Not to rehash Treble's old thread but last night while fishing the Sound in the multitude of bunker schools my son and I heard "the sound", "the bloop" or whatever it is you want to call it. The only difference is that this time we witnessed its effects on the fish. Every single fish in every bunker school near us would splash when that sound occured. Happened 3 times. Definitely coming from the water and can only imagine it sends a shock waver through the water. My son was curious and seems there are a lot of hits/info on the web. Check out www.bloopwatch.org there are many links to CNN articles and other interesting info. I would still like to get a definitive answer as to what the heck it is that we are hearing.