Abstract: Panda's hoots recorded in the present study were characterized by their periodic configuration in the time-domain waveform,frequency and amplitude modulation being not obvious,They were series of quasi-periodic wavs,somewhat different from different panda,but all assuming the shape of a distorted Greek letter "μ" .
In the hoot spectra there usually were 2 distinct frequency bands.For week hoots,the first band was more in tensethan the second.With the increase of the hoot loudness,the second band was strengthened and,in addition,a thirdband appeared.
The hoot signal was quite stable that analysis could the carried on with short samples in 25~100 ms or longer.The fundamefital frequency was 30~240 Hz.