Dear All,
A new paper has been recently published in the Journal of Experimental Biology
on the
pup?s voice recognition by subantarctic fur seal females (Arctocephalus
tropicalis):
Charrier, I., Mathevon, N. and Jouventin, P. ?How does a fur seal mother
recognize the
voice of her pup? An experimental study of Arctocephalus tropicalis.? Journal
of
Experimental Biology, 205, 603-612.
Reprints are now available !
Isabelle Charrier
Abstract :
In the subantarctic fur seal Arctocephalus tropicalis, mothers leave their
pups during
the rearing period to make long and frequent feeding trips to sea. When a
female
returns from the ocean, she has to find her pup among several hundred other.
Taking
into account both spectral and temporal domains, we investigated the
individual vocal
signature occurring in the 'female attraction call' used by pups to attract
their
mother. We calculated the intra- and inter-individual variability for each
measured
acoustic cue to isolate those likely to contain information about individual
identity.
We then tested these cues in playback experiments. Our results show that a
female pays
particular attention to the lower part of the signal spectrum, the fundamental
frequency accompanied by its first two harmonics being sufficient to elicit
reliable
recognition. The spectral energy distribution is also important for the
recognition
process. Of the temporal features, frequency modulation appears to be a key
component
for individual recognition, whereas amplitude modulation is not implicated in
the
identification of the pup?s voice by the mother. We discuss these results with
respect
to the constraints imposed on fur seals by a colonial way of life.
Isabelle Charrier, Ph.D student.
Laboratoire de Biologie Animale
Université Jean Monnet
23 rue Michelon
42023 Saint-Etienne cedex 2
FRANCE
[EMAIL PROTECTED]
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