[MARMAM] New Paper on Australian Sea Lion
isabelle.charrier at ibaic.u-psud.fr
Wed Nov 29 03:32:09 PST 2006
The following paper has been recently published in Journal of Mammalogy.
Charrier, I & Harcourt, R.G. 2006. Individual vocal identity in mother and
pup Australian sea lions (Neophoca cinerea). J. Mammal. 87(5), 929-939.
Individual vocal recognition between mothers and pups has been widely
observed in pinnipeds, especially
otariids. Otariids are colonial breeders; mothers suckle only their own
offspring, aggressively attacking
nonrelated young. Mothers alternate foraging trips with periods ashore, and
at each return to the colony, mothers
and pups must find each other among all the individuals of the colony. In
the Australian sea lion (Neophoca
cinerea), the need for a finely tuned mechanism of recognition is
exacerbated by their habit of changing the
nursing location over the course of lactation. We investigated potential
acoustic parameters used in motherpup
recognition in Australian sea lions. We measured 11 acoustic parameters on
calls of mothers and pups and found
that several parameters (fundamental frequency, energy spectrum, amplitude,
and frequency modulation) were
highly individually specific. Discriminant analysis correctly assigned
calls to individual mothers or pups with an
average classification rate of 65% and 77%, respectively. Spectral features
and frequency modulation were the
most important features distinguishing individuals. Lastly, principal
component analysis showed that calls of
pups and mothers were easily distinguishable using energy spectrum and
frequency modulation. Comparison
with other pinniped species suggests that individual vocal identity is
likely to be selected through ecological
constraints such as density of the colony, degree of polygyny, likelihood
of allosuckling or fostering, and degree
of maternal absence during lactation.
A pdf file is available and can be sent on request
(isabelle.charrier at ibaic.u-psud.fr)
All the best,
Équipe Communications Acoustiques.
NAMC-CNRS UMR 8620,
Université Paris Sud, Bat.446
F-91405, Orsay, FRANCE.
Email: isabelle.charrier at ibaic.u-psud.fr
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the MARMAM