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 Multi-year study finds 'hotspots' of ammonia over world's major agricultural areas
17.03.2017 | University of Maryland

nachricht Diabetes Drug May Improve Bone Fat-induced Defects of Fracture Healing
17.03.2017 | Deutsches Institut für Ernährungsforschung Potsdam-Rehbrücke

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: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Argon is not the 'dope' for metallic hydrogen

24.03.2017 | Materials Sciences

Astronomers find unexpected, dust-obscured star formation in distant galaxy

24.03.2017 | Physics and Astronomy

Gravitational wave kicks monster black hole out of galactic core

24.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>