Underwater Sonar

[AL Sanders]

[ame=http://vimeo.com/26395890]Underwater Sonar on Vimeo[/ame]

Unusual sonar sound heard whilst spearfishing. It has been edited to illustrate sounds in close succession, in reality they were at approximately 1 minute intervals. My thoughts are that its a sub as it sounds too structured to be organic? There is also a faint engine sound in the background although there are numerous tankers moored offshore.
Am keen to hear if anyone has heard similar sounds.

 

[Chris_C_NZ]

I blame the russians, who in turn will blame a school of mackerel...

 

[ReefTroll]

A Nav beacon possibly?

 

[AL Sanders]

A few people have since told me its dolphin communication which would make sense as we filmed a pod a couple of weeks later in the same area.