Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study finds southern Indian Ocean humpbacks singing different tunes

02.02.2012
Researchers from WCS, Columbia University, and others find an unusual divide in song themes sung by whales in Madagascar and western Australia

A recently published study by the Wildlife Conservation Society and others reveals that humpback whales on both sides of the southern Indian Ocean are singing different tunes, unusual since humpbacks in the same ocean basin usually all sing very similar songs.

The results of the study—conducted by researchers from WCS, Columbia University, and Australia —contradict previous humpback whale song comparisons. Generally, when song from populations in the same ocean basins are compared, researchers find that the songs contain similar parts or "themes." The differences in song between the Indian Ocean humpback populations most likely indicate a limited exchange between the two regions and may shed new light on how whale culture spreads.

The paper appears in the January edition of Marine Mammal Science and is available on the journal's website. The authors of the study include: Anita Murray, formerly of the Wildlife Conservation Society and Columbia University ; Salvatore Cerchio, Yvette Razafindrakoto, and Howard Rosenbaum of the Wildlife Conservation Society; Robert McCauley of Curtin University, Perth, Australia; Curt S. Jenner of the Centre for Whale Research, Fremantle, Australia; Douglas Coughran of the Department of Environment and Conservation, Perth, Australia; and Shannon McKay of the School of Life and Environmental Science, Warrnambool, Australia.

"In the Northern Hemisphere, within an ocean basin whales sing songs that are composed of the same themes. However, whales in the southern Indian Ocean are singing almost completely different songs. Songs from Madagascar and Western Australia only shared one similar theme, the rest of the themes were completely different," said lead author Anita Murray, who conducted the research while a graduate student at Columbia University and the Wildlife Conservation Society and is currently pursuing her doctorate at the University of Queensland in Australia. "The reason for this anomaly remains a mystery. It could be the influence of singing whales from other ocean basins, such as the South Pacific or Atlantic, indicating an exchange of individuals between oceans which is unique to the Southern Hemisphere."

The songs of humpback whales are generally sung by male individuals on a population's winter breeding grounds, migratory routes, and summer feeding grounds. The songs themselves are complex arrangements of parts or "themes," consisting of ascending and descending wails, moans, and shrieks that are repeated in cycles lasting up to 30 minutes. The transmission of songs between individuals from different populations is likely to occur on feeding grounds or during migration when whales from different populations mix. Or, transmission of song may occur when individual male "troubadours" travel to different breeding grounds between breeding seasons or possibly during the same breeding season.

The research team made recordings of humpback whale songs in two locations in coastal Madagascar and three locations along Western Australia during the 2006 breeding season. Research teams in both regions used hydrophones to record the songs of 19 individual whales. Overall, the authors captured more than 20 hours of whole and partial songs for visual and audio analysis. The comparison revealed few similarities between songs; of the eleven themes recorded in both regions, only one theme was shared by both populations.

Due to the limited duration of the study (only one breeding season), researchers point out that continued analysis of songs in Madagascar and Australia are needed to examine the reasons for the limited similarity in repertoire.

Dr. Howard Rosenbaum, Director of WCS's Ocean Giants Program said: "These song comparisons complement our findings based on other methods, such as those from genetic analysis, to understand how whale populations interact with one another."

WCS conservationist Salvatore Cerchio added: "We have glimpsed here a snapshot of differences in repertoire between humpback whale populations of the Indian Ocean during a single season. Continued monitoring of these songs can provide us with valuable information on how whale songs are exchanged and how those channels of cultural transmission can be protected in the future."

WCS has been involved in research on humpback whales since the 1960s, when researchers from the New York Zoological Society (now the Wildlife Conservation Society) discovered that the vocalizations of humpback whales are, in fact, songs, defined as a series of themes that are repeated in cycles. For the past decade, WCS's Ocean Giants Program has conducted an extensive molecular analysis of humpback whale populations in the southern Atlantic and Indian oceans in an attempt to better define discrete populations.

The humpback whale is a baleen whale that grows up to approximately 50 feet in length. The species has distinctively long pectoral fins and a head with knobs on the top and lower jaw. The slow-swimming species was hunted commercially until the International Whaling Commission protected the species globally in 1966. Current estimates for humpback whale numbers are widely debated. While they are recovering, total population sizes may represent only a small percentage of the original global population.

John Delaney | EurekAlert!
Further information:
http://www.wcs.org

More articles from Studies and Analyses:

nachricht New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

nachricht Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>