Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Secrets of whales’ long-distance songs are being unveiled

21.02.2005


Navy’sundersea microphones -- but sound pollution threatens



Why do whales in the North Atlantic Ocean seem to be moving together and coherently? What is impelling them forward. How do they communicate with each other, seemingly over thousands of miles of ocean? And how can this acoustical habitat be protected?

For nearly nine years Cornell University researcher Christopher Clark -- together with former U.S. Navy acoustics experts Chuck Gagnon and Paula Loveday -- has been trying to answer these questions by listening to whale songs and calls in the North Atlantic using the navy’s antisubmarine listening system. Instead of being used to track Soviet subs as they move through the Atlantic, the underwater microphones of the Sound Surveillance System (SOSUS) can track singing blue, fin, humpback and minke whales.


From the acoustical maps he and his colleagues have obtained, Clark has come to realize that he has been thinking about whales at the wrong time scale. "There is a time delay in the water, and the response times for their communication are not the same as ours. Suddenly you realize that their behavior is defined not by my scale, or any other whale researcher’s scale, but by a whale’s sense of scale -- ocean-basin sized," he says.

Clark, the I.P. Johnson Director of the Bioacoustics Research Program at Cornell in Ithaca, N.Y., will discuss his research into the rich acoustical environment of whales at a news briefing during the annual meeting of the American Association for the Advancement of Science (AAAS) Feb. 19 at 3 p.m. in Salon B, mezzanine level, Marriott Wardman Park hotel, Washington, D.C. He also will describe his research in an AAAS seminar Feb. 20 at 8:30 a.m., lobby level, Virginia Suite A, Marriott Wardman Park.

"We know very little about whale communications. That is why we are looking for patterns of association and coordination. The problem is that the whales are spaced so far apart," says Clark. However, the SOSUS system is providing a wealth of new data. In weeklong soundings at the U.S. Navy’s Joint Maritime Facility in St. Mawgan, Cornwall, England, Clark has obtained thousands of acoustical tracks of singing whales for the different species throughout the year. "We now have the ability to fully evaluate where they are and how long they sing for," he says. "We now have evidence that they are communicating with each other over thousands of miles of ocean. Singing is part of their social system and community."

Using SOSUS, Clark can move a cursor around a screen and listen in on different areas of the North Atlantic. If he hears a whale singing, he can fix its location and position it in space and time and observe animals that are many tens of miles apart -- cohorts of humpback singers moving coherently -- and watch the collective migration of species in large portions of the ocean basin. "So if I am a whale off Newfoundland, I can hear a whale off Bermuda," says Clark.

"Whales will aim directly at a seamount that is 300 miles away, then once they reach it, change course and head to a new feature. It is as if they are slaloming from one geographic feature to the next. They must have acoustic memories analogous to our visual memories," he says.

Among the puzzling questions yet to be answered is exactly what motivates much of whales’ long-distance movements. Watching the positions of fin whale singers, males whose songs are highly repetitious and hierarchically organized, Clark sees on his screen a random collection of dots that seem to be moving together coherently through the ocean. "This is not migration. So what is influencing their movement and distribution? Ocean features associated with resources? If so, what are the features they are cuing in on?" Clark asks.

He notes the irony that just as researchers are gaining new ways of understanding the linkages between whales and oceanographic features, what he is hearing is the rising tide of noise from an increasingly urbanizing marine environment, the collective noises from shipping traffic, oil and gas exploration and production, and recreational traffic. And every decade the amount of noise is doubling.

"Many whales have very traditional feeding grounds and their migratory routes occur along shallow coastlines which are now some of the noisiest, most heavily impacted habitats," Clark explains. But often it is along these routes that the male songs are sent long distance to prospective females, who might not receive the message through the "ocean smog."

Says Clark, "If females can no longer hear the singing males through the smog, they lose breeding opportunities and choices. The ocean area over which a whale can communicate and listen today has shriveled down to a small fraction of what it was less than a century ago."

David Brand | EurekAlert!
Further information:
http://birds.cornell.edu/brp/
http://www.cornell.edu

More articles from Life Sciences:

nachricht Researchers identify potentially druggable mutant p53 proteins that promote cancer growth
09.12.2016 | Cold Spring Harbor Laboratory

nachricht Plant-based substance boosts eyelash growth
09.12.2016 | Fraunhofer-Institut für Angewandte Polymerforschung IAP

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>