The analysis of dolphin sounds has been developed to classify the various sounds to finally know more about the dolphin communication abilities Three classes of sounds appear in dolphins: 1. Whistles, 2. Burst pulse sounds and 3. Sonar clicks
Whistles and burst pulse sounds are obviously used as communication sounds resp. language. The clicks are broadband emmissions for echolocating. The 'signature whistle theory' is being discussed worldwide and in various research projects the scientist come to the conclusion, that there is evidence for the existance of signature whistles, used as a name-like personal identification code.
This is a spectrogram of a whistle triplet produced by a free-ranging Globicephala mac. Triplets of this whistle contour are often produced by many dolphin species. I heard it from Tursiops t., Stenella frontalis, Stenella coe., Globicephala mac. and Delphinus delphis.
The frequency analysis taken at t= 0.55 s shows three peaks at approx. 5 kHz, 10 kHz and 12 kHz.
This burst pulse sound was produced by a free-ranging Globicephala mac. Duration=0.7s
The following waveform picture shows the
highlighted segment
(316ms - 344ms) from the waveform above.
This single pulse starts at 326.6ms and ends at 330.3ms. Duration=3.7ms
The spectrogram shows various harmonics.
A frequency analysis was
taken at t=326ms.
Peaks of the harmonics at approx. 3, 5,
7, 9, 11, 13.7,
15.5 and 17 kHz.
Technical devices: B&K Hydrophone, Aiwa DAT Recorder 48 kHz
Software used: Sounddesigner II, CoolEdit, SpectraPlus, PaintShopPro