[MARMAM] New paper: Individuality embedded in the isolation calls of captive beluga whales (Delphinapterus leucas)

thank_you_for_email_5yuka at yahoo.co.jp thank_you_for_email_5yuka at yahoo.co.jp
Fri Oct 9 01:24:59 PDT 2015

Dear  all

I'm pleased to announce the following paper.

Title: Individuality embedded in the isolation calls of captive beluga whales (Delphinapterus leucas)

Authors: Mishima Y., Morisaka T., Itoh M., Matsuo I., Sakaguchi A., Miyamoto Y.

Zoological letters 2015 1:27
DOI: 10.1186/s40851-015-0028-x

 Species with fission-fusion social systems tend to exchange individualized contact calls to maintain group
cohesion. Signature whistles by bottlenose dolphins are unique compared to the contact calls of other non-human
animals in that they include identity information independent of voice cues. Further, dolphins copy the signatures of
conspecifics and use them to label specific individuals. Increasing our knowledge of the contact calls of other cetaceans
that have a fluid social structure may thus help us better understand the evolutionary and adaptive significance of all
forms of individually distinctive calls. It was recently reported that one type of broadband pulsed sounds (PS1), rather
than whistles, may function as individualized contact calls in captive belugas. The objective of this study was to assess
the function and individual distinctiveness of PS1 calls in an isolation context. Recordings were made from five captive
belugas, including both sexes and various ages.

 PS1 was the predominant call type (38 % in total) out of five broader sound categories. One sub-adult and three
adults had individually distinctive and stereotyped pulse repetition pattern in PS1; one calf showed no clear stereotyped
pulse repetition pattern. While visual inspection of the PS1 power spectra uncovered no apparent individual specificity,
statistical analyses revealed that both temporal and spectral parameters had inter-individual differences and that there
was greater inter-individual than intra-individual variability. Discriminant function analysis based on five temporal and
spectral parameters classified PS1 calls into individuals with an overall correct classification rate of 80.5 %, and the most
informative parameter was the average Inter-pulse interval, followed by peak frequency.

 These results suggest that belugas use individually distinctive contact calls in an isolation context. If belugas
encode signature information in PS1 calls, as seen in bottlenose dolphins, the pulse repetition pattern may be the carrier,
as it is individually stereotyped and appears to require vocal development. This idea is supported by the finding that the
average inter-pulse interval is the most powerful discriminator in discriminant analysis. Playback experiments will elucidate
which parameters are perceived as individual characteristics, and whether one of the parameters functions as a signature.

This is an open-access.
If you are interested in this paper, please read it.
Download site: http://zoologicalletters.biomedcentral.com/articles/10.1186/s40851-015-0028-x


Yuka Mishima

Yuka Mishima
The Graduate School of Marine Science and Technology
Tokyo University of Marine Science and Technology
email: yuka.mishima.0614 at gmail.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.uvic.ca/pipermail/marmam/attachments/20151009/5ce01ff7/attachment.html>

More information about the MARMAM mailing list