Yes. The blind Ganges Dolphin (it truly is blind although the eye can
detect changes in light) puts out the highest voice in the animal
kingdom: up to 356kHz if one can imagine. So, obviously, the vocal
bursts need to be VERY loud to travel any distance because of the
short waveform. It is estimated that in order for the signal to
travel any distance much further than the length of the critter
(usually under 12ft or 350cm) the output level re 1mpa needs to be
somewhere in the range of 225dB.
The dolphin species is critically endangered with fewer and fewer
numbers found with each passing year because of a combination of
events: high levels of pollution in the Ganges and far less run-off
from the Himalayas thus lowering the levels in the river.
Bernie
On Oct 8, 2008, at 3:06 PM, Greg Simmons wrote:
> Does anyone have any information about sounds made by the Gangetic
> Dolphin (Platanista Gangetica)? As I understand it, this endangered
> species has very poor eyesight and navigates mostly by echolocation.
>
> Are its sounds in the range of human hearing? If so, are there any
> recordings I can reference on line?
>
> - Greg Simmons
>
>
>
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