Sound analysis of social calls in chinchillas
J. Bartl1, M. Schneider1, H.U. Kleindienst2 and M. Erhard1
1Institute of Animal Welfare, Ethology, and
Animal Hygiene, Ludwig-Maximilians-University, Munich, Germany
2Max-Planck-Institute for Ornithology, Seewiesen, Germany
Chinchillas are sociable rodents living in families. It is well known
that chinchillas have a hearing range very close to that of humans (125
Hz-16 kHz) and have many different kinds of vocalizations at their disposal.
The aim of this study was to get a survey of vocal behavior of chinchillas
living in sociable groups. During one year twenty chinchillas, housed
in aviaries in 8 groups of 2 to 6, have been investigated.
Vocalizations of the chinchillas were recorded on magnetic tape with
a 4 DS Racal Recorder with frequency response of 100 Hz to 19 kHz. All
vocalizations were digitalized with Avisoft SasLabPro software program
(16 bits, sampling frequency 22050Hz) and spectro- and sonagrams were
made. Syllables were sonographically analyzed and classi.ed according
to parameters like frequency, intensity, duration and number of harmonics.
After that the arrangement of syllables to entire calls was examined.
While chinchillas were active their behavior was directly observed.
At this stage 10 call types, based on different physical structure have
been distinguished and associated with three different functional categories.
Three call types occurred during defensive aggressive interactions between
family members, two during offensive aggressive interactions, and two
further calls during friendly contact between adult chinchillas and one
other call between adults and young. In addition, one call could be associated
with sexual behavior and another one with prevention of raptors (alarm
call).
Because of individual differences in the call variations, the sometimes
smooth transition between some syllables and the variety of combinations
only ten different vocalizations could be connected with a specific context.
Paper presented
at Measuring Behavior 2005
, 5th International Conference on Methods and Techniques
in Behavioral Research, 30 August - 2 September 2005, Wageningen, The
Netherlands.
© 2005 Noldus
Information Technology bv
|