Bad news for whales and dolphins: Navy to expand sonar testing

[adirondacker]

10. They're not fishfinders or typical single/multibeam systems.As hack89 pointed out, they are used to

detect subs. In order to do this in Vast areas of ocean, they will "light up" the region with an extremely loud and variant frequency of acoustics to garner an image used to locate underwater anomalies. I was on a cruise that performed this and I can attest that the acoustics are strong enough to shake and vibrate the hull of any nearby ship. Enough so, that it would rattle belongings off of a shelf if not secured, and annoying enough to keep you up all night even when completely exhausted.