Blue and beaked whales affected by simulated navy sonar

It revealed what researchers had long suspected, that man-made sound had a negative effect on these deep-diving whales. Beaked whales use sound to hunt as well as to communicate. They produce echolocation clicks as they dive up to 1.5km (1mi) in depth, picking up echoes that bounce off the bodies of the squid they are hunting.


we have know this a long time

[link to www.bbc.co.uk]