Humboldt squid are moving north up the coast,”  Benoit-Bird adds, “but now we have a better chance of studying their  movements and impact on the environment.”</p>
<p><strong>Editor’s note:</strong>This story also appears on <a href="http://www.livescience.com/">LiveScience.com</a> <em>Behind the Scenes</em> in collaboration with the National Science Foundation. See more about <a href="http://oregonstate.edu/%7Ebenoitbk/">Kelly Benoit-Bird’s research</a>.</p>
<div id="development_links"><a name="links"></a></p>
<ul>
<li><a title="Opens in a new window." href="http://www.coas.oregonstate.edu/index.cfm?fuseaction=content.search&amp;searchtype=people&amp;detail=1&amp;id=607" target="_blank">Kelly Benoit-Bird’s Web page</a></li>
<li><a title="Opens in a new window." href="http://www.coas.oregonstate.edu/" target="_blank">College of Oceanic and Atmospheric Sciences</a></li>
<li><a title="Opens in a new window." href="http://mmi.oregonstate.edu/" target="_blank">OSU Marine Mammal Institute</a></li>
<li><a title="Opens in a new window." href="http://campaignforosu.org/" target="_blank">The Campaign for OSU</a></li>
<li><a title="Opens in a new window." href="http://www.nsf.gov/" target="_blank">National Science Foundation</a></li>
<li><a title="Opens in a new window." href="http://www.onr.navy.mil/" target="_blank">Office of Naval Research</a></li>
<li><a title="Opens in a new window." href="http://www.noaa.gov/" target="_blank">National Oceanic and Atmospheric Administration</a></li>
</ul>
<p>OSU news release</p>
<ul>
<li><a title="Opens in a new window." href="http://oregonstate.edu/dept/ncs/newsarch/2006/Jul06/benoitbird.html" target="_blank">OSU Oceanographer Receives White House ‘Early Career’ Award</a> (7-28-06)</li>
<li><a title="Opens in a new window." href="http://oregonstate.edu/dept/ncs/newsarch/2005/Jun05/investigator.htm" target="_blank">COAS Professor Receives Young Investigator Award</a> (6-21-05)</li>
</ul>
</div>
</div>
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