Every dolphin has it’s own unique ‘signature whistle‘. Listening to these whistles is one way to identify specific dolphins and track their whereabouts.
Here’s an extract from an article that appeared recently in ‘Ear on the SEA’ E-
“Bottlenose dolphins ( Tursiops truncatus ) have elaborate sound production and receiving systems. In the Tursiops, four major types of vocalisations have been identified: whistles, clicks, burst pulsed sounds and chirps.”
“Whistles are used in communication. They are continuos, narrow-
“Clicks are directional and used for echolocation. These are short, broad-
“Burst pulsed sounds occur commonly in social and emotional context and are thought to be used for communication. These are trains of clicks with repetition rates of up to 5000 clicks per second. The high repetition rate gives a tonal quality to the sounds.
“Chirps are thought to be used in communication. These sounds are pulsed, frequency-
All of the communications related sounds are well within the human hearing range. Even the echolocation clicks can have audible components within the nominal 20kHz upper limit of human hearing –
Dolphin whistles were observed with both upward and downward sweeps. An up-
The study was based on a 63 minute tape made at Parc Asterix in France in 1996. The ‘subjects’ were 5 adult dolphins and one calf. The researchers did not see the dolphins nor were they able to correlate the animals actions with the sounds they produced. But, it gives us a good base to understand the kind of vocalisations we will hear in the wild.
This research project is also an excellent example of the quality of work that can be produced from a ‘single encounter’ using readily available tools. DolphinEar and the software included in the package can get you started in your own research. Casual encounters with dolphins lasting 20-